testing a chevy oil pump

grumpyvette

Administrator
Staff member
PLEASE READ THE LINKS FIRST




http://www.carcraft.com/techarticles/cc ... ewall.html

http://www.moroso.com/catalog/pdf/Oil_Pumps_106.pdf



http://www.autozone.com/autozone/access ... 67591_0_0_


MEL10551STa.jpg

while helical cut gears will run smoother ,
( ESPECIALLY WITH THE STOCK 7 tooth SBC oil pump)
as you potentially have 2 or three gear teeth in various stages of gear tooth contact
(depends on the angle of tooth engagement)

and yes the design will reduce a tendency to produce a pressure pulse, I have not seen this as a major issue.
simply swapping to the standard volume and pressure BIG BLOCK 12 tooth oil pump in a SBC engine all but eliminates the pulse and pressure and volume issues a sbc oil pump has.


oilvbn2.jpg


sbcvsbbcgearsa.jpg

bbbcpump.jpg

adding "ST" to the end of the existing melling SBC OIL PUMP part number denotes the helical gear set option
a well supported oil pump pick-up tends to cause far fewer issues than one that cab flex and vibrate as metal fatigue can eventually cause them to break
MOR22134.jpg

MOR22147.jpg

BRAZING IS ALWAYS A GOOD IDEA,(just be sure to remove the bye-pass circuite parts and verify function when reinstalled)
148_0506_how_17_z.jpg

vibration can and does occasionally cause pick-up failures,

damage like the pick-up, tube separation, pictured below ,
are common when guys use a flat blade screw driver on the pick-up tube flange. and hammer to seat the oil pump pick-up tube into the oil pump


there are 5/8" and 3/4" tools designed to do the job and they are not that expensive, compared to the cost of a pick-up coming loose on your engine
https://www.summitracing.com/parts/mel-mcat-75
https://www.summitracing.com/parts/mel-mcat-62


broken oilpickup.jpg

there are oil pump testers available commercially or if your mechanically inclined you can fabricate one with reasonable care, after a bit of measuring and purchasing a gauge
http://cvrproducts.com/oil-pressure-test-kit/
oilpumptesterdd.jpg


oilpumptester.jpg


http://www.summitracing.com/parts/mel-77070/overview/
Oil Pump Springs, 70 psi, Steel, Pink, Pins, Chevy, Big Block, Kit

http://www.summitracing.com/parts/mel-7760m/overview/

http://www.summitracing.com/parts/stf-35250/overview/

oilspring.jpg

Many pressure relief springs have one end larger than the other end,the spring always mounts with the larger end facing away from the bypass piston, if installed reversed the piston can,t move far enough to completely open the bypass circuit passage and pressures skyrocket, under some conditions

bbcoilpumpnom.png

BIG-BLOCK-CHEVY-4-BOLT-%20REAR%20MAIN-CAP.jpg

Pump-Stud%20Clearance.JPG

failure to use the correct oil pump,mounting stud, bolt or nut or carefully check clearances when mounting an oil pump can cause problems
pumpss1.jpg

pumpss2.jpg

ONE RATHER COMMON MISTAKE IS USING THE WRONG OIL PUMP STUD OR BOLT TO MOUNT THE OIL PUMP AS IF EITHER EXTENDS THRU THE REAR MAIN CAP IT CAN AND WILL BIND ON THE BEARING AND LOCK OR RESTRICT, SMOOTH ROTATION
to build a tester ID have the oil pump exit bolt to a flat plate epoxied or bolted to the underside of the ammo can lid and have two 1/4" 24 thread bolts that index the oil pump to center on the oil pump exit port from the top side of the ammo can cover and use a threaded stud to clamp the oil pump in place just as its secured to the rear main cap but with a large nut and washer during testing a larger 1/4" NPT centered hole the gauge screws into and then have a spare oil pump drive shaft perfectly lined up with the oil pump drive, ID braze a washer to it about 1/2 way up the shaft and drill the hole thru the ammo can lid and 1/2" thick aluminum reinforcing plate that just allowed the oil pump drive shaft to easily slide thru, and of course the access hole will need to be a oval because ID use the tool to test both 4 and 5 bolt pumps which have the same mount but very slightly different dimensions ,the washer on the drive shaft would prevent the drive shaft from being mis-placed when not in use.
During testing the bye-pass circuit in the oil pump should open, allowing high pressure oil to flow back to the feed or low pressure side of the oil pump, and limit oil increases,in pressure too either about 60-65psi or 65-70psi depending on the resistance of the bye-pass spring selected
the ammo can would hold a few quarts of cheap 10w30 oil to test with and the pump to be tested is simply lowered into the oil as the lids closed and locked in place, the oil can,t go anyplace so the gauge maxes out when the oil pumps relief bye-pass opens telling you almost instantly what the bye-pass pressure is all you need is a drill to spin the oil pump drive a few hundred RPM as oils not compressible and your not feeding any bearing clearances it will fill and max out readily at low rpms


the holes would be very similar to the hole locations circled in green here, with a 4th hole for the drive to the pump
oilpumptesterhole.jpg

Pressure-Gauge-4FLV9.JPG


ammocan.jpg

this is the more common SBC chevy design
ses-3-60-08-002.jpg


this is the more common BBC chevy design
ses-3-90-08-003.jpg

I can easily see where a bit of welder skill and time and use of a drill press, some fabrication time, and you could easily convert a $10 ,50 cal ammo can and a 4" x 10" rectangle of 1/2" thick aluminum plate and a $15 pressure gauge in to a very effective and low cost oil pump test tool, for under $35, similar in concept to this picture below from the video link

http://www.summitracing.com/search?keyword=5556F&dds=1
(chevy small block oil pump bye-pass springs)

http://www.summitracing.com/parts/mel-77060
(chevy big block oil pump bye-pass springs)

oilpumptesterd.jpg


http://www.chevyhiperformance.com/techa ... index.html

http://www.titanspeed.com/content/pump/ ... est01.html

http://www.titanspeed.com/Titan Comparison.pdf




http://www.ehow.com/video_5225928_check ... p-bad.html
"You might find yourself driving one day and notice that your oil pressure light is flickering at you and wonder to yourself, "How do I tell if my oil pump is bad?" Well, it's not always that easy to tell. Generally one of the first things that you ought to do is to check the basics. First off check your oil level; actually you take out the dip stick and make sure that the level is proper. Oil level that is either too low or for that matter too high can cause the oil pressure to be low which could cause the light to come on. The next step would be to determine if there is a problem with whatever turns the light on itself. Most cars use an oil pressure sender or an oil pressure switch and this is a typical oil pressure switch and it's possible that the problem that you're having is only related to a problem with the switch itself. So we really need to find out first off what's the truth. It's possible that the center could be aligned to us. So what we need to do first off is to actually take a wrench and remove the old pressure sender and then with the proper adapters, actually install a manual oil pressure gage and take a reading as to find out what the real oil pressure is. Low gage readings or light being on will normally occur; this, this; an oil, okay, an oil pressure light coming on or a low reading on your dash gage is cause typically with one of these senders senses less than two pounds per square inch. But it can also happen if the internal diaphragm leaks; so that's why we're going to hook up a, an oil pressure gage to find out what their pressure really is. Once the gage is installed, we have to run the engine of full engine operating temperature and see what happens with the pressure at idle and a cruising RPM. So what we'll do is we'll do that and see if the pressure is indeed low. If the pressure still actually shows to be low, we do investigate other things. In order to check the oil pump itself, it maybe necessary to remove the engine oil pan or other components to gain access. Here we have one that's already been removed from a vehicle and I'll remove the plate so we can actually see the popping gears on the inside. The way that the oil is pop is by through the rotation of these gears causing the chambers to expand and then compress in order to cause a popping action of the oil. The test that we do in here are, are two folds. First off we'll do things like measure using a straight edge; the clearance in between the surface and the gears, compare that to specifications and we'll also measure the clearance in between the gears. If either of these things are find to be excessive then the pump must be replaced."

TestFixture_1945.jpg


TestFixtureToPump_1946.jpg


TestFixturePipeThread_1952.jpg


TestSetup_1940.jpg


Id point out up front that oil pressure on the gauge is the result of the resistance the engines clearances cause to oil flow rates,and the viscosity and temperature of the oil.
if your having any problem, maintaining oil pressure you can either increase the flow rate , of viscosity of the oil used or decrease the engines clearances, increasing the oil flow or viscosity is treating a symptom, decreasing the clearances is treating the problem,both approaches will work if done correctly withing reasonable limits and both approaches have points in their favor, and potential problems, IF THE CORRECT PARTS ARE USED, but controlling the oil flow is key to success. a standard z28 sbc oil pump will provide enough oil for most applications
ITS always a good idea to verify the oil pan floor to oil pump pick-up clearance and to braze the pick-up to the oil pump, to reduce the potential for it to come loose.
brazedpick-up1.jpg

yes you can MIG ,TIG or TORCH WELD the pick-up but I found BRAZING works the best and is less likely to warp or crack the pump or pick-up
"how in hell do those twisty, safety wire pliers work?"
wire8.jpg

well a video should be helpful here! Id also point out that you can buy the wire in several diameters and the thicker sizes are far more difficult to use, home depot sells the 22 gauge and 18 gauge, the 22-24 gauge is what youll use far more commonly, as its much easier to use,both stainless (PREFERED) and galvanized are used, and will work on 95% of the applications on a car your likely to use.


MEL10551STa.jpg

while helical cut gears will run smoother ,
( ESPECIALLY WITH THE STOCK 7 tooth SBC oil pump)
as you potentially have 2 or three gear teeth in various stages of gear tooth contact
(depends on the angle of tooth engagement)
and yes the design will reduce a tendency to produce a pressure pulse, I have not seen this as a major issue.
simply swapping to the standard volume and pressure BIG BLOCK 12 tooth oil pump in a SBC engine all but eliminates the pulse and pressure and volume issues a sbc oil pump has.
as a general rule as your engine oil viscosity is reduced the effort required to pump the oil thru clearances is lower and the pressure reading on the gauge drops, thats not necessarily an indication of lower bearing protection, as thats generally a function of oil quality and its formula, and basic components used, in its design, and generally its increased flow rate increases bearing cooling, a good quality 10w30 should ideally provide 20-22 psi at 800rpm idle (anything over 15-17 psi at 800rpm is fine) and 60-65psi by 5000rpm which is all you can use


viscosityvstemperature400.gif

oilvis1.jpg



clearanceload.jpg



clearanceflow.jpg



clearancetemp.jpg


oilmodf.jpg

sbcpumpgearxa.jpg



oilvbn2.jpg

Id also point out that, if you properly set up a performance engine with the proper after market oil control components,the stock engine's oil system, can be vastly improved upon, youll want too, open the oil drain holes and use the proper oil pan, windage screen and crank scraper, its virtually impossible , in a well designed engine to run the engine "long enough to pump all the oil upstairs."
as with a properly designed baffled oil pan, with a carefully fitted and clearanced windage screen and crank scraper, the oil pump simply reaches a flow rate pumping oil out of about 100 or so potential lubricant flow leakage points
Image11a.jpg

SBCOilingnew.png

http://garage.grumpysperformance.com/index.php?threads/whats-a-windage-tray-do.64/
IMAG0741.jpg

IMAG0744.jpg

theres zero doubt an accusump oil feed is a good insurance policy to maintain oil pressure at the bearings, but simply having a 7-8 quart baffled oil pan,properly clearanced, windage screen and crank scraper will insure the oil pressure remains consistent , mostly due to the fact that theres always going to be enough oil over the oil pump pick-up, simply because theres really no room to pack most of the available oil volume in the upper engine ,plus the fact that hot oil flows well.
accumulator7.jpg

LubeV8_W_Scraper02.jpg

OIL PRESSURE read on the oil pressure gauge is a MEASURE of RESISTANCE to oil flow, you can REDUCE the pressure the gauge reads by either increasing the engine clearances or REDUCING the oil viscosity (thickness) so it flows thru the clearances faster with less resistance.(OR INSTALLING A SLIGHTLY WEAKER OIL PUMP BYE_PASS SPRING,that limits the pump pressure before it allows some oil to re-circulate back through the bye-pass valve ,from the high pressure back to the low pressure side of the pump impellers, but only the max pressure you reach is limited by the bye-pass spring,in your oil pressure bye pass circuit and its that spring resistance determines the point where the bye-pass circuit, opens and limits max oil pressure, but the bye-pass circuit has zero to do with anything else, if its functioning correctly,
there are many oil leakage points(100) in a standard Chevy engine.
16 lifter to push rod points
16 push rod to rocker arm points
32 lifter bores 16 x 2 ends
10 main bearing edges
9 cam bearing edges
16 rod bearing edges
2 distributor shaft leaks
1 distributor shaft to shim above the cam gear(some engines that have an oil pressure feed distributor shaft bearing.)
once oil exits the bearings or valve train it flows mostly by gravity back to the oil pan sump, but a properly designed windage screen and crank scraper correctly clearanced allows the spinning crank/rotating assembly to act like a directional pump that drags the vast majority of the oil flow back to the sump, by design.

http://garage.grumpysperformance.com/index.php?threads/whats-a-windage-tray-do.64/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/

sbcvsbbcgearsa.jpg


adding "ST" to the end of the existing melling SBC OIL PUMP part number denotes the helical gear set option
using anti-seize paste on bolt or stud threads helps prevent future problems
antiseize.jpg

using safety wire pliers

ok, If your going to run a big block oil pump,in a 400 sbc, the drive shaft running the oil pump is NOT necessarily shorter, YOULL NEED TO MEASURE ACCURATELY, it depends on the oil pump that's being used, AND THIS VARIES BETWEEN MANUFACTURERS AND OIL PUMP MODELS
but in a 400 block it will need a narrowed waist area to bypass the 400 sbc larger diam. main bearing so the
ARP part # 134-7901 is used, there should be .050 minimum vertical slack/clearance once the oil pump drive shaft and distributor are assembled, obviously best verified with the engine on the engine stand and the oil pan removed with the intake and distributor temporarily assembled. a high capacity baffle oil pan equipped with a windage screen is highly advised, and verifying that the oil pump pick-up is correctly clearanced and brazed into place is mandatory

0704phr_07_z+chevy_big_block_engine+.jpg


notice the welded tabs bracing the oil pump pick-up and that big block pumps have 5 cover screws unlike the small block pump with its 4 screw cover

read these links
sbcoilh5a.jpg


http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.co...l-pumps-pressure-bye-pass-circuit-works.3536/

http://garage.grumpysperformance.com/index.php?threads/installing-an-oil-pump-pick-up-tube.1800/

http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/


http://www.jegs.com/i/ARP/070/134-7901/10002/-1

the milodon 18770 pump is used

http://www.jegs.com/i/Milodon/697/18770/10002/-1

the 3/4" oil pan pick up that fits your oil pan is used

http://www.milodon.com/oil-pans/circle- ... -chevy.asp
409001632_e9c60d11a5.jpg

Chevrolet Performance 14091563
Left (Driver Side) Dipstick Plug
Chevrolet Performance 9421743

Right (Passenger Side) Dipstick Plug
example
#31504 oil pan

LATE MODEL & SPRINT -
COMPETITION SERIES, 7" DEEP
Designed for Dirt or Asphalt racing in Late Models, Modifieds, Sprint Cars that don't use a stock cross member location. The highly effective tray door system and the quick release windage tray assembly that is fastened into the pan provide 100% oil control at all times. This results in consistent oil pressure both in and out of the corners, as well as increases power output. Accepts stock large diameter flywheels. A sealed, dirt proof, screw in style dipstick and temperature sender bung are also welded into the pan.
Pan will fit a 4" stroke crank and Carillo or Eagle style rod.

Pan Capacity is 7 Quarts Plus Filter -
12" Sump Length, 7" Sump Depth
Left Hand, without dipstick 31504
Left Hand, with dipstick 31525

Oil Pump and Pick-Up Required:
Pickup with Milodon 18770 or Melling M99HV 18305
Pickup with Milodon 18750 or Melling M55HV / 10550 18306
Oil Pump 18750
Pump Drive Shaft 23050
Oil Pan Gasket 40100
Oil Pan Gasket, 1 piece, 41000
Rear Pan Baffle 32500
Oil Pan Bolts, vibration resistant 85000
related info, you'll want to read thru



attachment.php

sbcvsbbcgears.jpg


keep in mind the sbc oil pump has 7 tooth gears and the big block pumps have 12 teeth making the oil flow smoother and less pulsed, plus having larger gears they tend to supply more oil at lower rpms
look closely and youll see the big block oil pump has a 5 bolt lower cover and the oil pump pick-up with its 3/4" feed seats into the main pump casting while the small block oil pump has a 4 bolt cover and the sbc oil pump pick-up with its 5/8" feed seats into the pumps cover plate

look at the picture below, the restrictive stock O.E.M. pickup if placed to close to the oil pan floor becomes a HUGE restriction to oil flow rates
bbcoilpumpcover.jpg




as many of you gentlemen know MELLING CHANGED the casting on their standard M55 high volume oil pumps making them weaker and thinner
m55vsm1055t.jpg
M55tom1055at.jpg

sbcpumpgearxa.jpg

m10553vsM10552.jpg


http://www.hotrod.com/articles/ccrp-0911-small-block-chevy-oil-pumps/

OilPumpCoverC.jpg


SHARK-08.jpg

like the thin casting on the left
but I understand that it caused a good deal of bad press and they are currently changing back to the thicker castings, but theres still thousands of the thin casting pumps in inventory that should not be use in high performance applications

OilPumpBroke.jpg

M55tom1055at.jpg
m55vsm1055t.jpg

did you replace the oil pump drive shaft?
theres three common lengths in those oil pump drive shafts
theres a difference in length between the drive shaft used for a common sbc oil pump,
the drive shaft used for a BIG BLOCK oil pump in a SMALL BLOCK APPLICATION,
and a BIG BLOCK oil pump drive shaft length
all can be placed in a small block,or a big block but only the correct length will function in each application
tallpump.jpg


differancesbcbbc.gif


theres a difference between the sbc and bbc drive shaft designs so don,t mix them up
theres MARK IV and MARK V BBC oil pump drive shafts that differ also
theres both BBC and SBC oil pump drives and a less common oil pump drive shaft designed for using a BBC oil pumps in a SBC application thats length is between those lengths
arp-134-7901_w.jpg

oil pump drive shafts can be custom machined, to gain clearance, you should have about .050 clearance with the distributor seated

The oil pump drive shaft on the left fits any
Gen. I smallblock except the 400. The 400
shaft on the right is necked down in the center
portion to clear the wider main caps found on
the 400.
oil_pump_shaft.gif

148_0506_how_09_z.jpg

the aftermarket drive shafts are held to a much higher strength tolerance, and a steel collar and and the reduced mid section are both good features, for the very low price Id strongly suggest pitching the stock drive shaft in the dumpster
be sure you select the correct oil pump drive shaft
SB - is a bit shorter about 5.75"
BB - is a bit longer about - 6.50" or so
there should be about .050 vertical movement, of the oil pump, oil pump drive shaft between the oil pump and lower distributor gear with the manifold and distributor seated correctly

Small Block Chevy Oil & Lubrication Systems
The Chevy smallblock lubrication system is very reliable and presents no design defects to worry
about. Just keep everything clean. Change the oil and filter on a regular basis, and it will provide good
service for more than one hundred thousand miles. If the recommended main and rod bearing and
rod side clearances are maintained, a stock volume oil pump is all that is required. A high-volume or
high-pressure pump or an oil pump from a bigblock Chevy are not needed in most street applications.
These other pumps take additional horsepower to run and add more strain on the cam/distributor
drive gears and drive shaft. Checking the operating clearances on the stock oil pump and optimizing
them if necessary, will ensure adequate oil pressure. The clearance between the pump gears and the
pump gear cover should be .002" to .0025". If there is more clearance, take a sheet of 400-grit
sandpaper and some oil, then move the main pump body in a figure-8 motion over the wet sandpaper
to remove material until the clearance is correct. If there is less than the minimum clearance, you can
sand the pump gears. Remember to Loctite the pump cover bolts when you put the pump back

http://www.summitracing.com/search?keyword=5556F&dds=1
(chevy small block oil pump bye-pass springs)

http://www.summitracing.com/parts/mel-77060
(chevy big block oil pump bye-pass springs)

GM Small Block Performance Pumps
10550

High volume performance upgrade for M-55HV.
25% increase in volume over stock oil pump.
The 10550 housing and cover are CNC machined and phosphate coated.
The lower pressure spring is included to reduce pressure if desired.
Includes intermediate shaft with steel guide. Uses 5/8” press in screen.





10551

High volume performance upgrade for M155HV.
25% increase in volume over stock oil pump.
The 10551 housing and cover are CNC machined and phosphate coated.
The lower pressure spring is included to reduce pressure if desired.
Includes intermediate shaft with steel guide. Uses 3/4” press in screen.





10552

High volume performance oil pump.
10% increase in volume over stock oil pump.
The 10552 is manufactured with the drive and idler shafts extended to allow for additional support in the cover eliminating dynamic shaft deflection at increased RPM levels.
The cover is doweled to the pump housing to assure alignment of the shaft bores.
Screw in plug retains relief valve spring instead of pin.
Relief hole in cover uses screw in plug instead of pressed cup plug.
All bolts are self locking socket heads, with the wrench supplied.
The housing and cover are CNC machined and phosphate coated.
Includes intermediate shaft with steel guide. Uses both 3/4” bolt on or press in screen.
The lower pressure spring is included to reduce pressure if desired.
Patent No. 5,810,571.

10552C (Anti-Cavitation)

10552CHigh volume performance oil pump.
10% increase in volume over stock oil pump.
Same as the 10552 with the addition of grooves machined in the body and cover. The grooves reduce cavitation effects in high RPM applications.
Includes intermediate shaft with steel guide.
Uses both 3/4” bolt on or press in screen.
Using this oil pump will reduce pressure at idle.
The 10552C uses the high pressure spring only.
Racing Applications Only.
Patent No. 5,810,571.

10553

10553High pressure performance upgrade for M-55 & M-55A.
Standard volume oil pump.
The 10553 housing and cover are CNC machined and phosphate coated.
Manufactured with pink spring installed for higher pressure (M-55A).
To change pump to lower pressure (M-55) install the supplied yellow spring.
Includes intermediate shaft with steel guide.
The 10553 uses a 5/8” press in screen.



10554

Performance upgrade for M155. Standard volume oil pump.
The 10554 housing and cover are CNC machined and manganese phosphate coated.
Manufactured with pink spring installed for higher pressure.
To change pump to lower pressure install the supplied yellow spring.
Includes intermediate shaft with steel guide.
The 10554 uses a 3/4” press in screen.



10555

High Volume performance upgrade for the 10550 oil pump.
25% increase in volume over stock oil pump.
The 10555 is manufactured with the drive and idler shafts extended to allow for additional support in the cover eliminating dynamic shaft deflection at increased RPM levels.
The cover is doweled to the pump housing to assure alignment of the shaft bores.
Screw in plug retains relief valve spring instead of pin.
Relief hole in cover uses screw in plug instead of pressed cup plug.
All bolts are self locking socket heads, with the wrench supplied.
The housing and cover are CNC machined and manganese phosphate coated.
Includes intermediate shaft with steel guide.
Uses both 3/4” bolt on or press in screen.
The lower pressure spring is included to reduce pressure if desired.
Patent No. 5,810,571


10555C (Anti-Cavitation)

High volume performance upgrade for the 10550 oil pump.
25% increase in volume over stock oil pump.
Same as the 10555 with the addition of grooves machined in the body and cover. The grooves reduce cavitation effects in high RPM applications.
Includes intermediate shaft with steel guide.
Uses both 3/4” bolt on or press in screen.
Using this oil pump will reduce pressure at idle.
The 10555C uses the high pressure spring only.
Racing Applications Only.
Patent No. 5,810,571



10990

High volume performance upgrade for the M-99HV-S. ($144 price is outrageous in my opinion)
Increase in volume of 25% over stock oil pump.
The 10990 is a Big Block style oil pump made to fit the Small Block applications.
The drive and idler shafts have been extended to allow for additional support in the cover. Additional support eliminates dynamic shaft deflection at increased RPM levels.
The cover is doweled to the pump housing to assure alignment of the shaft bores.
The relief valve has a screw-in plug instead of a pin.
The housing and cover are CNC machined and phosphate coated.
An additional spring, the original stock replacement is supplied which will reduce bypass pressure if needed.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.
Patent No. 5,810,571.


10990C (Anti-Cavitation)

High volume performance upgrade for the M-99HV-S.
Increase in volume of 25% over stock oil pump.
The same as the 10990 except with the addition of grooves machined in the housing and cover. The grooves reduce cavitation effects in high RPM applications.
Using this oil pump will reduce pressure at idle.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.
Racing applications only.
Patent No. 5,810,571.




GM B.B. Performance Pumps


10770

High volume performance upgrade for M-77HV.
25% increase in volume over stock pump.
The housing and cover are CNC machined and phosphate coated.
The lower pressure spring is included to reduce pressure if desired.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.



10774

10774Standard volume performance upgrade for M-77.
The housing and cover are CNC machined and phosphate coated.
The lower pressure spring is included to reduce pressure if desired.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.




10778

High volume performance upgrade for the 10770.
Increase in volume of 25% over stock oil pump.
The drive shaft has been manufactured from chrome-moly steel.
The drive and idler shafts have been extended to allow for additional support in the cover. Additional support eliminates dynamic shaft deflection at increased RPM levels.
The cover is doweled to the pump housing to assure alignment of the shaft bores.
The relief valve has a screw-in plug instead of a pin.
The housing and cover are CNC machined and phosphate coated.
An additional spring, the original stock replacement is supplied which will reduce bypass pressure if needed.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.
Patent No. 5,810,571.


10778C (Anti-Cavitation)

High volume performance upgrade for the 10770.
Increase in volume of 25% over stock oil pump.
The same as the 10778 except with the addition of grooves machined in the housing and cover. The grooves reduce cavitation effects in high RPM applications.
Using this oil pump will reduce pressure at idle.
Includes intermediate shaft with steel guide.
Uses 3/4” press in screen.
Racing applications only.
Patent No. 5,810,571



RELATED INFO
http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.com/index.php?threads/cam-bearing-install-tools-install-info.1479/

http://garage.grumpysperformance.com/index.php?threads/installing-an-oil-pump-pick-up-tube.1800/

http://garage.grumpysperformance.com/index.php?threads/bearings-and-oil-flow.150/

http://garage.grumpysperformance.co...oil-passages-and-improved-oil-flow-mods.3834/

http://garage.grumpysperformance.com/index.php?threads/testing-a-chevy-oil-pump.6479/


viewtopic.php?f=54&t=2598

http://www.hotrod.com/how-to/engine/ccrp-0911-small-block-chevy-oil-pumps/



the difference between a stock capacity BBC and high volume SBC oil pump is minimal,
in the power needed to drive either one, you can use either, oil pump,
Ive used several standard volume bbc oil pumps in SBC engines but the stock z28 SBC oil pump works very well.
neither pump will require anywhere close to 10 hp,the tests Ive seen show closer to 2hp at peak rpms for either oil pump.
significantly less with normal .002-.003 clearances and hot 10w30 oil.

you certainly do not reed a high volume BBC oil pump on a SBC engine
obviously bearing clearances, oil viscosity , oil temperature,and the other lube system mods will effect the power required to spin any pump,

heres a calculator, if you put in the typical 6 gallons a minute at 65 psi you get less than 1 hp required
http://www.wallaceracing.com/oil-pump-hp-calc.php

http://www.badasscars.com/index.cfm/page/ptype=product/product_id=91/prd91.htm


http://www.wallaceracing.com/oil-pump-hp-calc.php

http://www.badasscars.com/index.cfm/page/ptype=product/product_id=91/prd91.htm


Are high volume oil pumps OK to run on the street?


prd_91.jpg


We get asked this one from time to time, and the answer is, it depends on the engine. First off; why do you think you need to run a high volume oil pump? The reason performance and race engines use them is because the clearances are upwards of twice the amount as a stock engine. Those voids flow oil out much quicker so they need more volume to stay filled with oil.

A typical stock engine has about .001" - .0015" of rod and main bearing clearances. When you get into more serious engines you will find rod clearances as much as .002" or more, and crank clearances upwards of .0025" - .003" or more. This is also why in the older days, race and performance engines used to run much thicker oils to help "take-up" all of that space. It was common to see straight 40wt and 50wt race oils in engines back in the day. Now days, with much better oils, we tend to run tighter clearances and much thinner oils. We've learned that thinner oil gets to where it needs to go much quicker and with less effort than thicker oils. Larger clearances on serious performance and race engines drain-out quicker so you need a pump that'll push more oil volume into them to keep those larger clearances full. Stock or mild performance engines don't really require that much oil flow because the clearances are much less and therefore "flow" oil much less.

You can't pump oil where it doesn't want to go. In other words, unless your crank and rod clearances are a lot more than a stock engine, then oil simply isn't going to flow and all you are going to do is make a lot of oil "pressure" but not much additional "flow". There's a HUGE difference between "pressure" and "flow". Contrary to what most guys believe, pressure is actually the negative result of flow. If you had full flow, you would have very little oil pressure. What happens when you eat a rod or main bearing? Your .001" - .003" clearance got chewed-up and is now .020" - .030", or basically ten times more than it is supposed to have, so now you have a huge amount of clearance that oil is just POURING out of. It's like slicing into an artery in your body, blood openly flowing out drops your blood pressure.

Other than the noise of a knocking rod or a squeaking "spun" main bearing, how can you tell when you have a bad bearing problem? The pressure reading on your oil pressure gauge drops WAY down. This is because you've opened-up that clearance way too far and now oil is just pouring out that huge space, which causes the pressure to drop way down. So, you increased the flow, and as a result, decreased the pressure.

Pressure can basically be looked at as "effort". How much effort is the pump going through to push that oil. The thicker the oil, the more the effort, and... the tighter the clearances, the more the effort to push oil into those tight spaces. Just because there is effort there (higher oil pressure) doesn't mean more oil is actually flowing. This again is especially true with thicker oils and why thicker oils create more oil pressure. Let me put this is terms even a kid can understand. Go to the local fast food joint and buy 2 drinks. One soft drink and one milk shake. Take a sip through the straw of the soft drink, now take a sip from the milk shake. It's a hell of a lot harder to sip that thick milk shake up through that straw than it is to sip-up that watery soft drink, right? Oil pumps and oil thicknesses are no different. You increased your effort to sip that milk shake and yet got much less of it into your mouth than you did the soft drink. That's exactly the same thing with oil pressure and oil flow vs. clearances and oil thicknesses, vs. oil volumes and pressures. if you want more milkshake with less effort, get a bigger diameter straw, which is like opening-up clearances on your engine, OR wait until the milkshake gets a bit warmer and thins down a bit. This is exactly like oil pressure dropping when your engine warms-up. It's because the cold, thick oil is requiring more effort (pressure) to push it into those clearances, but when it warms-up and gets thinner, it requires even less pressure, yet your FLOW increased. People seem to think this is such a complicated subject, but it really isn't at all.



Another thing is that higher volume oil pumps put much higher loads on the gears that are driving them, meaning the distributor and cam gears. Chevy engines can handle the higher loads of high volume oil pumps just fine, where most Ford's have troubles. Why? Chevy's use a much larger gear than a Ford does, in fact, it's about twice the size, which means it's about twice as strong. The distributor gear is what takes the load of spinning the oil pump. The more volume you pump through an engine, the more load gets put on that gear.



Ford gears tend to get eaten-up because they just aren't big or strong enough to take the load that a high volume pump puts on it. Once you eat-up a distributor gear it is pretty much disaster for the cam gear as well. If you wipe either one out, count on having to replace the cam shaft! This doesn't even get into all of that metal going through the engine, which doesn't help things like bearings and such.


prdp_578.JPG

We tend to use stock oil pumps on Ford's and high volume pumps on "performance" Chevy's where the clearances were opened-up a bit. On race prepped Ford engines that we run high volume pumps on, we use aluminum-bronze gears and just keep a close eye on them for premature wear because they WILL wear out in a short amount of time. In fact, that's what aluminum-bronze gears are designed to do... wear-out instead of the expensive cam wearing out on you. Technology has advanced a little these days with the invention of composite gears. They aren't made out of metal, they're made out of a material that is kind of like carbon fiber and are practically indestructible. The cool thing is they are compatible with all types of cams, from cast iron to billet steel, where before... if you didn't have the right type of gear on your distributor to match the type of cam you had, you were looking at disaster in a short amount of time.

When the 5.0L engines came-out with steel roller cams, they also went to steel distributor gears which are much stronger than the older cast iron gears, but they are still about half the size of a GM gear, so it is still about half the strength, which means you still have to be careful if you want to run a high volume pump. A lot of guys get away with it, but that's just it... they're "getting away with it". In other words, we still see a lot of guys NOT get away with it and then they have a serious and expensive problem to deal with. Going back to everything I explained above, did they really even NEED a high volume pump in the first place? Most likely not. If they wanted more flow, they should have probably just ran a thinner oil which would have increased the flow and not put undue loads on the cam and distributor gears.


Now, some people will say to run a stock pump because it won't rob as much power from the engine as compared to a high volume pump, but they install the "high pressure" spring in it to make more pressure. In some cases, pressure makes volume, but again, volume = load. If you ever forget to hook-up your oil pressure gauge line and you fire the engine up, you are going to have a LOT of oil coming out of that tiny little 1/8" line because of the pressure behind it. If there was very little pressure, not much oil would come out. Like I said; pressure makes volume IF there is a means for flow. But again, pressure increases load.

Some people say that a high volume oil pump will pump all of the oil to the top of the motor and basically empty out the oil pan before it can all drain back again. On some engines, such as Oldsmobiles where oil drain back through the heads is a common problem because of the long - small diameter drain back holes, so in cases like that this "could" have some slight truth to it, but 98% of the time, it has no basis. First off; high volume oil pumps only pump about 15% to 20% more oil than a stock pump does. So that would mean that your stock pump is only 15% - 20% away from sucking your oil pan dry. That's highly unlikely. Again, running thicker oils means draining back through long, skinny holes in some of the heads out there (such as Oldsmobiles) MIGHT be an issue because just like that thick milkshake I mentioned earlier, if you turned both the soft drink and the milk shake cups upside down, which one will pour through the straw better than the other? It would probably take (literally) a minute or two for the thick milkshake to even start to dribble out of the straw under gravity conditions, where by that time, the entire soft drink cup would be completely empty. Thicker oils and small drain back holes in heads would have similar results, but in most cases, most engines have plenty of oil drain back holes and areas, so it isn't a problem most of the time.

In a nutshell, 95% of all engines out there, whether stock or mild performance (under 550 HP or so) will do just fine with standard oil pumps, especially if a little thinner oil is used and if the clearances that aren't too loose.
 
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you should NEVER shim an oil pumps pressure relief spring as it may prevent the piston it holds from moving down its bore far enough to allow it to open the bay-pass passage, that allows the pressure on the high pressure side of the oil pump from bleeding off back into the intakes side of the oil pump
there are oil pump testers available commercially or if your mechanically inclined you can fabricate one with reasonable care, after a bit of measuring and purchasing a gauge, if you don,t test you won,t know whats going on,

http://cvrproducts.com/oil-pressure-test-kit/
oilpumptesterdd.jpg


you should NEVER shim an oil pumps pressure relief spring as it may prevent the piston it holds from moving down its bore far enough to allow it to open the bay-pass passage, that allows the pressure on the high pressure side of the oil pump from bleeding off back into the intakes side of the oil pump, the springs come in several resistance strength levels, but extensive testing has shown now increased bearing protection at pressure levels exceeding 65 psi, higher strength pressure relief springs, just increase engine rotational resistance

http://www.summitracing.com/parts/mel-77070/overview/
Oil Pump Springs, 70 psi, Steel, Pink, Pins, Chevy, Big Block, Kit

http://www.summitracing.com/parts/mel-7760m/overview/

http://www.summitracing.com/parts/stf-35250/overview/

oilspring.jpg


Melling 55070
70 psi, Steel, Pink, Pins, Chevy, Small Block, Kit
Melling 77070
Oil Pump Springs, 70 psi, Steel, Pink, Pins, Chevy, Big Block, Kit
Melling 55058
Oil Pump Springs, 58 psi, Steel, Yellow, Pins, Chevy, Small Block, Kit
Melling 55078
Oil Pump Springs, 78 psi, Steel, Green, Pins, Chevy, Small Block, Kit
Melling 77060
Oil Pump Springs, 60 psi, Steel, Black, Pins, Chevy, Big Block, Kit
Melling 55049
Oil Pump Springs, 49 psi, Steel, Green, Pins, Chevy, Small Block, Kit
Melling 77052
Oil Pump Springs, 52 psi, Steel, Purple, Pins, Chevy, Big Block, Kit
Melling 7770M
Oil Pump Springs, 70 psi, Steel, Pink, Chevy, Big Block, Set of 5
Melling 5556F
Oil Pump Springs, 55 psi of Force, Steel, Chevy, Small Block, Set of 5
Melling 5570F
Oil Pump Springs, 70 psi, Steel, Pink, Chevy, Small Block, Set of 5
Melling 7760M
Oil Pump Springs, 60 psi, Steel, Black, Chevy, Big Block, Set of 5
Melling 7752M
Oil Pump Springs, 52 psi, Steel, Purple, Chevy, Big Block, Set of 5
Melling_Spring_Specs.jpg

Many pressure relief springs have one end larger than the other end,the spring always mounts with the larger end facing away from the bypass piston, if installed reversed the piston can,t move far enough to completely open the bypass circuit passage and pressures skyrocket, under some conditions
http://www.summitracing.com/search?keyword=5556F&dds=1
(chevy small block oil pump bye-pass springs)

https://www.hotrod.com/articles/ccrp-0911-small-block-chevy-oil-pumps/


While reading several books on building performance engines I found one recurring message – stick with the stock big block oil pump! Apparently these pumps have a solid reputation for being bulletproof. Here’s what the stock oil pump looked like after a thorough cleaning.



1.jpg
Oftentimes people replace the stock oil pump with a high flow or high pressure aftermarket pump as a matter of course when completing an engine build. However, much of my research seriously questioned this practice and made a compelling case in the process. First, for street and street performance use the stock oil pump is perfectly capable of pushing more than enough of oil (provided the correct main bearings are used and that bearing clearances are not ridiculously large). Secondly, high pressure and high volume pumps certainly do push a lot of oil, but much of that oil is simply forced out of the pressure release valve and never makes it through the engine. Also, don’t forget that pushing all that extra oil takes more work and more horsepower. Lastly, although a high volume pump could easily have been provided by GM engineers, they didn’t feel it was necessary – even on the high performance L-88 and ZL-1 models. With that in mind I started checking my stock pump to see how it looked, overall it was in very good condition. Below is a photo of the pump with the cover removed.




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Disassembly of the pump is quite simple, the parts are all slip fit so they’re easily removed. Prior to removing the drive and idler gears I marked their relative position so that they could be reinstalled in the same orientation.




3.jpg
Despite the bullet-proof reputation of the stock big block oil pump several of my references recommended a few minor modifications when using them in a performance application. After giving this some consideration I opted to go ahead and make the modifications as they were explained and outlined in the book “How to Hotrod Big-Block Chevys”. The book is a good reference, although it’s a bit dated, but it provides some good info nonetheless. Considering used copies can be had for less than $10 it’s certainly a worthwhile investment.




hotrod.jpg
First on the list of modifications was to lightly chamfer the edges of the gear teeth with a file.




4.jpg
Next, and perhaps the scariest modification, was pressure balancing the oil pump. By creating small grooves in the pump housing the hydrostatic forces on the idler and drive gears can be more evenly distributed. This reduces the amount of pulsating forces that are transmitted up the oil pump drive shaft and ultimately into the distributor. Although not a major problem, this pulsating has been known to contribute to spark scatter (changes in timing) at high RPM. The pressure balancing also helps prevent cavitation and allows the pump to operate more efficiently and on less horsepower. GM engineers provided some of these pressure balancing grooves on their high performance pumps (used on L-88 Corvettes), but these modifications go a step further. Having said that, below I’ve laid out the locations of the pressure balancing grooves on the pump housing.




6.jpg
To make the grooves I used a Dremel tool with a bit intended for chain saw blade sharpening. The size of the bit (5/32″ diameter) was just about the perfect size and it worked very well.




5.jpg
After a few hours of careful work the grooves were complete. Below is a picture of the modified housing. Note that care needs to be taken to assure the grooves in the cover (#1 & #2) need to line up with the vertical grooves on the pump housing (#1 & #2). The other two red arrows are meant to point out vertical grooves in the pump housing (a bit hard to see in the photo).




7.jpg
Lastly, and probably most importantly, the proper end clearance between the gears and pump housing cover needs to be established. Excessive clearance results in poor priming ability and inefficient pump operation. Ideally end clearance should be about 0.0025 inches. If excessive clearance is found the housing can be sanded down by using a piece of fine to medium grit sandpaper placed on a flat, hard surface. Be sure to apply even pressure and rotate the pump often during this process to ensure material is removed evenly. Conversely, if the clearance is too small the gear height can be reduced by using the same sanding procedure above.




8.jpg
After establishing the proper clearance and a very, very thorough cleaning I reinstalled the pump cover and screws using Loctite on the screw threads. That’s all for this update!
 
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