Unforgiven Project

Thought this might be of value :

Oil plug under SBC rear main cap
One plug that can be easily forgotten is the plug located "under" the rear main cap (as viewed with the engine block on an engine stand in position to install the plug). Without the plug, the oil will not be filtered. Contrary to popular belief, there will still be oil pressure, although it may be somewhat reduced. Or possibly no change.

[edit]Checking block for plug
If there is any question whether the plug is in place inside an assembled engine, a straight piece of wire can be used (like piece of brazing rod) to check the depth of the plug in the block. By going down the oil sender hole at the rear of the block, the plug should be located between 8-3/8" and 8-1/2" down.

If the rod extends down further, that would indicate the plug is missing. If the rod is short of this, it may be installed wrong and could block off oil flow.



Oil filter bypass plug location


Plug location details
Plug dimensions and part numbers
1985-back with 2-piece rear main seal
The plug is a 1/2" OD (0.520”-0.536" OD x 0.300" deep) steel expansion plug. GM part number is 3701638 (Pioneer EPC-87, Dorman 555005). The passageway can be tapped for a 1/4” NPT plug; this requires a long tap to reach the area that needs to be threaded.

1986-up with 1-piece RMS
Some engines used a steel ball instead of a cup plug. These engines are the 1986-up 1-piece RMS blocks including the Gen 2 LT1. These blocks can’t be easily tapped for a 1/4” NPT plug, the hole is smaller than the 1/2" ball or cup plug used in 1985-back Gen I SBC blocks with 2-piece RMS. The ball can be replaced with a cup plug; the cup plug part number for these '86-up 1-piece RMS blocks is Pioneer EPC108.
 
those oil pans generally work out well...
cantonoill.jpg


IF the front cross member allows the required clearance for the pans installation
be aware theres
right and left dipsticks
and thick and thin front seals,
and one and two piece rear seals
ONE PIECE OIL PAN GASKETS
1974 and earlier pans had a shallower/thinner front gasket opening where the pan meets the timing chain cover and 1975 and later used a deeper/thicker pan gasket in this area, the 1985 and some other blocks used the right hand dip stick further complicating things

theres two common gasket thickness measurements,Put a straight edge across the front of the oil pan and measure down to the lowest part of where the seal rests directly centered under the crank,the distance from the strait edge to the lower front oil pan is the measurement you need,. It's the oil pan that determines thick or thin seal, not the timing cover.

IVE GENERALLY HAD THE BEST RESULTS WITH ONE PIECE OILPAN GASKETS AND USING STUDS
http://www.summitracing.com/parts/mor-38360
bbcstudz1.jpg

http://www.summitracing.com/parts/mor-38350
sbcstudz1.jpg

2-1/4" = thin seal
2-3/8" = thick seal
HERES A BASIC LIST (SBC)
SMALL BLOCK FELPRO

Fel Pro #375-OS34510T
Replacement Oil Pan Gasket
PermaDryPlus
1975-85 SBC 262-400
Right-hand dipstick


this while deal is not that difficult
youll obviously need a damper puller tool
http://garage.grumpysperformance.com/index.php?threads/harmonic-balancer.3554/#post-53706
http://garage.grumpysperformance.com/index.php?threads/damper-honing.4975/#post-13912
http://www.jegs.com/i/JEGS-Performance-Products/555/W89711/10002/-1
harmonic3.jpg

pang.png

Fel Pro #375-1880
H/P Oil Pan Gasket
PermaDryPlus
1975-79 SBC 262-400 (side rails cut for Strokers)
9/64" thick
Thick Front Seal
Left-hand dipstick

Fel Pro #375-1881
H/P Oil Pan Gasket
PermaDryPlus
1980-85 SBC 262-400 (side rails cut for Strokers)
9/64" thick
Thick Front Seal
Right-hand dipstick


Fel Pro #375-1882
H/P Oil Pan Gasket
PermaDryPlus
SB-Chevy & race blocks with straight side rails
9/64" thick
Thick Front Seal

Fel Pro #375-1885
H/P Oil Pan Gasket
PermaDryPlus
1957-74 SBC 262-400
9/64" thick
Thin Front Seal
Left-hand dipstick

Fel Pro #375-OS-34509T
Replacement Oil Pan Gasket
PermaDryPlus
1957-74 SBC 262-400
Thin Front Seal
Left-hand dipstick


Fel Pro #375-OS34500R
Replacement Oil Pan Gasket
Rubber-coated/steel core
1986-99 SBC 305-350




Fel Pro #375-OS34510T
Replacement Oil Pan Gasket
PermaDryPlus
1975-85 SBC 262-400
Right-hand dipstick
HERES A BASIC LIST (BBC)

Fel Pro #375-1884R
H/P Oil Pan Gasket
PermaDryPlus
1965-90 BBC 396-454
3/32" thick



Fel Pro #375-OS34407R
Replacement Oil Pan Gasket
Rubber-coated/steel core
1991-2000 BBC 454

Fel Pro #375-1893 (THREE PIECE)
H/P Oil Pan Gasket
Rubber-coated/steel core
1965-90 BBC 396-454
1991-Up BBC 454-572
Side rails cut to clear rods

Fel Pro #375-1863
Replacement Oil Pan Gasket
Rubber-coated multipiece
Donovan-Merlin blocks


BIG BLOCK MOPAR

Fel Pro #375-1834
H/P Oil Pan Gasket
Rubber-coated/steel core
1958-79 361-440 & Hemi
3/32" thick



http://www.jegs.com/webapp/wcs/stores/s ... 4_-1_10197

http://www.jegs.com/i/Milodon/697/41000/10002/-1

TWO PIECE REAR SEAL

OS34509T: Thin seal

OS34510T: Thick seal

BOTH LEFT HAND DIPSTICK
looks like you need the #OS34509T: Thin seal,if you need a thin front seal
but that only comes in left hand
so you might be forced to use
the older 4 piece design if you need a thin seal and right hand dip stick

Right-hand dipstick
375-1818

have the Felpro catalog and they show 5 SBC one piece gasket part numbers:

PN1881 1980-85 thick front seal RH dipstick; side rails trimmed for strokers
PN1880 1975-79 thick front seal LH dipstick; side rails trimmed for strokers
PN1885 1957-74 thin front seal LH dipstick
PN1882 Thick front seal straight side rails; side rails trimmed for strokers
PN1886 1986-97 thick front seal, one 1pc rear main seal GM bowtie short deck block
________

per jegs #'s FEL-PRO SMALL BLOCK CHEVY
1957-1975 1 piece 37.99 #1885
1986-1997 1 piece 39.99 #1886

MR.GASKET SMALL BLOCK CHEVY
1975-1985 1 piece 27.99 #6560
1986-1996 1 piece 27.99 #6561

http://www.jegs.com/webapp/wcs/stores/s ... 2_47050_-1

one-piece main seal blocks use this one:
OS34500R

Which type you use is dependent on your oil pan, not the block or timing cover.


BBC LISTED ALSO

http://www.jegs.com/webapp/wcs/stores/s ... 4_-1_10197

http://store.summitracing.com/egnsearch ... 5&y=8&x=43

http://garage.grumpysperformance.co...main-seal-in-a-gen-i-chevy-v8.1718/#post-4257

keep in mind on big blocks theres mark IV, mark V and MARK VI oil pan gaskets

Grumpy, what should you torque the bolts to and in what pattern?

this should help, (I generally snug the bolts up on the oil pan by feel and don,t over tighten them, and I generally use a small 1/4" drive ratchet to do so, not a tq wrench, (I think its 14-15 ft lbs or 165-170 inch lbs if you want to get technical) Im sure theres a specification, your supposed to use but Ive seldom had any problems just snugging them up by the feel with a short 1/4" drive ratchet.) I generally tighten in stages and constantly circle the pattern, I think the main problem occur when guys OVER TIGHTEN and crush the gaskets, snug but not tight works, if the gaskets being squished out noticeably between the block and pan lip, your more than likely over tightening the bolts, heres where experience comes into play, if your not sure use a inch rated tq wrench at 170 inch lbs

http://www.digitalcorvettes.com/forums/showthread.php?t=81323

http://www.small-block-chevy.com/assemblyspec.html

http://www.gmpartsdirect.com/performanc ... D=968.html

http://www.sallee-chevrolet.com/oilsystem/index.cfm

http://garage.grumpysperformance.co...epair-leaking-oil-pan-drain.13652/#post-70344

BTW oil pan rails are flimsy on some oil pans
ID check the oil pan rails are not bent/warped and if you need to use some black silicone sealant, but Ive never yet had that be necessary, most leaks are the result of EITHER the gasket not being seated correctly or over tightening the bolts bending oil pan.

On oil pans I prefer studs, and an oil pan back plate
panback1.jpg

fel-0534510t.jpg

you might want to Use with P/N 12553058 RH and P/N 12553059 LH oil pan reinforcement plates to distribute the bolt stress on the oil pan rail for 1985 and earlier oil pans P/N 14088501 (LH) and P/N 14088502 (RH).1986 and newer
always use the manufacturers suggested installation instructions, as some applications or gasket types REQUIRE different lubes or sealants but heres a rough guide, you need to carefully clean and degrease any contact areas where sealants are to be used.
heres a rough guide to help select the correct sealants
yes any component needs to be properly installed, I've seen something similar happen a few times in the past, (persistent slow oil leaks) when guys were using a crank scraper sandwiched between the oil pan gasket and the block,
when guys simply forgot to spray both of the crank scraper surfaces and the block and gasket surface with some sealant like copper coat. hot oil is DESIGNED and formulated to seep into and through small cracks , and if there's no sealant blocking that hot liquid penetrating oil, it will eventually find its way through micro cracks in the area between two metal surfaces, so you,ll want to coat both sides of the gasket and crank scraper with a thin coat of spray sealant just prior to oil pan assembly
0804chp_12_z+pan_crank_scraper.jpg

409crankscraper.jpg

LubeV8_W_Scraper02.jpg



If you find you have an oil leak from the front of a chevy engine don,t assume its the front cover or lower timing cover seal leaking, be damn sure thats where the actual oil leak is, your oil pan and front cover and oil pan gasket being used, may not be properly matched to each other causing the leak, its very easy to buy a universal chevy sbc oil pan that may not match your year block or indicated fron seal but I find in many cases, its the front crank seal OR that common oil leak, from a lose or missing bolt, in the block ( read through all the links) and don,t ignore the fuel pump to block gasket as a potential oil leak point or valve cover of front intake rail gasket

MysteriousSmallBlockChevyOilLeak.jpg


this while deal is not that difficult
youll obviously need a damper puller tool
http://garage.grumpysperformance.com/index.php?threads/harmonic-balancer.3554/#post-53706
http://garage.grumpysperformance.com/index.php?threads/damper-honing.4975/#post-13912
http://www.jegs.com/i/JEGS-Performance-Products/555/W89711/10002/-1
harmonic3.jpg



http://garage.grumpysperformance.com/index.php?threads/tracking-down-an-oil-leak.1430/#post-3168

http://garage.grumpysperformance.co...l-pan-gasket-still-small-leak.3084/#post-8194

http://garage.grumpysperformance.com/index.php?threads/oil-pan-gaskets.206/#post-390

http://garage.grumpysperformance.co...ain-seal-in-a-gen-i-chevy-v8.1718/#post-11956

http://garage.grumpysperformance.co...stalling-the-intake-manifold-distributor.464/
http://garage.grumpysperformance.co...pans-that-fit-the-c4-corvette.3071/#post-8131

http://garage.grumpysperformance.co...ece-oil-pan-gasket-thickness.4578/#post-12188

http://garage.grumpysperformance.com/index.php?threads/oil-pan-gaskets.206/#post-1154

http://forum.grumpysperformance.com/viewtopic.php?f=51&t=1718&p=4257&hilit=+rear+seal#p4257

http://garage.grumpysperformance.co...ain-seal-in-a-gen-i-chevy-v8.1718/#post-33369

http://garage.grumpysperformance.co...-pan-gasket-still-small-leak.3084/#post-11971

http://garage.grumpysperformance.co...ling-an-oil-pump-pick-up-tube.1800/#post-4597

http://garage.grumpysperformance.co...oving-gaskets-the-wrong-way.10464/#post-43934

http://garage.grumpysperformance.com/index.php?threads/which-sealant-goes-where.700/#post-43768
 
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Thank you for the comments. I was a little nervous.



I plan on installing front and mid engine plates and moving the motor back a couple inches anyway.

This pan is for a newer one piece crank seal block. My new block is designed for a one piece seal and I am installing a rear seal adapter to
accommodate The 2 piece seal crank I already have.
This pan has the provisions to install a braided dipstick into the pan itself also. (this is a feature I really wanted)

I called cloyes today.... They told me that the cloyes timing chain I had bought along with the rotating assembly
is the correct set and will work with that block. This news saved me another $100. I like saving money!

I'll be back in the barn tonight fitting more rings. Can't wait to get out of the office today!!!
 
Wow! Thank you again for all the links and advise!
:)

Mike..... I found that EPC-108 plug at our local Advanced Auto store.
That is where Randy has his engine machine shop. He keeps alot of them on hand.
I will pick one up on my way home and get that little devil installed before I forget
about it.
 
I also found on the Canton website that the oil pick up tube for that pan, using a BBC M77 oil pump is part # 20-100

I was a little concerned that I was going to run into trouble trying to find one. Using a BBC oil pump on a SBC is new to me..
 
Last edited:
Unforgiven said:
I also found on the Canton website that the oil pick up tube for that pan, using a BBC M77 oil pump is part # 20-100

I was a little concerned that I was going to run into trouble trying to find one. Using a BBC oil pump on a SBC is new to me..
Click to expand...
It's a good idea with the Extra long run Remote oil to air cooler you have in the bed of your truck.
 
WELL.... I got a few more rings done and bagged last night. I fitted one of the plasma rings... Those plasma rings are HARD to grind, especially the last .001 ...
I can see how a guy could over grind easily if he was to start with the top rings first. It takes more pressure and more turns on the handle to grind the plasma top rings. The second rings are softer ductile iron, they require lighter pressure against the diamond wheel and LESS turns on the grinder handle.
So far, I have fitted 4 second rings and 2 top rings. Not in a hurry at all.
I am making sure that the gap is square and true. I can get a .026 feeler gauge to slide in nice, but a .027 will not go at all.

Also... that oil galley plug at Advanced Auto was a cross reference to the EPC-108 plug.
It is NOT the same style plug... I WILL NOT BE USING THIS PLUG!
It is shaped like a dish instead of a cup!
It could very easily tip in the bore if used.
This style of plug is used more for a dust cover .
The pic below is similar to what they had.

DSCN9971_b31652b1-f471-4355-bebe-ca125eb890d6_2048x.JPG


I will wait till I have enough parts to order , and purchase the exact plug that is needed thru Summit Racing.
This is one nice thing about downloading a build sheet.. You are able to keep track and record everything.
Hope to be back in the barn tomorrow after noon.
 
Just got done making this.

IMG_0373.jpg IMG_0374.jpg


I will epoxy small magnets I have at home , in the feet. I have it so the magnets are .020 recessed.
 
The wife had me busy this weekend with a major box that needed to be checked off her to-do-list... had to remove and install
a new front door. The brass side lights are next.

IMG_0378.JPG
 
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