Removing the exhaust and intake manifold

Tom Cavallaro

Tom Cavallaro

Senior Member
Tried to tighen the manifold up and run it...no avail. Still leaked. removed everything and found 2 gaskets...why? I don't think it should be necessary, but asking for opinions. Tomorrow I will take the manifolds and glass bead them and then take it to Napa down the street and have them check it out and sand them flat if necessary. Doesn't seem to have a droop as suggested earlier. Just wasn't expecting to find two gaskets.
 
Hello Tom:
There shouldn't be two gaskets as you suspected.
Clearly the manifold is warped. I would have the resurface it and then get the copper style exhaust gaskets"the good ones" rather than the asbestos sheet.
 
Tom, sanding probably isn't going to do it. Have them machined together so you've got one flat continuous surface, then install them with the gasket J&M suggested. Make sure your washers are installed in the right direction. Snug the nuts down to about 40 lbs, then snug 'em again after you've warmed it up. Some say torque 'em to 55 lbs, but I've always just tightened them 'tll they're tight.
 
Tom,

Check the studs for damaged threads ... many times folks use pipe wrenches or visegripes to tighten or loosen the studs. Or studs are all rusty and dirty. Many such things have happened over the last 80 years.

In the process they damage the threads. Then the nuts jam on the studs and donot tighten the manifolds as they should. The nuts appear to be tight but do not clamp the manifolds tightly to the block.

Sometimes the holes for the studs in block are full of rust and dirt so the studs are too long and the nuts run past the threads where they bind up.

Any of the above might be the reason for using two gaskets.

Checking the height of the six ports with the two manifolds bolted together and truing them as stated above is the first step.
 
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700rpm said:
Tom, sanding probably isn't going to do it. Have them machined together so you've got one flat continuous surface, then install them with the gasket J&M suggested. Make sure your washers are installed in the right direction. Snug the nuts down to about 40 lbs, then snug 'em again after you've warmed it up. Some say torque 'em to 55 lbs, but I've always just tightened them 'tll they're tight.
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Good advice. The intake and exhaust need to be machined or plained together as one unit.

A gasket will make up some problems. But the advent of extra gaskets says to me they installed knowing it was not true.

Till they're tight.

my experience.
http://fordbarn.com/forum/showthread.php?t=11433
 
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Tom Cavallaro said:
Tried to tighen the manifold up and run it...no avail. Still leaked. removed everything and found 2 gaskets...why? I don't think it should be necessary, but asking for opinions. Tomorrow I will take the manifolds and glass bead them and then take it to Napa down the street and have them check it out and sand them flat if necessary. Doesn't seem to have a droop as suggested earlier. Just wasn't expecting to find two gaskets.
Click to expand...

It depends on what you mean by two gaskets. If it is gaskets stacked on top of each other, that would indicate a problem like Clem mentions. Otherwise model A's originally came with two gaskets. One gasket for the front three ports and another for the rear three ports. You can lay a straight edge long ways across the manifold ports and see for yourself if the manifold is warped. Laying a straight edge under the bottom of the manifold ports longways will help detect a sag. The manifold isn't under compression like a cylinder head and doesn't need to be torqued. I just tighten the manifold nuts reasonably tight working from the center outward. I have had the best luck using the two piece late 31 style gaskets, because they are wider and cover more area, this is helpfull if there is a slight sag and gives a better chance of a good seal. There is a cheap one piece gasket that is steel clad on one side only, this is the only one piece gasket that is listed in the catalogs that I do business with. I would avoid the one piece steel clad on one side gasket.
 
Since we are talking manifolds, what do you paint or cover the manifolds with to keep them looking good. I plan to install Red's tubular headers soon and don't want them looking old too soon.
 
do everything people have mentioned above, but i would suggest not torquing over 35 pounds. If they're machined together you don't need to torque them anymore. I used 25 pounds on my coupe for two years without a leak, and i torqued the one on our fordoor to 35 but i wouldn't go anymore, it was really tight for those little manifold ears.

Just my opinion
 
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