Model A manifold on '29 pickup

D

Dkrahn

Member
Hope all is doing well.. I have a couple questions:
1. On the intake / exhaust manifold gasket, should you use gasket sealant or put on dry?
2. What is the purpose of the rings that go inside the ports? and are the necessary - I forgot to insert and wonder if I need to pull it back apart..

Appreciate your help
Dean
 
The rings help prevent the exhaust manifold from "drooping" over time due to heat. It's not a big deal, but if you have them and you didn't put sealant on the gasket, eh, I'd take it apart and put them in. You don't even have to take the manifold all the way off, just run the nuts out to the end of the studs and then pull the manifold out enough to get the rings in.

There are folks who use sealant and folks who don't. If you did use sealant, I'd recommend the copper spray. If your block is significantly pitted around the exhaust ports, sealing might be good insurance – or you can repair the pits using JB Weld ExtremeHeat paste.

Of note, a small number of early '29 engines were made without the counterbore required to use gland rings. If you have trouble getting them in, that might be why.
 
Later blocks and manifolds did not have the counterbores for the rings. If the manifold on your 29 has been replaced by one of the later manifolds then you don't have the counterbores for the rings. Same goes if you have a later engine. If your manifold has already sagged then the rings may not line up in all holes.

I put my manifolds on dry but both my block and manifolds are in good condition.
 
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nkaminar said:
Later blocks and manifolds did not have the counterbores for the rings.
Click to expand...

A common misconception based on a service bulletin in Jan. '29 stating that the counterbores were being discontinued. In fact they were only discontinued permanently for the intake ports. Counterbores for the exhaust ports were restarted in mid-March of '29 and continued through the end of production.
 
Thank you for the feedback. Since the previous manifold had the rings and I understand the use and value in them, I will pull the manifold back and slip the rings in. I did not use gasket sealant, so removal will be easier. I will continue with no sealant on the re-install.

Again Thank you
 
I used the copper 2 piece gaskets. The gasket bends / stretched where the studs are. Concern if leaking there.. Does it matter which way the gasket goes on? I put the side that shows the rings toward the manifold.
 
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Dkrahn said:
I used the copper 2 piece gaskets. The gasket bends / stretched where the studs are. Concern if leaking there.. Does it matter which way the gasket goes on? I put the side that shows the rings toward the manifold.
Click to expand...

It doesn't really matter, but for copper crush gaskets like those the consensus is to put the ring side toward the manifold so the impression will be on a part you can easily take off and have resurfaced.
 
Ok i did that..wth them bending in where the studs are, can I assume that is normal? Nothing to worry about?
 
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I got tired of pulling them out of the muffler, and haven’t used them in years!
BTW a new manifold isn’t that expensive. If you want to protect your manifold, I’d be more worried that the tailpipe hanger was a loose fit, per design. I actually cracked a new manifold because the muffler was dropped in front while I was messing with the glands, and it bent the rear hanger. Shortly afterwords it cracked the manifold just to the front of the rear bend the muffler bolts to. It’s amazing how much the muffler expands in length with heat.
 
A gland ring seal keeps the pressure from trying to exit around the circumference of the flange by adding a wall barrier there. It also smooths the flow of gasses out of the block as long as the ring is a flush fit with the ID of the ports at the edges of the ring. Without the gland ring, it wouldn't take as long to form a leak on the flange gasket. The rings do have to fit well and some are better than others. Some 1929 blocks may not have the counter bores to fit them.
 
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