engine and drivetrain Electric Fuel Pump Pumping - No Fuel In Filter

[dasfrogger]

First - I tried searching and didn't find anything related - If this has been covered please teach me how to search.

 

Problem - I just replaced my fuel filter and now I'm not seeing any fuel come thru the filter. Before replacement fuel flowed thru the filter well - no surging, etc. Now I can't get a drop to come thru.

My setup - My car is a 73 auto, Weber downdraft carb, running an electric fuel pump (from IE) in the trunk.

 

The setup was : Tank - Filter - Pump - Carb. After asking a few questions I had gotten the advice to put the filter after the pump since the electric pump doesn't suck as well as it pushes and with the filter after the pump it can pull fuel easier. After making the switch i saw no change.

 

I had this same issue when I installed the pump a few thousand miles ago, and I honestly can't remember what I did to fix it. Anyone have any ideas on what I can do to fix this?

 

Pictures of the setup:

Filter before pump;

 

Filter after pump:

Edited September 3, 2013 by dasfrogger

[TobyB]

Pull the pickup and clean the screen.

 

Pull the pickup, unclog the tube, and find the screen and put it back on the pickup!

 

heh

 

t

[dasfrogger]

Pulled the sender - cleaned the screen. Is it supposed to be black? Didn't change color no matter what I did.

 

 

Doesn't matter much now - The screen was kind of jammed in the tube. didn't want to re install. Thought i had it jammed in again and as soon as it hit the gas it fell off into the tank. Effff. Hopefully I have a spare sender assembly at my workspace.

 

Result: still no change. Any other thoughts?

 

On side note every time I really enjoy this car, or get something done for the good of the car it always does something like this. Every. Time.

Edited September 3, 2013 by dasfrogger

[allbim]

There is a short line that you have plugged with a bolt. Blow into that to pressurize the tank slightly and force fuel into the pump. Perhaps your pump is marginal and needs priming. Make sure the end of that short line is not submerged in fuel, so that it can't squirt out when you remove the source of pressure.

Edited September 4, 2013 by allbim

[M3M3M3]

There is a short line that you have plugged with a bolt. Blow into that to pressurize the tank slightly and force fuel into the pump. Perhaps your pump is marginal and needs priming. Make sure the end of that short line is not submerged in fuel, so that it can't squirt out when you remove the source of pressure.

bad idea that is not going to work.  the tank is vented at the fill tube....

 

how old is the pump?  how much voltage is getting to it?  do you have a perfect airtight seal at the hose fitting on pickup and pump?  is the pump wired correctly (not backwards)?  is the pump plumbed correctly (not backwards)?

 

any good elec pump should pull enough suction to self prime...

 

take hose off pickup, take pickup out of tank.  put hose directly into fuel in tank.  try pump again. (do not try by sparking the wire connections together!!!!!!)  if this works, pinch off tank end of hose, replace pickup and reattach hose over the white plastic spacer that is on the brass pickup tube.  it is there, right?

Edited September 4, 2013 by mlytle

[Preyupy]

It is possible that the float bowl is full and there is no flow.  Try taking the hose off at the carburetor and put it into something and turn on the pump for a few seconds that should allow the pump to prime and flow some fuel through the filter. 

[allbim]

It is possible that the float bowl is full and there is no flow.  Try taking the hose off at the carburetor and put it into something and turn on the pump for a few seconds that should allow the pump to prime and flow some fuel through the filter. 

That makes to much sense and it's to easy.

[TobyB]

 

That makes to much sense and it's to easy.

Far too much sense...

 

t

[dasfrogger]

 

how old is the pump?  how much voltage is getting to it?  do you have a perfect airtight seal at the hose fitting on pickup and pump?  is the pump wired correctly (not backwards)?  is the pump plumbed correctly (not backwards)?

 

any good elec pump should pull enough suction to self prime...

 

take hose off pickup, take pickup out of tank.  put hose directly into fuel in tank.  try pump again. (do not try by sparking the wire connections together!!!!!!)  if this works, pinch off tank end of hose, replace pickup and reattach hose over the white plastic spacer that is on the brass pickup tube.  it is there, right?

Pump is probably 3 or 4 years old, not even 8k miles. It has worked with no issues until i changed the fuel filter (it even worked for 25 miles this afternoon).

Nothing has changed w/ pump wiring or plumbing. Seals seem good - double checked.

 

no white plastic spacer on pickup tube. never has been one. I will try dropping hose into tank directly - i was thinking of trying that.

 

 

It is possible that the float bowl is full and there is no flow.  Try taking the hose off at the carburetor and put it into something and turn on the pump for a few seconds that should allow the pump to prime and flow some fuel through the filter. 

 

float bowl is dry - i know because after changing the filter I turned the car on and it ran for a bit before dying. Didn't check immediately for flow because I didn't anticipate the possibility of any problems. Car died and I realized filter was bone dry. If the hose straight to the tank method doesn't work I'll try this anyway.

 

how old is the pump?  how much voltage is getting to it?  do you have a perfect airtight seal at the hose fitting on pickup and pump?  is the pump wired correctly (not backwards)?  is the pump plumbed correctly (not backwards)?

 

any good elec pump should pull enough suction to self prime...

 

take hose off pickup, take pickup out of tank.  put hose directly into fuel in tank.  try pump again. (do not try by sparking the wire connections together!!!!!!)  if this works, pinch off tank end of hose, replace pickup and reattach hose over the white plastic spacer that is on the brass pickup tube.  it is there, right?

Pump is probably 3 or 4 years old, not even 8k miles. It has worked with no issues until i changed the fuel filter (it even worked for 25 miles this afternoon).

Nothing has changed w/ pump wiring or plumbing. Seals seem good - double checked.

 

no white plastic spacer on pickup tube. never has been one. I will try dropping hose into tank directly - i was thinking of trying that.

 

 

It is possible that the float bowl is full and there is no flow.  Try taking the hose off at the carburetor and put it into something and turn on the pump for a few seconds that should allow the pump to prime and flow some fuel through the filter. 

 

float bowl is dry - i know because after changing the filter I turned the car on and it ran for a bit before dying. Didn't check immediately for flow because I didn't anticipate the possibility of any problems. Car died and I realized filter was bone dry. If the hose straight to the tank method doesn't work I'll try this anyway.

[M3M3M3]

the white spacer is needed.  the fuel hose is too big for the metal pickup.  the spacer adapts the pickup size to the hose size.  without it you will not get a good seal and the fuel pump will suck air.  this may have been your problem all along.

 

the part is available and is cheap. there was a thread on it recently.

[dbmw2002]

Check all connections aft of pump, these are suction cons, need to be tight and right for fuel pump to work, thro a different filter on, weirder things have happened, no worries about cons after pump you will smell and see these pronto, you do have gas in the tank, dumb dumb dumb Q but ask me how I know............

[dasfrogger]

Tank full of gas - all connections were as they were before replacement (car ran great).

 

Got a chance to dip fuel hose directly into tank - tried running pump and still no suction. Any other ideas on what could be going on?

 

 

I've got a new mechanical pump that i've been meaning to install. Maybe it's time. Anyone have any tips for a successful instillation?

[dbmw2002]

Just checked and there is room in cd's neighbors pool for failed electric pumps, a passel of them already reside there, if your head is set up for a manual pump I wouldnt hesitate on the switch, only reason I run electric is my head is a later 121 and is not set up for manual. First test pump by pushing rapidly on plunger with hose in gas, it will spurt and flow qwikly if good, dont forget the spacer between the pump and head and be done with the lectric hassle

[mike472]

Use the stock pump if possible. It is a different kind of pump that uses a diaphragm which self primes much more easily and has the power to pull fuel from up front. Your electric setup has too long a run of tubing from the tank to the pump making it even harder for the electic pump. Also you should put the filter up front in the engine compartment aNd shorten up the amount of tubing you're using at the tank. It may be air bound somehow. Those pumps are not as reliable as the stock pump. The only reason to not use it is if your head has no hole for the stock fuel pump. Little white bushing is essential. The closest American fuel line is a loose fit and some people use it instead of the metric line, but both will suck air if you don't tighten the hell out of them without that white bushing. Try the dip in the tank test Marshall described. That should determine whether the pumps gone bad.

[M3M3M3]

Use the stock pump if possible. It is a different kind of pump that uses a diaphragm which self primes much more easily and has the power to pull fuel from up front. Your electric setup has too long a run of tubing from the tank to the pump making it even harder for the electic pump. Also you should put the filter up front in the engine compartment aNd shorten up the amount of tubing you're using at the tank. It may be air bound somehow. Those pumps are not as reliable as the stock pump. The only reason to not use it is if your head has no hole for the stock fuel pump. Little white bushing is essential. The closest American fuel line is a loose fit and some people use it instead of the metric line, but both will suck air if you don't tighten the hell out of them without that white bushing. Try the dip in the tank test Marshall described. That should determine whether the pumps gone bad.

some good info there, but to clarify..

 

nothing wrong with electric pumps.  plenty of power for the task.  primes as easy if not easier than the mechanical one, especially if the pump is right next to the tank..unlike mech pumps which have to pull from the engine compt.  one of my 02's had the elec pump in the engine compt and never had an issue with priming.  there are many holy war threads claiming one is better than the other, but the reality is either option works well in a 2002.

 

yes, little white bushing is needed.

 

closest american fuel line is 5/16ths, which is basically identical to bmw 8mm ( 0.002 percent different ID) and works perfectly without tightening the hell out of it.

Edited September 9, 2013 by mlytle