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pontiacvince 07-10-2022 07:35 PM

Fuel problem
 
1 Attachment(s)
Not sure what my problem is, but I cannot get fuel from the tank to the carb. I have been filling the bowl through the vent tube about 20 tomes. It fires up and runs fine and sounds DAMN GOOD with the Flowmasters on the headers.....until the bowl runs out. I have chased all of the lines from the tank to the pump and can't find any leaks. The vent line runs from the vent tubes in the back to the canister on the fender.
Any ideas???

BAD1916 07-10-2022 09:20 PM

Re: Fuel problem
 
I would disconnect the line from the tank to the fuel pump and make sure you are getting fuel there. I would also disconnect the line from the fuel pump to the carb. If you are getting fuel there there’s something clogged in the carb. If not and there was fuel at the input to the pump then the pump is most likely your problem. I have had issues on old thunderbirds where we weren’t getting fuel and we had to pressurize the fuel tank by using air from a compressor and blowing it into the fuel filler.

pontiacvince 07-10-2022 10:32 PM

Re: Fuel problem
 
I went through all of my lines this morning. I installed a 40gal. tank with new sending unit, and all new lines front to back.
I pulled the pump and still no fuel. The pump rod is working.

BAD1916 07-10-2022 11:35 PM

Re: Fuel problem
 
Have you tried running a hose into a gas can to verify that the pump is functional. Even if it’s new doesn’t mean it’s good.

pontiacvince 07-11-2022 01:08 AM

Re: Fuel problem
 
I'm gonna pressurize the tank tomorrow to verify the lines aren't plugged. Then I'll test the pump.

kwmech 07-11-2022 03:32 PM

Re: Fuel problem
 
Fuel line to the pump is incorrectly hooked up at the tank??

HO455 07-11-2022 07:39 PM

Re: Fuel problem
 
1 Attachment(s)
Have you replaced the 6 inch loop of hose inside the frame rail just in front of the crossmember (on a T400 truck)? That hose will go bad and the pump will only suck air. It won't leak fuel unless you pressurize the line.

I replaced mine with a short piece of steel line and 2 compression fittings. See photo.

I bent my lines straight but they have 90 degree bends where the hose attaches from the factory.

pontiacvince 07-15-2022 02:08 PM

Re: Fuel problem
 
I pressurized the tank and pushed the fuel to the front. Problem solved!

HO455 07-15-2022 02:31 PM

Re: Fuel problem
 
Good to hear.

nightmare 07-15-2022 07:09 PM

Re: Fuel problem
 
Quote:

Originally Posted by pontiacvince (Post 9101845)
I pressurized the tank and pushed the fuel to the front. Problem solved!

Until you run out of fuel. You may have a problem with the pump not being able to suck the fuel all the way to the front. You may either have a bad fuel pump, or need to make sure you pressurize the tank every time you fill up

pontiacvince 07-15-2022 07:32 PM

Re: Fuel problem
 
3 Attachment(s)
So far, after breaking in the engine and running it to check everything, it runs and sounds really good. Excellent oil pressure, and great vacuum. Hasn't overheated. Bled the air out of the new power steering pump and steering gear. I put the Flowmasters directly on the headers and it sounds REALLY good! Can't wait to get the full exhaust on.


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