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Stromberg Carbs Overflowing

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TR4

TR4

Jedi Knight
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I have a little fuel coming out at the choke shafts on my Stromberg Carbs. Could this be due to the floats being set at the incorrect height? Both carbs have just been rebuilt. I installed new fuel lines and cleaned them prior to installing them and I also installed a new fuel filter so I am fairly sure this is not a sediment issue. I also checked the fuel pressure and have 1-1/2 lbs of pressure according to the fuel pressure guage. The carbs are working but I need to fix the leak.

I plan to remove the carbs this weekend to check the float height. Is there anything else I should check?
 
A couple of things to think about:

When the carbs were rebuilt, were new throttle shafts installed? If the old ones are worn you might get some leakage there, although it's usually a vacuum issue.

Were the carb body shaft seals rebushed, or replaced?

I don't know if a sticking float valve could cause leakage there but they are blamed for almost everything else, plus they're tricky to diagnose.

It's been a while since I was inside a ZS so I may be off a bit here.
 
Check the needle and seat as well. I like to go over to grosse jets whenever possible. It's been a while, so I'm not even sure if they still sell those things.
 
The problem might be a worn bushing or shaft. Here you'll see the choke assembly, bushing and shaft.
Chokeassembly.jpg
 
I recently went through this with my SU's and found that the floats were full of gasoline. I changed them and it happened again within a couple of months. I wound up buying a set from Burlen that are supposedly ethanol resistant and so far (about a month) they are working fine.

Good Luck....Dennis
 
Not an expert, but it does sound like a potential float height issue to me. If the needle valve was stuck you'd get a lot of gasoline coming out of the vent in the front of the car which is what I experienced a few years ago.
 
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