Fuel pump bad?

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remytherat

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My has been running just fine, but a few days ago I parked it and when I went to start it back up, the fuel filter was bone dry and was not filling with fuel at all while cranking. What are some things I should check?
 
If you suspect the fuel pump.

An easy place to start is at the fuel filter.

Remove it, then put some tube on the outlet from the fuel pump into a gas can.


Crank the engine and if fuel comes out into the gas can the pump and the lines to the tank and the vent line MIGHT be good.

Next you can add fuel to the carb bowels, and if the starts and runs the carb MIGHT be ok.

The FSM has full test procedures
 
i don't know if you've rebuilt the system-- ie. pick up, tank, lines, etc. but besides the obvious of the pump quitting on you here's a few other possibilities:

>pick up not at the right angle/close enough to the tank bottom
>pick up sock clogged with debris or folded over on self
>hole in a hard line or soft line causing the pump to suck air
>debris from old hard/soft lines or tank clogging up the pump
>kinked soft line in the system

but as above, i'd check the pump first.
 
I went ahead and threw in a new pump since its a pretty easy install. Didn't fix the problem, but at least I have a new pump.
I blew into the line from the pump to the tank to check for any holes and I wasn't able to blow any air into it.
I am thinking that the pickup must be clogged.
Any ways to confirm? And can I replace it with the tank in the car?
 
I went ahead and threw in a new pump since its a pretty easy install. Didn't fix the problem, but at least I have a new pump.
I blew into the line from the pump to the tank to check for any holes and I wasn't able to blow any air into it.
I am thinking that the pickup must be clogged.
Any ways to confirm? And can I replace it with the tank in the car?
disconnect the line at the sending unit and hook up a mityvac or just suck on it and see if you get a mouth full of gas.

you can replace with the tank in the car.

also, if you haven't confirm that your pump-- even a new one-- is operational. run a line to a gas can and see if it's pumping to the carb.

if that's not doing the things and stuff, then you may have a bigger problem, possibly the fuel pump eccentric.
 
Ok will do.

And about the pump eccentric, here is what the old pump looked like. Is this wear excessive?




IMG_2877.jpg
 
oh, something to keep in mind is that the filter sock can collapse under suction and then "relax" again allowing for flow, which can have you chasing your *** on diagnosis. also, it can totally fall off the end of the unit allowing all the crap in the tank to get sucked up and destroy a pump in short order.

i don't like the galling on the arm there, but without knowing how many miles it doesn't look totally waxed ***.
 
If you can not move air from the inlet to the water pump into the tank.
Then as stated disconnect the fuel line at the sender and try again.

That will tell you if the line is clear.

Then blow air into the sender outlet and listen for bubbles (assumed you have enough fuel in the tank) take the fuel cap off during this test.

No movement or bubbles, clogged pickup.


Rais rear of car and support on jack stands

Allow the rear end to sag. That will give you a lot of sender room to work with.

I'll get greef for this, but do yourself a favor and get a proper lock tool removal tool, 20 bucks of ease. You can do it with a screwdriver but...

Be sure tank is below 1/4 tank.


Replacement senders ALL suck.

Your gauge will never be correct again.

If at all possible replace the sock only and maybe the float.

If the sender is not functional there are repair places.
 
Check all rubber hoses in fuel system, ethanol fuel is very harsh on rubber. It can and will eat or harden the rubber causing the hose to fail.
 

You can do it with a screwdriver but...
that's a possible way to create a spark...
therefore a very bad idea.

Acceptable tools for using the striking method are brass or aluminum rod, or very hard wood block.
 
Yeah so tank is rusted and little bits are kind of everywhere in the lines and pickup is clogged. I'm thinking of replacing the tank and lines all together because if I replace the pickup w/o doing anything about all the **** thats still in the tank I'm not actually fixing anything. Not stoked on having a messed up gas gauge tho.
 
There's supposed to be a 'sock' filter on the pickup. I've seen two versions. Regardless, that's what's needed to keep most of the stuff out of the system. The filter before the carb gets the tiny stuff that gets by.
I'd change those, the rubber connections, do a visual check of the steel lines, and see how it goes.
Be careful of the resistor wound board when removing the sending unit. Its a bit fragile.

If the tank is so bad that you decide to clean it out, then its probably worth the hassle of dropping it.
 
Yeah so tank is rusted and little bits are kind of everywhere in the lines and pickup is clogged. I'm thinking of replacing the tank and lines all together because if I replace the pickup w/o doing anything about all the **** thats still in the tank I'm not actually fixing anything. Not stoked on having a messed up gas gauge tho.
The replacement tank is not that expensive. Check out Tanks Inc.
 
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