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FI pump won't prime on new install

John N

John N

Addicted....Ex-SOA VP
Lifetime Member
SOA Member
City
Rockville
State
VA
I got eveything installed. It all looks right. I've reviewed the instructions. I got fuel in the line up to the FI fuel filter (had to suck on the line to get it there) which is right before the pump. The gas tank is half full. I've had the line off at the TBI (this is a Howell system on a 360) trying to get it prime. The pump cycles for about 3 seconds at a time, then stops. I've been trying it repeatedly. I've sucked on the line at the TBI. I can't get gas to go through the pump or get it to start pumping. All parts are new. Any ideas/ help??? Thanks. I really want to get this thing running.:confused:
 
The only thing that comes to mind is bench testing it with a few feet of hose to make sure your pump is providing output. Just because the pump motor is running doesn't mean the wet side of the pump is operating.

As far as the motor cutting off after three seconds...that's computer controlled and should happen immediately after every time the key is placed in the "run" position until a certain amount of backpressure registers.

If your pump runs and you have no pressure at the fuel pressure regulator (FPR), then you have a bad pump, leak or occlusion prior to the FPR.

If it's running and you're getting pressure to the FPR and it's stopping, check the return side of the FPR. An occlusion can back up the FPR and in turn, the supply line.

If it's running and you have no pressure at all after the FPR, then you have a bad FPR.

HTH.
 
Whooops!

I just noticed something. You have a puller pump (versus a pusher or in-tank pump). Make sure you have petro in the pump. Most pumps won't draw fluid through the resistance of a small diameter line without being fully primed.

Try using a dropper or small fabricated funnel, using gravity to fill the pump, then syphon the line running to the pump again and attach.

HTH
 
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Where is your pump mounted? if you are using a Walbro or similar pump you may need to relocate it to a lower mounting position for correct siphon action to occur. The FI pumps do not pull fuel from the tanks very well, they are design as pushers only. I mounted my pump right in front of the tank on that crossmember, but I also mounted a regular Carter style high volume pump in front of it to serve as a booster pump. Worked like a champ and never had a moments problem for the 5 years it was installed. Have since gone to a fuel cell where the back seat used to be and the pump is mount below the tank ensuring gravity feed into the suction side all the time. One other thing you can do is temporarily hot wire the pump to run all the time to get the lines primed up. Just wire it up so it runs and quickly apply some air pressure to the tank through the filler by wrapping a shop rag to get a good seal around the air chuck. You will know you have fuel prressure when the pump slows down audibly with a reduction in RPM within the pump. Once you get a prime, reconnect the pump to the ECU and start the engine.

good luck
 
ANY LUCK JOHN?

John,here is another thought,if you look at your manual,you can put a jumper across two of the pins on your plug that plugs into the fuel pump relay,when you turn the key on it will run,so be carefull,make sure you have your fuel line routed into a gas jug,make sure the gas cap is loose and the tank can breath,then turn on the key and see if your getting fuel through the line,if not,then try the air pressure method mentioned above,or get a cheap electic pump from your local auto parts place and put in line in between the tank and your FI pump,wire it and then turn the key on,this should push your fuel into the new pump to prime it,just be very careful since you are working with gasoline!-JC:eek:
 
John I had a similiar problem on a system I installed at work. I ended up dropping the tank to find that the pump had sucked the old cj gas sock down,creating a restiction so it wouldn't get gas to the pump. I don't know if that will help you any though.
 
Check to see if you have the wires correct on the pump because it will run backwards-

been there
scramcraz
 
I'm going to hotwire the pump tonight and see what happens. I've been plowing ice/snow for 2 days and haven't had a chance to try again. I quit plowing at about 5 today, that ice is too hard on the plow and truck. It's supposed to get above freezing tomorrow, maybe it will soften up and I'll move some more. And maybe get the Scrambler running :D .
 
Murphy's Laws continue to prevail. I got the fuel pump primed. Fuel to the TBI, can hear it going in the return line. Still won't start. I have it down to 2 possibilities or both. My Optima battery (this is my second one) is only putting out 11.81 volts and drops to 9.something cranking. The other, my tach stopped stopped working a while back, I figured it went bad or the MSD adapter croaked, now I figure the MSD tach output is bad. That would make it so the ECU would get no signal to pulse the injector. So, I already ordered a new MSD from Summit, 2nd day delivery, and I'll take the Optima and get it replaced tomorrow.
 
right track

John sounds like since you have the pump primed now and it still won't start i think you maybe on the right track,with the voltage and the tach signal,since your tach is not working your tach output may very well be bad-good luck and keep us posted-JC
 
Still trying........

Not YET:mad: . I put on the new MSD Off Road, I do think I needed it. I can see the injectors pulsing a little fuel now and then. I charged the battery, probably need to do it again. AND now the fuel pump lost it's prime again. I'm going to put more gas in the tank tomorrow, maybe that will help the pump get the gas flowing. If this doesn't get it going, does anyone know the part #'s to get a replacement at Autozone or the like , cause I don't want to wait for Howell to send me another (they will, but I don't want to wait to get running and I'll have a spare).
 
put a 1amp trickle charger on the Optima and let it sit for as long as you can (over night is a minimum). i had a similar problem with a new optima i bought. after letting it charge this way for a couple days, it was 10x better.

you can pick up a 1amp trickle charger from AutoZone for less than $20. i found a regular battery charger wouldn't charge it properly...don't know why.
 
IT'S ALIVE AGAIN!

Finally!!!! It's alive again. I got it running this afternoon, runs pretty smooth, too. One of my hidden problems was a loose fuel fitting on the new lines I put in, it was allowing the pump to get air instead of fuel. D#$% tach still doesn't work. New seats go in tonight.
 
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