I posted this in the exhaust category and got no replies, so I will try it here??
Does anyone out there know for sure whether it is better to use exhaust manifold gaskets or not on a 1990 302 V8?? Ford says this engine only requires gaskets when used in cars of this time frame and that the truck engines are designed for metal to metal. I have replaced the drivers side manifold and did not use a gasket, because of what the dealer told me and can't tell if it is leaking or not?? Is there a good way to check this?? Also, how do you keep the exhaust pipe/manifold joint from leaking? I have replaced the attachment bolts w/ new and have it tight as I can get it, but I still seem to have leaks??? I know you guys have the answers.

Thanks,
guzzler96

 

use a stethescope to tell if it is the manifold to head or pipe that is leaking.

 

A coworker once taught me a trick (it was on a chevy) that once you have everything tightened down, use a deadblow hammer and hit the exhaust around some, this will seat everything. I tried it, and it worked, took some wierd angles of hits and such but did work. As far as a leak, do you hear a noise when the truck is running, is there soot building up around the manifold??

 

I recently replaced the driver side manifold, because it was broken. I think what I am hearing may be more at the manifold/exhuast pipe joint at this point rather than at the manifold itself. Need a good trick/tip to get a good seal at this connection???

 

make sure it is lined up when you are tightening it down. i had a hell of a time with the headers on my last truck, had to use pry bars and such to get it to line up while i tightened it down.

 

$6 for the stethoscope dave186 recommended is way worth the money. I have a 92', 302 and use gaskets, had hell with the so called great copper gaskets, ended up with a cheap gasket and a little silicone and no leaks since. Thats with a header though, not a stock manifold. Just a thought, when I took my cracked manifolds off and replaced them with headers they had gaskets on them from the factory.

 

You guys go into a little more detail on the use of the Stethoscope. I have one and attempted to use it Saturday. Evidently I didn't know what I was supposed to do with it. Where do you listen? What am I listening for?? Can you actually hear air ?

 

It should have a little piece of hard metal tube stuck into the end of the hose, you just put the end of the tube against the joint where the manifold bolts to the head and slowly move it along and all the way around the manifold, a leak will be obvious when you cross over it, odd sound thats hard to explain. Hope that helps.
You could losen a couple bolts and create a leak so that you know what to listen for.

 

So I guess if you move the stethoscope around the manifold and the pipe joint and it all sounds the same, I probably don't have any leaks. If it all sounds the same and was leaking you could probably tell real easy. I guess your horsepower would probably suffer with a giant exhaust leak,NO???

Thanks,
guzzler96