351W manifold to down pipe, is there a gasket?

[Ash]

Guys, I need some advice to whether there should be a gasket on my 1990 351W EFI F150 motor where the exhaust manifold flange meets the down pipes on both sides. I have an exhaust leak here, you can see it blowing out the side. I got some gaskets some time back but there were none in there when I undid the pipe and am not sure if they are meant to have any?



These are the gaskets I was given. Are they correct? If not, what if anything goes in there? And if in fact there should be nothing, how do I stop the leak?

[peter9231]

Hello,
They don't have a gasket, tension and carbon seal design.
Looking at the pipe it appears a bit distorted.
Looking at the witness mark on the manifold it looks like it has been misaligned.
Hope this helps.
Peter.

[Ash]

Thanks for the reply, Peter.

Would I be right in saying that by misaligned it is angled too far to the right of the photo?

The side shown is the right. After the pipes go down and angle back, both sides are then joined together then about a foot later they join again at the flange that bolts to the cat. I don't think I'm going to have a lot of give in shuffling one side.

The system is pretty old. Should I perhaps just do what I can to align as much as possible then look at another system to replace it?

[Ash]

Got it sorted. I fitted the tightest, right side, first so it was snug then fitted the left. Leaks are now gone.  Also swapped out the O2 sensor while I was under there.
Along with a new set of plugs, air cleaner and MSD leads, it now runs the smoothest it ever has. Just waiting on a new MSD cap and rotor to turn up as well

But now as usual, as well as my dodgy hearing not helping, you fix one problem and find another. Now that the exhaust noise is gone, I can now hear a ticking lifter.

Thanks again for the reply, Peter 

[peter9231]

Ash,
Good job, glad you have solved the problem.
Peter.