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Posted by: porsche-tom Nov 25 2014, 02:06 PM

so i posted before about my about replacing my fuel pump because whenever its hot out it just stops. i cleaned out the gas tank, replaced the fuel lines and replaced the pump with a rotary fuel pump previously recommended. while on the ramps it started fine. i drove it out of the garage and one block away it died again (its about 85 degrees out). it now will not start but i can hear the pump kicking on when ever i turn the key. i am going to wait until tonight when its cooler out and see if it changes but im getting pretty frustrated . does anybody have any ideas?.....please
1972 1.7 carb convert

Posted by: r_towle Nov 25 2014, 02:08 PM

fuel lines swapped backwards.
You want to have the feed line for the pump to be the larger of the two, closer to the passenger side of the car when looking from below.

Are you out of fuel also?

If you swapped the line, and its low, it may work when jacked up in the back because the return line is about 4 inches tall inside the tank.

The correct feed line is at the bottom of the tank.

Rich

Posted by: porsche-tom Nov 25 2014, 02:26 PM

the return line was previously blocked off. the lines are in the correct places and it has 2 gallons of fuel that should be enough fuel?

Posted by: wndsnd Nov 25 2014, 02:41 PM

If it is a carbed car, someone had to jump the pump probably at the relay board. Make sure all the connections are good and secure and are not vibrating around or that there is not a loose connector.

John

Posted by: Racer Chris Nov 25 2014, 02:53 PM

check for a kinked hose.

Posted by: jvmarino Nov 25 2014, 03:00 PM

You may also want to check the fuses on the relay board in the engine compartment. There are 2 bullet style fuses that may have intermittent connections depending on the temperature in the engine bay. If so, you need to clean the contacts and bend them closed more to make a tighter contact. Ask me how I know........

Jim

Posted by: RobW Nov 25 2014, 03:23 PM

You don't mention changing the fuel filter...

Posted by: porsche-tom Nov 25 2014, 03:40 PM

filter is new came with the pump.

Posted by: GeorgeRud Nov 25 2014, 03:44 PM

Is the fuel pump in the original position or has it been moved under the gas tank? Electric fuel pumps like to push fuel more than pull fuel.

Posted by: porsche-tom Nov 25 2014, 03:48 PM

the pump was already relocated to the front under the tank and i intstalled the new one in the same spot

Posted by: stugray Nov 25 2014, 05:21 PM

If the tank vents are clogged, it can pull a vacuum on the tank and stop flow.

when it does it again, take the gas cap off and see if it behaves differently.

Posted by: Mark Henry Nov 25 2014, 05:55 PM

In-tank filter screen?

Posted by: r_towle Nov 25 2014, 06:05 PM

It's a fuel problem.
So you state that you had it working before with no issues with the current hose.
It's either out of gas and not enough to get into the line, or its a kinked hose from when you put the tank back in after install.
It can work by using the return line, but it's about 2 gallons of fuel cause of the 4 inch pipe in the tank.
That is why I said you may have swapped hoses...
You said it worked while jacked up, did not work when on the ground....So it's a fuel level issue.

Could also be a kink
Get a mirror and verify there is no kink.
If you are patient with a mirror and flashlight, you can see almost all of it except the loop that goes toward the drivers side from the pump to the filter if it's in the 75/76 location.

Not a typical place to kink...more likely to kink right under the tank and sometimes you just need to loop it the right way from underneath and it will be ok.
Other times you need to pull the tank and do it again...

Tests I would do.
Is there fuel in the engine bay when the pump is running?
Should be a 65 psi stream of fuel...squirt it into a gas can.

If no fuel there, start looking for the kink.
Look for the kink first before you add more fuel to the tank.
You may need to pull up the tank to fix the kink.

Posted by: rhodyguy Nov 25 2014, 06:11 PM

note the carb conversion comment. pull the supply from the carb and check the flow. rotary pump?

Posted by: r_towle Nov 25 2014, 06:14 PM

Ok, so I will correct my post to say it will squirt at about 5 psi....

Posted by: rhodyguy Nov 25 2014, 06:18 PM

sounds like a plan.

Posted by: porsche-tom Nov 25 2014, 06:40 PM

i am going to try and lift up the gas tank and try to turn it over and see if it changes. ill let you guys know what i find. thank you all for the advice.

Posted by: porsche-tom Nov 25 2014, 07:25 PM

i lifted the tank to unkink any kinks and tried to start it nothing. i also took the gas cap off and nothing. i looked inside the tank and the filter is fully submerged. i also checked the fuel lines, i have the tank going into the filter and the filter into the pump and the pump into the engine. i also pulled the the inlet of the carb and got nothing.

Posted by: porsche-tom Nov 25 2014, 07:25 PM

i lifted the tank to unkink any kinks and tried to start it nothing. i also took the gas cap off and nothing. i looked inside the tank and the filter is fully submerged. i also checked the fuel lines, i have the tank going into the filter and the filter into the pump and the pump into the engine. i also pulled the the inlet of the carb and got nothing.

Posted by: wndsnd Nov 25 2014, 07:35 PM

Well I know what I would do but it is probably not a good idea.



Got any compressed air?

Posted by: wndsrfr Nov 25 2014, 07:52 PM

Wow, some kind of mystery.....gonna venture that the pump is wired backwards maybe? If not that, and you can clearly hear the pump running, then I'm betting that the screen inside the tank is blinded/clogged. Now, the previous comment about having an air compressor can be of some help here....you can disconnect the line going into the fuel pump and backflush that screen with a shot of compressed air--that'll get you going for a short while 'til the screen makes up again. Then Siphon out the fuel, pull the tank and pull that screen fitting out to be sure. Good luck and please post what you find out!

Posted by: r_towle Nov 25 2014, 08:05 PM

Sorry, pull the tank.

Posted by: cwpeden Nov 25 2014, 08:23 PM

In your tank you will one of these.

The top one will let your car run, the bottom one wont. Its on the suction side of the pump in the tank. Fully remove tank to replace.

Still cant figure out how the hair and lint got in my fuel tank?

Posted by: wndsrfr Nov 26 2014, 07:40 AM

Adult swim for a mouse sometime in the cars lifetime.....?

Posted by: bandjoey Nov 26 2014, 08:06 AM

Sometimes it's eliminate possible problems one piece at a time. Hook up the fuel pump to a portable gas can and let it run for a half hour and hot. Just my 2cents. Good luck.

Posted by: Mikey914 Nov 26 2014, 09:30 AM

Really easy to pinch a hose. I had exactly this problem, and that's what it was. That and the rotary pump was a piece of crap, even though it was new it went out a week later, maybe because it was pinched for awhile, but it wasn't very long.

Posted by: cwpeden Dec 8 2014, 01:47 AM

So how did it turn out?