Big block rear main seal
Thread Starter
Safety Car
Joined: Sep 2005
Posts: 4,226
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From: Orange County Ca
Big block rear main seal
I'm going to change my 69 477 oil pan gasket and rear main seal.
I've searched the forums and mostly see threads for small blocks, which I assume are simular. There seems to be different widths of seals.
Does anyone know the brand and part # of the best 2 piece seal?
Also, there seems to be disagreement as to what sealant to use on the main cap. Some say to use rtv and others say not to use rtv, but to use gasket sealant. Some of the threads are old, so what is recemended now?
Thanks in advance.
I've searched the forums and mostly see threads for small blocks, which I assume are simular. There seems to be different widths of seals.
Does anyone know the brand and part # of the best 2 piece seal?
Also, there seems to be disagreement as to what sealant to use on the main cap. Some say to use rtv and others say not to use rtv, but to use gasket sealant. Some of the threads are old, so what is recemended now?
Thanks in advance.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
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I just use normal Fel Pro seals. There is a "Hi Perf" version made from better material..one is brown..the other is blue. Either will work great for what you're doing.
I usually "offset" the two halves so the parting line isn't directly in line with the block/cap juncture.
I don't use anything under the cap...just metal on metal...but I know some that do. If you are going to put something in there, don't use silicone, use a sealer like Permatex Aviation sealer or similar...and only a thin coat.
Silicone and other excess sealers are not something you want coming loose and floating around in your motor.
I like the one piece pan gaskets, but BBC's work very well with the multi-piece ones too.
On the one piece, use only a small dab of sealer at the four corners by the cap and timing cover. Leave the rest dry. On the multi-piece I use the Permatex Aviation sealer.
Whatever silicone you use on the pan or say on the intake manifold end rails, make sure it is good for oils. Read the tube. Many don't like oil at all. The Permatex Ultra is good. If you really want to make sure...use the "Right Stuff" line of sealant. You have to be careful..'cause it won't come apart as easily later..but it doesn't leak.
JIM
I usually "offset" the two halves so the parting line isn't directly in line with the block/cap juncture.
I don't use anything under the cap...just metal on metal...but I know some that do. If you are going to put something in there, don't use silicone, use a sealer like Permatex Aviation sealer or similar...and only a thin coat.
Silicone and other excess sealers are not something you want coming loose and floating around in your motor.
I like the one piece pan gaskets, but BBC's work very well with the multi-piece ones too.
On the one piece, use only a small dab of sealer at the four corners by the cap and timing cover. Leave the rest dry. On the multi-piece I use the Permatex Aviation sealer.
Whatever silicone you use on the pan or say on the intake manifold end rails, make sure it is good for oils. Read the tube. Many don't like oil at all. The Permatex Ultra is good. If you really want to make sure...use the "Right Stuff" line of sealant. You have to be careful..'cause it won't come apart as easily later..but it doesn't leak.
JIM
Thread Starter
Safety Car
Joined: Sep 2005
Posts: 4,226
Likes: 643
From: Orange County Ca
[QUOTE=427Hotrod;1585820725]I just use normal Fel Pro seals. There is a "Hi Perf" version made from better material..one is brown..the other is blue. Either will work great for what you're doing.
Thanks Jim.
Yes, I also like to go with well established brands.
The "high dollar" rear seal at Rockauto is a National brand, nitrile material. National is a FederalMogal brand. Any ideas about this seal?
Definately will go with the FelPro 1 piece pan gasket.
Thanks Jim.
Yes, I also like to go with well established brands.
The "high dollar" rear seal at Rockauto is a National brand, nitrile material. National is a FederalMogal brand. Any ideas about this seal?
Definately will go with the FelPro 1 piece pan gasket.
Drifting
Joined: Jul 2011
Posts: 1,697
Likes: 139
From: Syracuse NY
Realisticly, how much of a PITA is this job (with the engine still in the car)? Im contemplating doing my rear main but I dont want to make matters worse. I dont mind the oil leak, but Im afraid of eventually saturating my clutch plate. The car is on jackstands and currently undergoing a cam swap, so nows the time (if I decide to do it)
Race Director
Joined: Sep 1999
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From: Plano TX
It's not a big deal to replace it. You have to drop the steering linkage to get the oil pan off, that's probably the biggest part. Unbolt the PS ram, pop the steering link off the pitman & idler and let it hang down. Much easier than a cam swap!
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
2017 C2 of Year Finalist
Realisticly, how much of a PITA is this job (with the engine still in the car)? Im contemplating doing my rear main but I dont want to make matters worse. I dont mind the oil leak, but Im afraid of eventually saturating my clutch plate. The car is on jackstands and currently undergoing a cam swap, so nows the time (if I decide to do it)
A Vette is about the easiest car on earth to pull an oil pan. Not much of anything in the way.
The Federal/Mogul seal would be Ok too. I wouldn't be scared of it.
I usually buy the Fel-Pro R.A.C.E sets for the small stuff and then buy the pan gasket, valve cover gaskets, intake gaskets and head gaskets separately that I need for each particular build.
JIM
Thread Starter
Safety Car
Joined: Sep 2005
Posts: 4,226
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From: Orange County Ca
Thanks all.
I'm contemplating 5/6 hrs, so it will probably take 25. HaHa.
I'm going to buy the more expensive parts and hope that they may be a little better quality because I don't want to do this again. Standard parts would probably be just fine, but the few dollars difference is worth it for me.
I'm contemplating 5/6 hrs, so it will probably take 25. HaHa.
I'm going to buy the more expensive parts and hope that they may be a little better quality because I don't want to do this again. Standard parts would probably be just fine, but the few dollars difference is worth it for me.
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