Inliners International Forums General Discussion Engines chevy 250 valve cover torque specs

Can someone tell me the valve cover torque specs on a chevy 250?

So I found out that you just need to tighten the bolts hand tighten. The problem is that my valve cover still leaks oil from both sides even with a new gasket and cover. I'm lost as to why is leaking. I used both cork and rubber gaskets and no luck.

Your gasket surface on the cover is probably bent and not allowing it to seal good. Take it off and set the gasket surface down(without gasket attached) on a piece of glass and see if it rocks side to side because its unlevel. You can straighten the surface back out with a small hammer laying the cover surface against a block of wood.

The valve cover is brand new. And we make sure it was all flat. I just don't understand why is not sealing. I don't want to torque it down more and cause the cover to warp.

Ok, you didn't say what cover it was. But it can still be warped, that's the only thing that can make it leak. Place it on a flat surface and check it anyway.

Sometimes the flange areas on the cover immediately around the bolt holes need to be peened away from the sealing surface. This more evenly spreads out the clamping force in the areas between the bolts when the bolts are tightened for a better seal.

Put a straight edge on the head. I work on a lot of heads. The gasket sealing surface is "as cast" and many times is not a straight sealing surface. If this is the case, 2 gaskets stacked can help with the seal. The head can also be machined flat in extreme cases.

Ok sounds like I will be taking the cover back off once again and this time I'm going to go with double gaskets just in case. Will post results.

An old hotrodder told me a long time ago that if you just kinda snug the bolts up a little while cold, then run the engine up to operating temp (or even a little hotter with the help of a piece of cardboard in front of the radiator), shut it down and tighten up the bolts-torque spec or whatever way you choose-as the engine cools it will suck the valve cover down even tighter. Once it's completely cool, re-torque the bolts again and it will never leak again. I don't know if it helps or not, but it's what I do and never seem to have any issues with leaky covers.

There is no "sucking down tighter as it cools down". The engine is not able to hold the theoretical vacuum that would result from cooling of the internal gasses and fluids. It is not a sealed system. So that part of the ole wives' tale is BS.

And don't let the engine overheat for any reason.

I would recommend a new gasket, check the surfaces for straightness and flatness, and use blue Hylomar or equivalent sealant on both sides. It won't harden, and it can tolerate oil and even gasoline. it just gets tacky.

Hammer the edges of the bolt holes flat, they collapse and cave in with use, especially if retainers are not used to dissipate the load: http://rcmotorcars.com/cart/images/2427%20valve%20cover%20reinf.jpg

Pritch/nova, thank you for your advice. I'm planning on getting a new gasket and starting again. I will make sure the hole surface areas are nice and flat. I do have retainers for the bolts.

45 INCH POUNDS start in middle work to out sides alternating side to side.

Thank you.

Psssstt:

http://www.jegs.com/i/Spectre/865/5321/1...CFbTm7Aod_UsATA


these spread the bolt tension further out, almost like a spring adding 2 more pressure points. No personal experience.

I have some already but they're shorter. Thanks