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Putting together the 350 and have a concern about the torque specs for the pan bolts. Manual calls for 10 & 15 Ft-lbs for the 1/4" & 5/16" bolts respectively. However while tightening these bolts the cork Fel-Pro gaskets are becoming very compressed. Does everybody just tighten the bolts to spec? Photos show gasket after tightening less than 10 #s.
The only service manual I have handy is for my Wife's 84 Riviera and it shows 10 ft lbs for both the 307 and the 350 diesel. I have a Chevy service manual and it shows 80 in lbs for the 1/4" bolts and 135 in lbs for the 5/16 bolts.
The big question is what torque wrench are you using ?? I rarely use one on oil pan bolts but if i did it would be my 1'4" drive inch pound wrench. Most if not all 3/8" drive and bigger torque wrenches will not be correct at that low of a setting. Your gasket definitely looks squished out a bit
Just remembered that I had a problem a few years ago on a 425 with the oil pan leaking. It turned out that the rear rubber seal for the oil pan was made wrong and it was holding the pan off the block. I had to trim it to get it to seal. Make sure to check that.
Being an Olds V8, expect seepage no matter what. Honestly coat both sides of the gasket with RTV and a thin layer of RTV on both sides of the rubber end seals. You need RTV between the cork seals and rubber ends. I have tried pretty much every gasket, including the coated gaskets with the core, the felt like gaskets and the multiple cork gaskets. All seep some amount, just use everything you can to limit it.
"Rule of thumb" for torque wrench usage is: do not use the upper nor the lower 20 percent of the range scale of said torque wrench. 10 foot pounds (120 inch pounds) is pretty high for a 1/4" bolt. My 1967 CSM states 5/16" oil pan bolts 12 lbs/ft and 1/4" oil pan bolts 8 lbs/ft. Funny that the torque spec for the same 1/4" bolts when used on the valve covers is 7 lbs/ft!
There is a torque sequence for a pan, similar to the intake manifold. When torquing any large part, it must be done in steps, first snug all of them, then torque them down a little evenly, and then a final torque. Over torquing results in the gasket squishing out like what you show in your pictures.
Being an Olds V8, expect seepage no matter what. Honestly coat both sides of the gasket with RTV and a thin layer of RTV on both sides of the rubber end seals. You need RTV between the cork seals and rubber ends. I have tried pretty much every gasket, including the coated gaskets with the core, the felt like gaskets and the multiple cork gaskets. All seep some amount, just use everything you can to limit it.
what the heck are you doing? I have engines I built back in the 80’s that are still dry today….and every engine since then, still dry.
that’s using all available gaskets and sealants over the years …even no side rail gaskets , substituting Permatex Ultra black instead, dry dry dry.
I have done 4 Olds engines in the last three years including the 307 in my Wifes car and as far as I know none of them have leaked a drop. I know absolutely for sure that my garage floor is dry
The 425 leaked at first until I found the issue with the rubber end piece that I mentioned in my other reply.
[QUOTE=olds 307 and 403;1592137Honestly coat both sides of the gasket with RTV [/QUOTE]
I have seen guys do that on various engines and the gasket slides out because of the rtv
I have done 4 Olds engines in the last three years including the 307 in my Wifes car and as far as I know none of them have leaked a drop. I know absolutely for sure that my garage floor is dry
The 425 leaked at first until I found the issue with the rubber end piece that I mentioned in my other reply.
I have seen guys do that on various engines and the gasket slides out because of the rtv
It can move around, seen it on RTV and rubber intake end seals. I bought the fancy Canton pan, no better. He could try something like Aviation sealant as well, stickier. It is barely leaking, like my 4L80E barely seepage. About as good as an old automatic or Olds V8 can be.
So I took the pan off to check out the condition of the gasket. I had used Ultra black on both sides of the cork and there does not appear to be any slippage & the contact areas looked good for sealing. Bought the Mahle gasket set, OS30534TC, and was impressed with the thin metal sheet between the upper & lower layers of cork. Will put the Ultra black on both surfaces, add a drop of blue loctite to all the bolts & snug them down by hand. Comments? Felpro gasket after pan removed Side view of Mahle gasket showing 3 layers
So I took the pan off to check out the condition of the gasket. I had used Ultra black on both sides of the cork and there does not appear to be any slippage & the contact areas looked good for sealing.
When the rtv hanging into the pan breaks off and starts to clog oil passages, dont come crying about it
Originally Posted by 69355
Comments?
Yup . . . read the instructions that come with the gaskets. I bet there is no mention of smearing anything on the sealing surfaces No need for loctite either. It will keep you from being able to snug the gaskets up a little after a day. Thats what I always do.
I am sure by now you realize that I am not a big fan of rtv on most types of gaskets
If your crankcase ventilation system (PCV) system isn't up to snuff the pressure will push oil out no matter what also.
That and more pressure from worn out piston rings, causing more crankcase pressure and making it worse. I also have seen some minor seepage from the front timing cover seal and rubber/neoprene rear main as well, even after replacement. I also never really straightened the pan rails on 40 to 50 year old pans. I thought a brand new Canton pan, fresh rebuilt motor and the best gaskets available would completely seal. Pan was warped and the usual seepage occurred. It also has minor leakage on the drain plug, tried 3. I find old transmissions no different, always seepage at minimum somewhere, even after replacing seals and bushings. The speedometer housing is usually the worst along with some pans. Current 4L80E is the best so far, not a single seal replaced. Other than minor seepage at the pan and minor tail shaft leakage. I reused the rigid core with rubber sealing beads pan gasket and a brand new pan with a drain plug. But I used a mix of Dexron 3, regular and synthetic, 10W30 weight trans hydraulic fluid, Lucas additive and half a bottle of Blue Devil stop leak. I use the sequence if available, hand tight first and then to torque specs. Maybe gaskets don't like me and or I get defective parts. I used the 3M pads to clean, other times a razor blade, no different. Usually carb or brake cleaner to remove oil first. Either way the the literal couple of drops from seepage on my garage floor and very minor oiling is a part of old car ownership. Hopefully it seals 100%, pulling for you.
