The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Exhaust Manifold Warped

I have a '66 250 6 cyl. I had a guy tell me after looking at my exhaust manifold that it was warped and therefor leaking. The engine has 4200 miles on it and previously the manifold seated properly. There are no visible cracks - yet it is leaking where the mainfold attaches to the block. The bolts don't appear to be loose. Why would the mainifold warp? Can it be resurfaced - or should I buy new? Tim-o

I would hahazard a guess, that IF the warp ain't too bad a double layer of gasket might do the trick, Getting it magnafluxed would be the best way to tell if there are cracks.

That is a strange one.

You should be able to take them to the local machine shop and get them resurfaced.

Thanks for your input. I, too, think that it is a little strange that the manifold would seat for 4000+ miles then develop a leak. I envision taking the carb off, disconnecting the exhaust pipe and removing the intake and exhaust manifold as one unit. My thought then is to place them on the workbench and use a straight edge (like a level) to see if the surfaces are too uneven to be spanned by one or two layers of gasket. I have seen on other posts advice of using grease - or gasket adhesives - do you have a preference? If they are out of alignment too much - I'll take them to a shop for leveling. Sound like a plan? Tim-o

When the intake & exhaust are mated together, they should be laying on a true-flat surface, before bolting them together and affixing them to the head. Regardless, they mating surfaces of the intake & exhaust manifolds, need to mount flat to the head. Instead of running the risk of the double gasket or sealer working, the intake/exhaust manifold assembly will be off the engine, so having it surface, is the best approach, imho.

Good thoughts. Thanks for the input. If there are no cracks, does it make any sense to separate them? Next weekend I'll tear it down and see what I have. Stay tuned!!

Use two gaskets as Modelman suggested. I had a 230 in a '70 Nova, and the two gasket trick worked great!

We have an engine builder near here that has a huge belt sander, he ran my 230 manifold over the sander for about a minute and it was great. But don't forget, if you have a fresh engine most likely you didn't re-torque your manifold at about 500 miles, just try a new gasket and re-toque every couple hundred miles until the nuts don't move anymore. Also check oil pan and side cover bolts. I make a bolt check on the whole engine every spring when I get the truck out, there are always a couple a little loose.

Two gaskets work great, until two gaskets don't work great anymore and then it has to come off and be surfaced. With the intake/exhaust manifold off the motor, in order to install two gaskets, it would be a good opportunity to have it surfaced.

63burban - I did retorque the pan and side covers. But not the exhaust manifold. Never crossed my mind! Until now. A friend suggested I try retorquing the manifold before taking it off. Might give it a try. I did pick up the gaskets today and PB blasted the bolts last night. I'll let you all know how I come out. Thanks for all the good advice! Tim-o

63burban - I did retorque the pan and side covers - but not the manifold. Dang! I picked up the gaskets today and PB blasted the bolts last night. A friend at work suggested I try torquing the bolts first to see if that works. I guess it is worth a try. I appreciate all the advice. Star tuned! Tim-o