Mechanical fuel pump diagnosis

[dremu]

This truck may never work right again 74 crew cab, 454.

Besides my various brake and steering issues, now she doesn't want to run. Turns over, but doesn't catch. I have 10.5-11V going to the HEI and the timing light blinks, so it looks like I've got fire.

I took the carb fuel line off and stuck it into a container ... gas ends up in it, but I donno that it's a lot. Bypass the filter, same thing.

I'm suspicious of the fuel pump; short of a pressure gauge, which I don't have, how do I diagnose whether the booger has gone out on me? Replace it and see?

Last question for the day, I promise, if for no other reason than I'm tired of fighting the thing and only making it worse

-- A

 

[sled_dog]

timing light flashing does NOT mean you have spark or a good spark. pull a plug, if its destroyed that could obviouslly be a problem. Check spark out of the engine, not just with a timing light.

 

[dremu]

timing light flashing does NOT mean you have spark or a good spark. pull a plug, if its destroyed that could obviouslly be a problem. Check spark out of the engine, not just with a timing light.

Fair nuff. But the damn thing ran half an hour ago and all I've played with is the power steering. Really. :|

-- A

 

[zeroz400]

You dont really need a pressure tester to figure out if your getting enough fuel. Need to do a volume test, you got a manual for your truck? The manual will say how much fuel theres needs to be in a given time, usually 10-15seconds of cranking. If you get the desired amount of fuel before that time you should be fine.

 

[dremu]

timing light flashing does NOT mean you have spark or a good spark. pull a plug, if its destroyed that could obviouslly be a problem. Check spark out of the engine, not just with a timing light.

SledDog, you're right on.

I also ran the battery dead and was charging it yesterday ... and started it with the charger connected running, which I KNEW as soon as I did it was prolly dumb. (This truck has HEI, which my other ones don't.)

Raped my old distributor for the (real GM) ignition module and swapped it in, and boom, she fires right up!

Thanks again all!

-- A

 

[jeeptuff]

That's a kick in the ass isn't it??? Runs fine to don't run at all... Glad to see you got the issue worked out..

 

[dremu]

That's a kick in the ass isn't it??? Runs fine to don't run at all... Glad to see you got the issue worked out..

Thanks. Now all I gotta do is fix the steering and brakes

-- A