HD6 Carburetor Spacer Blocks

[cdwatson]

I have removed the carbs to replace the gaskets to the manifold to fix a vacuum leak. I found the spacers between the manifold and heat shield are actually 3 spacers stacked up with no kind of sealing material between them. I am thinking this is also a source of leakage. Should the spacers be one solid piece? I thought of "gluing" the 3 layers together with a thin layer of gasket silicone. Would this impede the insulating properties of the spacers?

 

[andrea]

HI Chris
Silicone can be a great idea- BUT your car have the HEAT SHIELD from carburetors and intake manifold?
https://picasaweb.google.com/112770...6RICOSTRUZIONECARBURATORI#5532297797219791234
in this case two spacers and a gasket from intake and heath shield-- and a spacer and a gasket from carburetors and heath shield

 

[steveg]

Hylomar might be better than silicone as it wouldn't dry and leave glops hanging out on the inside impeding airflow.

As you can see from Andrea's picture, you need enough spacers and/or gaskets for your heat shield to clear the lugs on the manifold.

 

[cdwatson]

I actually have 4 spacers in my setup, 3 between the manifold and heat shield and one between the heat shield and carbs. I wasn't thinking of eliminating the spacers, just sealing any possible leaks between them since there is no gasket between them.

 

[andrea]

Gaskets have a great part to eliminate vacuum air problems, sealing perfectly different surfaces, if have the correct thickness ( avoid the lightweight one)
-hylomar or red silicone can solve the spacers problems, if surfaces aren't perfectly flat, no problem for insulating problems with them, they have same insulation propriety
Obvious: Also bolts and washers pressure have a big effect

Strange problem Chris-my spacers/gasket aren't -on my opinion- perfects, but NO air leaks, have you controlled the flat steel surface of the Heat shield in the carburetor zone? Folding here can be the problem !
also a the vacuum pipe to the distributor loosen bolt-or intake manifold sealing must be controlled
Cheers