Phenolic insulator

30-9

Well-known member
I have tri carbs w 1 inch aluminum spacers - does it matter if I add the 1/4 inch phenolic to top of manifold or if I add above 1 inch spacer right below carbs?
 
I'm running triples with the same 1" aluminum spacers. I just used a thin gasket on each side of the spacer. I don't see a need for the phenolic spacer because the aluminum dissipates the heat very well.
But in answer to your question I would put it directly below the carb if I were putting one in.
 
It was 107° in Sacramento today. I was out in the hottest part of the day in stop and go traffic. No fuel boiling; instant starting after sitting in parking lots, thanks to Bob Drake's phenolic spacer. Not braggin', just saying they make a HUGE difference. Prior to installation, on even a cooler day, fuel would routinely boil and flood engine. By the way, using a standard mechanical fuel pump.
 
Wouldn't think the fuel pump would be the issue. If this is a persistent problem might consider the return fuel line being discussed the last couple on days here on the barn. Might give the spacers a try first, simpler.
 
Ya i recently installed the 1" spacers hoping it would help but pulled in garage today and opened hood and heard the boiling - hence my questions about the phenolic......
 
Would the aluminum spacer or phenolic insulator not work more effectively under the fuel pump rather than the carburetor?
 
Would the aluminum spacer or phenolic insulator not work more effectively under the fuel pump rather than the carburetor?
I might be wrong, but I didn't think he was talking vapor lock, he is having an issue with the fuel boiling out of the carbs. From the description this is occurring after it is stopped.
 
I might be wrong, but I didn't think he was talking vapor lock, he is having an issue with the fuel boiling out of the carbs. From the description this is occurring after it is stopped.

Right...that's why it has nothing to do with the fuel pump. It's excess heat transferring from the manifold to the carburetor.
 
Correct no mech pump. Car was running rough on way home from vfw. Opened hood at home and could hear carbs boiling. I thought elec pump & 1" spacers would solve vapor lock, but wrong again. I did notice a half pound drop in fuel pressure ( normally 3 went to 2.5)

Hearing Ralph w same setup diving w temp 107 has me baffled.unless he's runnin no hood..What's experts here think? Add 3 phenolic insulators or replace elec pump?
 
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Would the aluminum spacer or phenolic insulator not work more effectively under the fuel pump rather than the carburetor?

Soooooo, Lawson........how would that work with the fuel pump pushrod being a fixed length? NOT too well, I think. DD
 
Spent $90 on the 1" aluminum adding 1/4 more should not affect look esp since it's black and will match bottom of carb
 
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