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Old 04-03-2021, 05:12 PM   #26
Droff
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Re: Carb leak at choke location

It's been a while, I'm not a fast worker and had to consider weather in all this as the truck is outside. I got the tank cleaned and I coated it with a POR15 kit, installed a new sending unit, replaced all the fuel flexible lines and filters. Today I got the tank in, everything connected and added some fuel. Now the problem.

The truck will start but I can't keep it running. It's getting fuel but I think it's getting too much fuel. I would have to say I rebuilt the carb correctly so not sure why right now. I'm still seeping fuel from the same location before the rebuild and I can also hear gas running into the carb after trying to get it started. This is after I get out of the cab and walk around to the front of the truck. Is the next step in the process a regulator?
Thanks.
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Old 04-03-2021, 06:17 PM   #27
geezer#99
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Re: Carb leak at choke location

Close to the First step shoulda been a regulator.
Choose one that limits pressure to 5.5 psi.

Here’s a couple that go to 6psi.
Found 7 more there that are rated 1-4.


https://www.summitracing.com/search/...ange-psi%3a1-6

Last edited by geezer#99; 04-03-2021 at 06:31 PM.
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Old 04-03-2021, 06:40 PM   #28
HO455
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Re: Carb leak at choke location

Quote:
Originally Posted by Droff View Post
It's been a while, I'm not a fast worker and had to consider weather in all this as the truck is outside. I got the tank cleaned and I coated it with a POR15 kit, installed a new sending unit, replaced all the fuel flexible lines and filters. Today I got the tank in, everything connected and added some fuel. Now the problem.

The truck will start but I can't keep it running. It's getting fuel but I think it's getting too much fuel. I would have to say I rebuilt the carb correctly so not sure why right now. I'm still seeping fuel from the same location before the rebuild and I can also hear gas running into the carb after trying to get it started. This is after I get out of the cab and walk around to the front of the truck. Is the next step in the process a regulator?
Thanks.
I would go back and double check the float settings. At the same time do a close inspection of the float for fluid inside of it if it is brass. If it is a plastic float it may be fuel soaked. If a float has either condition it will not float as designed causing the fuel level to be too high which causes flooding. Don't be afraid to set the float lower to see if your problem disappears.
While you have the top off of the carburetor inspect the bowl, needle and seat for new debris that might have been washed to the carb after cleaning and reassembly.
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The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377
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Old 04-03-2021, 09:13 PM   #29
tim_mc
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Re: Carb leak at choke location

Yes sir, a regulator is needed for most (dare I say all) Edelbrock carbs. Most mechanical pumps sold today are probably pushing 8-9 PSI minimum and likely more. Your rebuild likely improved fuel flow. The Mr Gasket regulator I have seems to work OK and the VDO fuel pressure gauge reads about 4.5-5 PSI. In fact I just checked it today after a run to the store since it had been a few weeks since I drove the truck. Before I installed the regulator, the fuel pump was pushing fuel past the float valve. It was running too rich, had black soot out of the exhaust and the garage smelled of gasoline. As HO455 mentioned, definitely check the float level and if it's soaked or holding fuel and if anything is blocking the needle & seat.
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Last edited by tim_mc; 04-03-2021 at 09:22 PM.
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