Fuel Pump Nightmare!! Help!

[Hudso056]

Ok, guys just my second post so be a little easy. I've got a 73 40 with the original F engine and weber 38. The aftermarket electric fuel pump was knocking and wasn't pushing any gas so I replaced it Saturday. Drove it Sunday and all was well, cranked it up at lunch fine. I tried to crank it up to leave the house after lunch, and it wouldn't start. Same thing, fuel pump knocking and no gas at the carb. I though hey, maybe a bad pump. I take it back to napa, and get another pump same model. Slap that one in and it primes and fires right up. I drovit around the block and pulled into the driveway and it died...Same song 3rd verse. The fuel pump is knocking and no gas at the carb.

Fuel line runs from tank->inline fuel filter (brand new)->electric fuel pump(3rd one)->fuel pressure regulator->carb.

Testing done so far.
1. I dropped intake line to the pump in a bucket of gas...no suck.
2. I took the line off the top of the fuel pump and you can feel it pushing air...
3. I can syphon from the tank through existing lines.

Sorry that was so long. I will update with pics tomorrow if you guys wanna see the ride, but this problem is driving me crazy. Any Ideas PLEASE??

 

[kurtnkegger]

I'm not savvy on the webber carb, but could it be you have a stuck float? If you pull the fuel line at the carb, do you have fuel if you activate your pump?

 

[misupratwin]

most electric fuel pumps need to be mounted as close (within about 12 inches)as possible to the tank and below the tank. you could also have a crack in the fuel line ,allowing the pump to suck air. try setting your bucket on top of the fender with a hose at the bottom of the bucket to the pump then to you carb (most small inexpensive electric fuel pumps relie on gravity to keep them primed)

 

[Shark56]

ALL-FOREIGN CAR PARTS - Import & Domestic Car Parts, Import & Domestic Truck Parts, Brakes, Rotors, Distrubutors Fuel Pump&mode=PA

Try these guys for OEM pump.

 

[Hudso056]

Thanks guys, I will try placing the bucket above the pump. I just rebuilt the carb and I know it is good. It wouldn't have been able to run with a stuck float...i think. I drove it on a 100 mile trip before this started. It feels like it just loses its prime and after that it can't get it back. Thanks for the link shark. I'm going to give it one more week of fumbling before I go manual.

 

[FJ40WY]

x2 on the crack/vacuum leak in the suction side of the fuel system. is the gas cap venting properly? That pump should prime. A new part just means it hasn't been used yet I bought a lot of motorcycle parts for customers that needed a lot of TLC out of the box before I installed them. Several aftermarket electrical parts that needed disassembled and repaired before installation. I guess i'm saying it could be another junk pump Can you go back to a mechanical pump?

 

[Hudso056]

Yes, i'm looking into putting a manual back on. I recently drove off with the OEM gas cap sitting on my tire from the gas station and had to buy a generic cap from napa. It is a locking cap with a key....thank this could be the issue?? I also think the pump is even if not higher than the tank....

 

[Elbert]

if old electric pump worked fine then new pump should be ok (location)...as noted pump should be bellow the tank. (If it worked before why change now)... Leave the fuel tank cap off and test drive to see what happens.

 

[Hudso056]

Ok, took cap off and lowered pump still same problem. I bought a kyoshan manual pump. The paperwork that came with it says it needs a spacer...PO just put a plate over and I'm guessing threw away the spacer. Does anybody know if the HAS to be installed. It's a 12/73 1F.

 

[Poser]

Ok, took cap off and lowered pump still same problem. I bought a kyoshan manual pump. The paperwork that came with it says it needs a spacer...PO just put a plate over and I'm guessing threw away the spacer. Does anybody know if the HAS to be installed. It's a 12/73 1F.

Post up a picture of the fuel pump you have...

 

[mydogpea]

Not positive on this but I think up to 9/73 you need a spacer on the F engine. I don't think you need one for 12/73 F engine, again, I'm not 100% sure on this but if you need one, I have a new one you can have for the cost of shipping...5 bucks.

 

[Hudso056]

http://www.flickr.com/photos/60500026@N05/5519963133

http://www.flickr.com/photos/60500026@N05/5520554026

Here is a pic o the pump i have. The paper work said it needed an insulator...? I can't find anything for a 12/73 or higher spacer on any websites either. I found some for 6/78 - 8/87 and 65-9/73. I just don't want to hurt the egine.

 

[mydogpea]

Did the mech. pump come with mounting bolts?

 

[Roboosfj40s]

I could not find a OEM mechanical pump where I live. I was told to get an electric pump for a Suzuki Multi-Cab truck. I am not5 sure if they have those in the U.S. but it works great with the OEM Carb. Off angle up down seems it does not make a difference. However, I did have to mount it down at least mid tank level just under the battery box. My rig is a 74-78-79-81-Etc haa haa!

 

[Hudso056]

The mechanical pump didn't come anything but the pump and 2 gaskets. I dropped the level of the old electric that was on there and it started pumping again. I'm going to get the spacer for the mechanical and put it on...fingers crossed.

 

[Cardog68]

Locking gas cap

Sorry to switch gears on ya, but can you post the part number for the locking gas cap you got at Napa? I have not had any luck finding a locking cap for my 4/72. Thanks.

Yes, i'm looking into putting a manual back on. I recently drove off with the OEM gas cap sitting on my tire from the gas station and had to buy a generic cap from napa. It is a locking cap with a key....thank this could be the issue?? I also think the pump is even if not higher than the tank....