how can you tell which pan gasket a 350 sbc takes...I understand there is a thick and a thin one and would like to replace my gasket but want to get one before I pull pan...The leak may in fact be coming from the wrong gasket in the first place.
https://www.summitracing.com/parts/sum-g2330/overview/make/chevrolet or https://www.summitracing.com/parts/mil-41000/overview/make/chevrolet
Original GM pan will take a different gasket than say an aftermarket aluminum pan... as previous mentioned dipstick location, pre or post '86 for rear main seal type. Couple things to identify about your engine will narrow it down.
If memory serves me correctly, I believe the difference in Small Block Chevrolet pan gaskets comes from a different size front seal used in the timing cover. There was a thick or thin seal depending on which cover you had. I’m referring to the “U” shaped piece at the front of the gasket, not the harmonic damper seal. I kinda think the early covers used a thin seal and late ones were thicker. Sent from my iPhone using The H.A.M.B. mobile app
Also, read this thread....https://www.jalopyjournal.com/forum/threads/which-oil-pan-gasket-for-my-sbc-engine.783567/
http://www.speedwaymotors.com/Tech/seals-thick-vs-thin-oil-pan-gasket.html Quick Tips to Know Ever ran into the headache of an oil pan gasket that doesn’t quite fit your timing cover? Well, like every problem, we have a solution; or a tip rather, that will save you the extra run to the parts house. On a small block Chevy engine, some oil pan gaskets are a bit thicker than others (about 1/8-inch) and this can cause a problem where the gasket seals inside the timing cover grove. Some timing covers (like Speedway's 910-11040) have a thin grove, and others are thick. Fel-pro specifies a thick gasket at 3/8-inch, and a thin gasket at 1/4-inch. The images on the right compare the problem found between a thick and thin gasket. Photo A In this photo we installed Speedway’s billet timing cover onto a small block Chevy 350, which is intended for a thin-style oil pan gasket. Notice the width of the groove where the oil pan gasket should seat inside of. Photo B In this photo we installed a one-piece gasket similar to Superseal’s 910-10223, which is intended for a thick-style timing cover. Photo C If you look closely, the gasket is too thick to fit down inside the timing cover groove, which won’t allow the oil pan to bolt up. Trying to bolt the oil pan on could damage the gasket and cause leaks. Photo D In this photo we installed Fel-pro’s premium three-piece gasket that is intended for a thin-style timing cover. You can see how the front seal fits down inside the timing cover grove perfectly. Photo E Notice the difference between this photo and photo C, the oil pan will now bolt-on and properly seal. Aftermarket and factory timing covers can vary, so it is best to measure your timing cover width before buying a replacement oil pan gasket. FelPro One Piece Oil Pan 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 Sent from my iPad using The H.A.M.B. mobile app
Yes, the OP need to verify exactly what he is working, stock timing cover/aftermarket etc. We can't assume he has a stock stamped tin timing cover.
2piece rear seal and dipstick on driver side stock timing cover and pan Sent from my iPhone using H.A.M.B.
Yep, bought a bunch of one piece gaskets...I had mis read the description from fel pro.... Sent from my SM-J320V using The H.A.M.B. mobile app
trying to get more info on this engine the casting code confirms its a 350....but the pad where the vin code is stamped is blank, never been stamped...possible crate motor?
Deck probably has been surfaced. Dipstick on drivers or pass side? Stock stamped steel oil pan and timing cover?
new question...i assume the front crank seal installs from the outside of the timing cover, so can be changed without pulling timing cover....reason I ask...went to several parts houses (napa, smith...etc) and only way to get the seal is to buy a timing cover gasket set....makes me wonder if the seal has to install from inside of cover.
So the original question.... How do you tell if the engine uses the thick or the thin gasket at the front where the timing cover meets the oil pan.... Year of engine really is only a guide. All timing covers are the same size. The difference is the opening or mouth at the front of the pan. I've seen the later , large opening pan used on small journal early engines.. You can tell what is needed by looking close at the pan / cover area. If the pan looks like its touching the timing cover it takes the thin gasket. If the pan sits about 1/4" away from the cover it takes the thick gasket. Also almost all aftermarket pans use the thick gasket. Hope this helps.. Btw.. the actual timing cover seal installs from the outside of the timing cover.. The part # for just the seal is # 9845.( national or timkin brand ) Local parts store should be able to cross that # to whatever brand they carry. I'm a retired old school parts guy.. Dave Sent from my SM-G973U using The H.A.M.B. mobile app
thanks Dave...I have a bit of an oil leak that I thought was coming from the rear main seal, but yesterday I went underneath to look closer and it looks like its actually coming from the front of the motor...not a bad leak but enough that I want to correct it...pulled the pan down and it has one of the blue rubber neoprene one piece gaskets. I looked it over very close and there was no oil on the mating surfaces of this gasket and the area that seals the bottom of the timing cover looks to be compressed enough to seal so Im thinking it could be coming from the front crank seal. I finally found a Timkin seal and will get it changed out in the morning....if this dont stop it I will go ahead and replace the pan gasket with new one...still relearning the SBC....spent a lifetime with Fords and Mopars with just a scant few Chevies mixed in, so didnt realize there were many changes throughout the years...makes it a little confusing....thanks for the help guys. thanks for the tip on the gap between pan and cover...im headed out to check this right now.
Many people say the FelPro one piece gasket worked good for them, wish the brand new $29 one that we put on my roadster engine had not leaked, didn't even make it through the dyno session, man it was hard throwing it in the garbage.
Ron, this is the only engine I've ever had professionally assembled, he told me he just put a stock replacement four piece set on it, more than likely was a FelPro also.
Well....found the problem. Went out this morning to change the front crank seal and noticed the leak was actually at the front of the pan/timing cover area. I could actually move the gasket around by pushing on it. Pulled the pan down and it has the thin type Felpro 1 piece blue neoprene gasket. Pulled a new one at the parts house and the thick one is WAY to thick to fit. So I bought a new Felpro 1 piece gasket and a tube of Permatex gasket maker. put an 1/8" thick layer on both sides of the gasket at the timing cover area and reinstalled the pan...will let it sit overnight and try it tomorrow. If this dont fix it , though its a brand new stamped steel pan, I will buy a new pan or even a cast aluminum pan if needed. Hopefully the gasket maker will do the trick....has anyone tried shimming the gasket at this area? maybe 1/16" X 1/4" by the length piece of neoprene in this area and maybe adhering it to the gasket to make a tighter fit? looks like this has been a problem area for others in the past....just thinking
FWIW , I'm sure you need the thick front seal 1 piece pan gasket , I buy the cheap ones from competition products. When you install it , it seems too thick , its not . I use longer 5/16" bolts to draw the pan into position , until I can start the 1/4" perimeter bolts , then change the 4-5/16" bolts to the appropriate length. A tiny bit of silicone in the 4 corners is all that's needed . The gasket on my engine now is 8 years old and has been re- used 3 times . No leaks ! Dave
Ya know, my '89 block has a factory 1 piece gasket. I like FelPro/etc. but I'll mosey of to the pars counter at my local GM, pay way too much for it and not worry about a leak. I'm getting too old to do things twice. Edit: I hate using sealer. I only use it for the china walls on a SBC, no gasket.
unfortunately I dont know the year of my engine...the serial numbers were apparently machined off when it was decked...the casting numbers show it to be a 350 but no way to know the year
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