Two part heads

Gary-UK

Senior Member
Anyone in fordbarn land ever run two part cylinder heads? I think the only ones ever made were Roof and Norm Frick?

I have a pair (Roof) on a fresh engine that I have just run up for the first time and have a couple of leaks around the plugs on each side. 3 on one side 2 on the other.

My first thought is to take the easy route and stick some ceramic block sealer in there to stop the leaks, another part of me says tear it down and reseal them. The question is what to use as a gasket material? At the moment there is a thin black sheet material of unknown origin as they came with the heads, I coated both sides of this thinly with aviation permatex so if I split them this material is going to have to be replaced.

Any suggestions on a material I can get in sheet form, that can be cut to shape by knife and will work and withstand the torque of the head studs?

Thanks....
 
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I have some pictures of them with the top cover off which I can post up later. I am thinking of trying a thin gasket paper with hylomar instead of the permatex.

 
Those are cool looking heads. When you had them apart did you have them checked for flatness? A last resort try some radiator sealant . I probably will not take much and nobody will know.

I am looking forward to the pictures you mentioned.

It looks like two spark plugs per cylinder. What are you using for a distributor?
 
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Maybe Hylomar without the gasket; motorcycle cases are sealed that way. Either way, I would use hylomar over permatex if surfaces are good and flat.
 






Joel that is interesting about the hylomar without a gasket I will look in to that. I used the permatex at the time as it was to hand because I put it on the head stud threads.

Sturgis the ignition is a Nash twin fire.

Thanks for the input...
 
Do you have pictures of the nash twin fire? This something i have to see.
Are you from the united kingdom? I see a few handles with UK. Just wondering what it means

Thanks
 
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I've noticed that most if not all the more recent 2-piece head manufacturer's use screws around the plug bosses. Hylomar should work OK since it worked on Rolls Royce Merlin V-12 engines. I would use the more recent Loctite 515 and a bit of #50 silk thread around the bosses to insure a seal. That's how I seal Rolls-Royce cases now. An annular o-ring would have been the best bet but the Robert Roof heads go back a few more years than say the Frick types.

Kerby
 
If you want me to, i can take good measurements and pictures of the original gaskets on a set of Roof heads i have..? That might help you find the correct gasket material.
 
Do you have pictures of the nash twin fire? This something i have to see.
Are you from the united kingdom?

Thanks

Here you go.. and yes - England.



Old photo but you can see it. This is on a Norm Frick Angle Drive. Roof originally drove the ignition straight off the end of the cam... I guess that would have made the ignition wires a bigger headache than they are!



 
If you want me to, i can take good measurements and pictures of the original gaskets on a set of Roof heads i have..? That might help you find the correct gasket material.

Yes please. Would love to compare notes, Have you ever run them?
 
I've noticed that most if not all the more recent 2-piece head manufacturer's use screws around the plug bosses. Hylomar should work OK since it worked on Rolls Royce Merlin V-12 engines. I would use the more recent Loctite 515 and a bit of #50 silk thread around the bosses to insure a seal. That's how I seal Rolls-Royce cases now. An annular o-ring would have been the best bet but the Robert Roof heads go back a few more years than say the Frick types.

Kerby

Thanks, I hadn't considered loctite I will look in to the 515 and see if it is available over here.
 
Gary,

Any time a sealer is called for I use general purpose silicone sealer, found in the bathroom section in any DIY store.
Walks all over Hylomar and all the other sealers out there and you can get it in clear so it won't even show!
 
It would take a bit of work but there looks to be enough surface area there that you could do some type of o-ring setup using maybe a very thing piano wire and a small scribe around the surface. Otherwise I have had luck with Permatex Aviation Form-A-gasket , part # 80019
AVIATION FORM-A-GASKET Sealant 4 oz bottle
PERMATEX 80019
 
I was wondering, are the leaking plugs the lower ones on cylinders 2,3,6,7?

No from memory it was the lower ones on 3,4,7 and to a lesser extent the top on 2 and 6.

After reading up on the loctite 515 I think that is the way I am going to go in conjunction with the 7649n primer.

Thanks to everyone for the comments and suggestions. I will post up how it works out.
 
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