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Hi All, rehashing an old topic.....

Got the engine all put together, tuned, and took it out for a test drive 2 days ago. Everything went smooth.

Today I try and start 'er up and have a *BIG* exhaust manifold leak at the block. Must also be a intake leak because I also have a severe loping idle.

Upon visual inspection, the new manifold gaskets I installed from MM have "baconed" really badly. They have really distorted. The material of these gaskets seems to be some black synthetic material. The old Gaskets I took off had a foil on the manifold side. I read in another thread that someone is making the foil type, but no contact info is given. Anyone know where I can get better gaskets?

Thanks
-Dave

Hi Dave,

I imagine a big reason the gaskets failed to seal is warped manifolds. That would have to be corrected for any gasket to work correctly. Secondly, I too prefer the metal clad gaskets. I bought mine from Packards International. Here is the contact information found on their website:

Office:

Lani Brizic
Packards International Motor Car Club
302 French Street
Santa Ana, CA 92701

Phone: (714) 541-8431
Fax: (714) 836-4014

Best of luck,
Jim

When the manifold(s) were installed did u loosen the bolts that hold the intake manifold to the exhaust manifold and then tighten those AFTER the the manifolds were torqued to the block?????

Yup. I followed the procedure outlined in the manual.
Did the straight-edge/feeler gauge check before installing as well. I guess I'll check it again and take it to the machine shop to have it milled...

Though I and others prefer the metal sandwich manifold gaskets, the composite type give good service as well when properly installed; your problem is not with the gasket construction type. Don't forget the manifolds have to "float" a bit with expansion and contraction so the torque specs for tightening them is important.

I'd suggest having the manifold mounting surfaces planed or surface-ground as a unit assembly.

First thing i would do is try to first CHECK the existong torque. See if any has loosened. Retorque the manifold and hope for the best. At this point there is nothing to loose by trying a retorque. If it doesn;t work then or if a gasket has a hole blown thru it then procede as instructed in the above posts by others.

I had this same issue, no exhaust leak but it was fine then loosing power on the freeway then wouldn't idle or barely go unless you pumped the gas.

I chased everything around until i re-tightened the manifolds and now it will idle, but roughly under 800 rpm, but it does run by itself at 450. Idle screws are adjusted pretty far out, but not too far. I'm guessing the same happened to me.

I did notice that when i went to tighten them, they were pretty damn loose, not near what i torqued them at. I did do the correct procedure...i had them apart to sandblast, paint, and new gaskets, tightened to block first. I'm thinking that after i got the car back together, that the heating and cooling of all my tuning and couple test drives caused the manifolds to "settle" and if i had torqued them before it started running rough, maybe it would still be fine. I just tightened them "damn hand tight" in my haste and that got me back to somewhat running. Maybe i'll revisit putting new gaskets on there and checking the manifolds with a straight edge.

One note, between the rear-most gap between the intake and exhaust, i saw my gasket had heaved around the stud. I thought i had found the issue, until i saw my old engine, that ran great, had the same issue. Old motor seemed to have metal gaskets, new were like cardboard with metal in the middle. Both scrunched up in the same spot, but don't seem to affect:

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I have had similar problems with the gaskets that are the same on both sides with a metal core. Of corse the correct torque is very important as well as to re-torque after the engine has been warmed up and run a wile. Also checking the manifold for flatness and re-surfacing if needed is important.

The best gaskets are the ones that are metal on one side and gasket material on the other. The problem here is that the intake/exhaust manifold is very long and expands and contracts every time you drive the car by quite a bit. The manifold scrubs back and forth and wears into the gasket destroying the gasket thus causing leaks. The gasket with the metal on one side provides a surface That can take the constant rubbing without deforming. The metal goes towards the manifold.

Bottom line is I don't use the gaskets unless they are of the type that has metal on one side.

surfacing

Are the metal on one sidew the ones that are available from the packard club international? If not, where can i obtain that type?

Yes, those are the ones available from PI. There are a club project of the So Cal region of PI.