Carb insulator

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Jan 5, 2016
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Boise, Idaho
I have an early model 1964 fj40 with an f-engine and oem single barrel carb. I am not sure if this year had a carb insulator. Is it necessary?
 
My 1966 had an insulator with a vacuum port. The insulator was cracked, so I filled the vacuum port area with epoxy and restored the insulator to have no vacuum port. With no insulator, my stock airbox would not line up with the carb and the studs in the manifold would be too long.

Mine is exactly 14mm thick, if you need to get one machined out of aluminum.

Hope this helps. My 1966 might not be identical to yours, so research thoroughly. I'd test-fit the parts you have to see how it all lines up.
 
Insulator image:
20160615_141058.jpg
 
It's a thermal insulator to help keep the fuel in the carb from boiling off when you're idling.


So, making one out of aluminum is not the best choice. Some sort of non conducting material would be much better
 
Ok this is funny. I was just thinking (jokingly) maybe you could make one out of a space shuttle tile. For fun I Googled it up and apparently they were for sale as early as 2010 for like $23.40. I doubt you could machine it for anything but heck, I'd of bought one just for kicks.

Space shuttle tiles for sale
 
Lol awesome..


"Actually it is rocket science.."
 
So, making one out of aluminum is not the best choice. Some sort of non conducting material would be much better

I used Mr. Gasket for my gasket on either side of the insulator. I'm thinking that if you machined one from aluminum, but used something thicker like Mr. Gasket as I did, you may have decent results.

You can buy nylon/delrin or other plastics in thick sheets, according to a quick Google search. That may be the best bet.
 
Anyone know of a current source for these for the single barrel carbs? The one on my truck is mostly mush and delaminating. Looks like a whole pile of gaskets stacked up 14 mm tall. No vacuum port on my ‘64.
 
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Cruiser Outfitters has carb rebuild kits and base gaskets, but no insulators for the single barrel carbs. Still looking.
 
The 64 is pre-PVC, and is thinner than the 66 that had the PVC. I have an NOS 64 insulator. It is not for sale. But I can get a thickness measurement so you can make something ...other than a stack of gaskets.
 
Thanks, @65swb45

With a base gasket as a shape template, and the thickness, these should not be that difficult to make. I would suspect the originals were Bakelite, but some other modern heat resistant plastic that is easy to machine should work as well.
 
Thanks, @65swb45

With a base gasket as a shape template, and the thickness, these should not be that difficult to make. I would suspect the originals were Bakelite, but some other modern heat resistant plastic that is easy to machine should work as well.

Negative. The 66 was Bakelite, but the 64 was made out of the same material as the intake/exhaust gasket, probably asbestos. Doesn’t mean you can’t make one out of Bakelite.
 
Negative. The 66 was Bakelite, but the 64 was made out of the same material as the intake/exhaust gasket, probably asbestos. Doesn’t mean you can’t make one out of Bakelite.
Roger that. That means the one I pulled off my truck probably was original, just badly deteriorated. Still need to find or make a suitable replacement.
 
Still looking for a solution for this insulator. I got my rebuilt carb back from Mark today, but can’t install it until I find a solution of some sort for the insulator/spacer. Anyone able to tell me how thick the non-PCV part should be?
 
The later PCV version is 14mm, but Mark noted above that the earlier one was thinner. I suppose the exact thickness is not critical. The remains of my original are 8mm, so I’m going to guess it was either 10 or 12mm originally.

Any suggestions on where to buy 3/8” or 7/16” phenolic sheet?

Edit - I slipped my carb on with the 8mm remains, and I don’t think 10mm will be enough to allow the carb to mount w/o the inboard manifold stud interfering with the carb. 12mm will probably be ok, but 14mm might be too thick to get full thread engagement. So 12mm was most likely the factory thickness. For here in the states with material likely in inch sizes, I’d probably be ok with either 7/16” or maybe 1/2”.
 
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My approach to getting the thickness correct:

Figure out what thickness is appropriate to keep the studs from interfering with the throttle plate housing, while getting you as much thread engagement possible. I can't tell from your post above if you are remembering to account for gasket thickness, but I definitely recommend trying to come up with a way to measure compressed gasket thickness before you select your materials.

Link: (I just searched "1/2 inch thick phenolic sheet" and this was in the top 5 hits)
 

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