exhaust manifolds

[pookster]

I got a '65 Mustang 200. I have an exhaust leak around the manifold so I replaced the exhaust manifold gasket, but I still have a leak in the same area. So I dont know what is up with that, any ideas? But my main question is if it turns out my manifold is cracked or something, can I go to a yard and pull an exhaust manifold off of any ford I6?
Mike

 

[mustang6]

Next time you remove the manifold, check it for cracks- cracks are usually pretty obvious on exhaust manifolds because the exhaust gases discolor the cracks. If there are no cracks, check the straightness of the manifold and head mating surface. It's most likely the manifold that is warped, but occasionally the head needs resurfacing too. Resurfacing the manifold is easy and cheap, resurfacing the head isn't all that expensive either but it involves removing it from the car.

 

[Anonymous]

I had a similar problem years ago and it turned out that the flange was out of round and it would never seal where the exhaust connects.

 

[Darren]

I spent the weekend dealing with a badly fractured exh. manifold. ('61 falcon w/ a 144). Was lucky enough to find a replacement at a local salvage yard, but still had a warped "exhaust inlet pipe flange" . The SOLUTION: permetex copper hi-heat gasket sealer. dope engine side of the "asbestos" flat gasket, let sit 10 or 15 min. then another bead on the (clean) face of the flange, let sit a few more min, then torque 'er down. THEN let it sit overnight. Drive. Smile.

At least that's what I did and other than the noisy tappets (I had to replace the head I broke also!) it seems to be holding up after a hundred or so miles. Good luck.

 

[CZLN6]

Howdy Mike and All:

The exhaust manifolds are all interchangeable, BUT: (Don't ya jsut hate big butts?)

1960 - '62 manifolds use a flat gasket to the head pipe, and hav a 1.75" outlet.

'63 and later manifolds use an asbestos donut and a fire wall seal to the head pipe and have a 2" outlet. '65 and later manifolds are cast significantly heavier, with gusseting is weak areas.

Beginning is '68 exhaust manifolds begin to sprout bungs for taps for emissions stuff. Later years got even worse. To the point where '80s manifolds have a design which has a fast burn cat converter attached directly to the manifold.

There has been talk about a larger/better 250 design. I have never (yet) seen one that is any different than the 200s for the same year.

My advice is to use a '65 to '68 exhaust manifold. Make sure there are no cracks or flaw, have it flat milled and use an exhaust manifold gasket to attach it.

Adios, David