Exhaust manifold glands
 

All, good day.

On the Model A engine, there are metal glands that insert into the exhaust manifold and also into the exhaust ports on the engine block. When installed these glands keep the manifold exactly aligned with the ports. The width of the glands somehow relates to the depth of the recesses in the manifold and block, plus an allowance for the gasket thickness.

What I'm after is the relationship between the width of the glands and the depth of the recesses. I need to deck my manifold assembly to get it flat (and get rid of leaks), and I realize that I need to decrease the width of the glands appropriately. But how much? If I had an unmodified engine I would simply reduce the width of the glands by the amount the manifold decking removed, but my engine has been rebuilt and I presume that the manifold mounting surface was decked at that time. And I'm not sure that the present width of the glands is proper. So my "original" manifold+block combined depth is lost forever.

Should the glands allow the manifold to sit flush without the gasket, so that when the gasket it installed the gasket is allowed to crush? Or should some allowance be provided for gasket thickness (say, half of the uncrushed thickness??)

Or, does anyone know the original depth of the block recesses? I can measure what I have and deal accordingly.

Thanks, all.

JayJay

Re: Exhaust manifold glands
 

Do the machine work first and then measure. Some find cutting their own rings from steel pipe works better than the rings you can get nowadays as they would be solid round. Personally I would test fit without the gasket.

Re: Exhaust manifold glands
 

When I brought my new Aries SS muffler, I didn't use the gland rings on the manifold. My thinking being that one or more will eventually end up inside the muffler. If you keep the manifold torqued to 45 foot pounds, you won't have to wrong about manifold sag.

Re: Exhaust manifold glands
 

If they are installed properly they shouldn't migrate. The ones made of actual pipe would be more secure anyway. Ford wouldn't have spent the money to add them if they were unnecessary. They are used to keep hot exhaust gasses off the gasket.

Re: Exhaust manifold glands
 

I agree,

I use them an all the engines I am involved with. They help support the manifold and keep the hot exhaust gasses from the gasket.

In the middle of the Model A production for a sort time, Ford did away with them only to re-instate after they confirmed they were necessary.

Chris W.

Re: Exhaust manifold glands
 

The way I did it was to seat the rings one by one in both the block and the manifold, and then use calipers to measure the amount of ring protruding from the surface at the highest point for each (because on the block side it's unlikely the rings will seat perfectly flat).

You write it all down and then you pair up the numbers for each exhaust port on the block and the manifold. If the exposed ring width on cylinder #1 block-side plus #1 manifold-side is less than or equal to the total width of the ring, then you have sufficient clearance on that cylinder. If it's barely greater than, you should assess the expected width of the compressed gasket and make the call.

Side note, Remflex makes exhaust manifold gaskets that are extra-puffy, which helps with sealing and gives a bit of additional clearance, if you don't mind the non-copper look.

Re: Exhaust manifold glands
 

Measure once and cut twice, or is it the other way around?

Re: Exhaust manifold glands
 

Measure as many times as you like, I didn't think I had to spell it out in detail.

Re: Exhaust manifold glands
 

He was making a joke, having a bit of fun.

Re: Exhaust manifold glands
 

I like the split rings so that I can expand them to provide a spring fit to keep them in place while I put the manifold on. I have never had one go south to the muffler.

Measure with the gasket off to provide a little clearance for the rings.

Re: Exhaust manifold glands
 

I don’t use them anymore. I also don’t have a manifold gasket leak problem. So I think it’s a waste of time. IMO

Re: Exhaust manifold glands
 

I think why most people claim they go into the muffler is people install them wrong and or use them on warped original manifolds. I have never had trouble with them.

Re: Exhaust manifold glands
 

Reminds me of the old adage "You can lead a horse to water but you can not make him drink"

Re: Exhaust manifold glands
 

I’ve used the gland rings on all the Model A’s I;ve owned, as they keep the manifold aligned to the block. Never had an issue with one getting into the muffler.

When I recently replaced the exhaust manifold with a new one from Brattons, I had both manifolds milled flat and measured and adjusted each gland ring with my bench grinder. Easy and quick to do.

Jim

Re: Exhaust manifold glands
 

Folks, this has been a great discussion, thanks a million for all your input.

Jim (Conaway2): when you "measured and adjusted...", what measurement did you use as your basis of adjustment? From Alexiskai's comment, I'm thinking that the "correct" width of the gland ring is the combined depths of the block and manifold recesses, and figure that after installation there will be a bit of a gap at the ends of the gland rings due to the thickness of the gasket. This seems reasonable to me. Does that sound correct?

JayJay

Re: Exhaust manifold glands
 

JayJay - I initially measured the combined depth of the block and manifold cutouts and gasket thickness with my dial caliper, then began grinding and test fitting each ring. I used the flat side of the grinding wheel at pretty low speed. I needed to take less than 1/16th” off each gland ring. I also knew that the machine shop had removed less than 1/16” from the combined new exhaust/original manifolds bolted together.


Everything lined up quite well, so installation of the gland rings was easy - unlike trying to use an original exhaust manifold.

I’ve tried to use several original exhaust manifolds in the past three years and all were warped enough that they would not align with the exhaust ports in the block. The new exhaust manifolds from Brattons - and probably other vendors - are well-made and fit very nicely. They’re not identical to original ones, so probably not for a fine-point car.

Good luck - Jim

Re: Exhaust manifold glands
 

Thanks, Jim. Indeed, after looking at the manifold after I got it off (old, pitted, crusty, the muffler sealing surface was way pitted), I decided to bite the bullet and get a new one. (Intake manifold is fine, did the requisite breaking off of the bolts holding them together, cleaned it up and the paint is drying as we speak.) Bratton's actually has a fact sheet on fitting the gland rings - I guess I could have avoided this whole thread if I'd just done more research first. But I learned a lot.

Thanks for your help.

JayJay

Re: Exhaust manifold glands
 

Hello Gentlemen,

You have a good discussion going on here and the answer to one of my questions is answered where you talk about making the gland rings shorter to fit the combined depth of each engine block exhaust port recess and corresponding manifold port recess and then allowing for gasket squishing or compression.

I am lucky because all of the ports are aligned very well in my '30 Closed Cab Pickup with original parts.

The other question that I have is how much does a copper gasket compress in thousanths of an inch?

Thanks
Elmo P Quackenbush

Re: Exhaust manifold glands
 

The gasket manufacturer will have that info, you should be able to call/email and ask.

Re: Exhaust manifold glands
 

I would not torque exhast manifold more than 30 lbs, IMHO