oil pan gaskets

grumpyvette

Administrator
Staff member
now Im sure most of you guys have seen or used both types, (the old cork 4 piece sets and the newer synthetic one piece design oil pan gaskets)
in my opinion the newer synthetic one piece style is FAR superior!
if you read the instructions they say to not use a sealant, Ive found that use of contact cement ONLY on the surface between the upper gasket and blocks lower edge to be a better idea as you can slide the gasket in place then install the oil pan, especially if your under the car, but I also advise the use of STUDS in the BLOCK whenever you can use them as its so much more precise and keeps the gasket from moving as much during the installation procedure.Ive usually used the gasket with contact cement on the upper surface and studs to keep in located until the pans aligned and installed, because doing it way makes the installation far easier
BTW the 4 corner studs are a different diam. (larger) so keep that in mind and you don,t want the studs to extend to far below the block as it can cause clearance and installation problems if your sliding the pan on/off under the car with the K-member,
putting a dab of silicone sealant in the corners helps, and I generally use a product like these brush-on sealants on both the treads and both sides of the one-piece oil pan gaskets
(yeah it says you don,t need it)
80057.jpg

80063.jpg

mor-38350_w.jpg


viewtopic.php?f=51&t=1718&p=4257&hilit=rear+seal#p4257

viewtopic.php?f=32&t=699&p=972#p972

viewtopic.php?f=54&t=525&p=4599&hilit=clay#p4599

viewtopic.php?f=53&t=301&p=1815&hilit=+one+piece+crank#p1815

viewtopic.php?f=27&t=26

viewtopic.php?f=32&t=474&p=585&hilit=+synthetic#p585

http://store.summitracing.com/partdetail.asp?part=MOR-38350&autoview=sku

THIS MAY COME IN HANDY

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


viewtopic.php?f=54&t=65

viewtopic.php?f=52&t=761&p=1092&hilit=+sequence#p1092

and remember the oil pan will only clear that K-member with the crank counter weights in a single location, so if your having a caniption fit trying to get it to clear the K-frame the counter weights more than likely in the wrong rotational location, SPIN IT OVER A BIT TO CLEAR :thumbsup:


ONE PIECE OIL PAN GASKETS
fel-0534510t.jpg


HERES A BASIC LIST
SMALL BLOCK FELPRO

http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_746664_-1_10197

TWO PIECE REAR SEAL

OS34509T: Thin seal

OS34510T: Thick seal

http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_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/servlet/product_10001_10002_746664_-1_10197

http://store.summitracing.com/egnse...kets&searchinresults=false&N=700+115&y=8&x=43

thinthickseal.jpg

onepiece.jpg


rearmainseal6.JPG

here you can see the thin line of sealant under the rear main cap, thats sometimes overlooked resulting in a slow drip near the rear main seal

Vortec plastic timing cover replacement

by: Cobalt327
(Click here to edit this page anonymously, or register a username to be credited for your work.)

Contents
[hide]
[edit]Overview
The Vortec engine came with a plastic timing cover with a non-replaceable front crankshaft seal. Because of this, the recommendation is to replace the cover. If the cover wasn't leaking from the front seal there seems to be little reason not reuse it.

Otherwise, it is possible to swap to a steel cover in its place

[edit]Timing covers
Below is a side-by-side shot of a plastic cover from a 1997 Vortec engine and to the right of it is a '80s non-roller steel timing cover for comparison.



Using a '87-up steel timing cover w/the 1-piece oil pan gasket would be the best bet, although any steel or aftermarket cover may well work as well.

[edit]Timing cover differences
  • The plastic cover has more room around the crank gear to make room for the crank position sensor rotor
  • The steel cover is deeper, from inside the front to the sealing surface
  • Generally, there is more room around the inside of the steel cover, even though the photos don't show this very well due to how the covers are shaped and the angle the photo was taken
  • The plastic cover has fewer bolt holes at the top
  • The plastic cover has male pins or dowels to locate the cover onto the face of the block; the steel cover has holes in the same position for the dowels that are used in the older blocks
  • The plastic cover's bolts are shouldered to prevent over-tightening the cover
  • The p/n for plastic cover w/sensor hole is: p/n 10244600
  • The number for plastic w/o sensor hole is: p/n 12562818 (old p/n 12552557). This new design cover is used on all ZZ4 crate engines, and will bolt to any small-block Chevrolet engine from 1995 through current model except LT1/LT4 (Gen 2) and LSx engines.
[edit]Vortec block


Some blocks do not have all the timing cover holes; holes that may be missing are circled
A block using a steel cover uses dowel pins in the block, and has the locating holes in steel cover.

The Vortec block (right) does not use block mounted dowels to locate the cover. Instead, it has holes for the plastic cover's locating pins. The locating holes in the 880 block are >15/64" and <1/4", which is about right for a press-fit 1/4" dowel pin. That said, it's not presently known if the hole size is correct for a press fit solid steel dowel like used on the earlier blocks. As a precaution, the hole should be carefully measured before driving in a solid dowel to avoid cracking the casting. Another alternative is to use a 0.250" OD hollow roll pin to avoid stressing the casting. Also the timing cover flange is thicker - 5.7L cylinder blocks with the #880 casting will accept early and late timing covers.

The 880 Vortec block shown has all the holes present and tapped. This is not always the case; some blocks (those used with the 1996-02 C/K truck and vans to 2002 with the exception of those used for marine or industrial applications) are missing two holes and will need to use a gasket as a template to drill and tap the missing holes. (These blocks with the 2 undrilled timing cover holes will also have the water pump bypass hole and its corresponding hole on the RH block deck undrilled. Drilling the hole for the water pump bypass requires the use of a water pump gasket as a template (RH water pump hole) and a pre-Vortec head gasket (the hole is drilled at an angle). Fuel pump mounting boss area is usually unmachined (as with the previous 638 or 727 castings where the fuel pump pushrod hole is undrilled even if a factory blockoff plate was used). The timing cover bolt thread size is 1/4-20 (1/4" coarse), the pilot hole can be drilled with a #7 bit.

[edit]Gaskets and seals
The last thing that needs checked is the type of front oil pan-to-cover seal is needed. To check what front seal is needed, put a straight edge across the front of the pan and measure down to the lowest part of where the seal rests.

  • 2-1/4" = thin (early 1955-'74) seal, 3/32" thick
  • 2-3/8" = thick (later 1975-'85) seal, 9/64" thick
[edit]Dampers
The SBC damper has to be installed fully so it "sandwiches" the crank gear between the crank and the damper snout. If a damper from a 1995-back SBC is used, it will be long enough to work properly.

[edit]Vortec damper
The Vortec damper from a reluctor wheel-equipped engine is shorter by the thickness of the reluctor. So if a reluctor-equipped Vortec damper is used, a spacer made from the reluctor needs to be used if a steel timing cover is going to be used.

This is because the reluctor ring won't fit behind the steel cover. Without the spacer, the damper will go on too far and the pulleys won't line up, and the damper might even bottom out on the timing cover.

 
Last edited by a moderator:
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.
If you intend to remove the oil pan to check, or replace the oil pump or bearings with the engine still in the car,
be aware that the cranks front journal counterweights position may not allow you to slide the oil pan back out,
from under the engine and out,
over the front cross member and allow clearance required.
that oil pan may only slide out over the cross member,
only if the front crank counterweight is in the 12 o'clock location
and yes removing the motor mount bolts and jacking the engine up a few inches certainly tends to help
, but if you do, remove the distributor before you start,
more than a few guys ignored that bit of advice and the result gets darn expensive
and yes check the oil pump pick-up to oil pan floor clearance, if its not 3/8"-1/2" it will cause flow issues

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


do I put sealant on the oil pan gasket?

YES, even if it says no sealant is required I generally put a bit of sealant on both sides of the one piece synthetic oil pan gasket
DO NOT USE YELLOW 3M weather strip adhesive as it slowly dissolves in oil over months
80057.jpg

this stuff is pretty much interchangeable
80063.jpg


with this stuff in THAT APPLICATION
recommended operational temp range is just a tiny bit different from what Ive seen, one has about a 30F higher recommended temp, youll never get close in a properly operating engine to either
DisplayImagesd.asp.jpg


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/



BTW while you have that oil pan off you might consider a much improved oil pan install.
AS AN EXAMPLE,
several vendors have oil pans that are designed for road racing a 1984 corvette,
that feature a 6-7 quart baffled oil pan with much improved oil control
be sure you order the correct side dip stick oil pan and rear seal type,
if you go that route,
you could obviously add baffles and a larger sump to the existing oil pan,
if you have fabrication skills and a decent welder
be sure you consider your ground clearance and room for headers , oil filter etc, if you buy or modify your oil pan

,here as an option.

http://garage.grumpysperformance.com/index.php?threads/building-a-custom-wet-sump-oil-pan.65/
ctr-15-240tblk_xl.jpg


this is a good but more expensive option:D and you can always just re-install the stock oil pan if you buy a second oil pan,
versus risking ruining the stock oil pan if your fabrication/welding skills..:rolleyes: are somewhat less than ideal....:eek:
but you will feel a sense of satisfaction if you modify the existing oil pan correctly :Dand gain new skills

https://www.summitracing.com/parts/ctr-15-240tblk


 
Last edited by a moderator:
Re: one piece oil pan gaskets

No, you do not need to lift the engine to change the oil pan gasket, on a c4 corvette, but although it's actually a pretty simple job, its time consuming and experience helps a great deal


but the crank counter weights PREVENT the pan clearing the cross member in all but one location in the rotation and even then most guys find that loosening one motor mount to jack the engine up 1/4"-3/4" higher is just not that difficult vs constantly indexing the crank and pan., and a one piece gasket CONTACT cemented to the block & front timing cover before the pans installed smooths the process

BTW if your doing a cam swap , not an oil pan gasket replacement the synthetic oil pan gaskets tend to be far more durable
If you simply need to remove the timing cover,you can frequently loosen the oil pan ENOUGH , to allow the timing cover to be removed and replaced if you have the ONE PIECE SYNTHETIC OIL PAN GASKETS, if not the chances are much higher that the old cork, and rubber end piece style oil pan gaskets or front timing cover style gaskets might leak
 
Dang Grumpy, wish I had searched for this earlier - would have made my life easier. Same gasket I used too, helped get a solid seal against the block.

What's funny is I was laying under the Vette wishing I had studs for the oil pan. :lol:

Below is what I did instead, it wasn't the most straight-forward solution, but it got the job done.

"I'm using a one piece gasket, which is very prone to flopping out of place just when you get it to the block. So I used small zipties around the outside of the pan and one in the middle to hold the gasket in place. I made sure to put the ziptie on so the locking piece was out of the way. Once I got a few bolts started, I just snipped the zipties off and made sure the gasket was clear of debris."
 
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