1988 BII Fuel Gremlin

[ldbill39]

I am working on trying to figure out what is going on with my BII, and any help would be appreciated. Last Aug. I started having problems with the gas tank sending unit, and main fuel pump, the fuel pump took a dive and left me 2 miles from home. Towed it home and left it parked by my garage. It sat there until 2 weeks ago when I decided to work on it. I decided to try to start it for kicks, and the damn thing started and ran. I pulled it into the garage and hooked up a fuel pressure tester, it went to 12psi, but started. I kept shutting it off and starting it back up a few times and the pressure gauge went to 40psi. Now, it would think that there is a electrical problem somewhere, but I didn't touch the truck for the 4 months or so it sat by the garage, even had the tow strap on it for that time. I haven't done any thing to it except start it and get the fuel pressure. What do you think?

 

[unoleisu]

From your write up, I get that you left the original fuel pump in place, and did nothing originally except tow it home?

If this is the case, it sounds as if you do have a bad electrical connection.

I would start by checking connections:
1. At the fuel pump relay
2. fuel pump(s)
3. inertia switch (There is a write up in the tech section for full details on this one)
4. ground
5. fusable links at the starter relay

You need to make sure the connectors are clean and not corroded, sand lightly with fine grit paper or equivelant, and use a little di-electric grease on each contact point.

 

[ldbill39]

Electrical

So far that is what the consensus has been so far. But the truck started without anything being touched, so far I've checked the tank plug and the main pump plug, and everything seems to be fine. I am getting good continuity and the power is what it should be. One person said that there could be sediment in the pump and that could be causing a blockage. My current thought is to change out the pump, as I can't check the the connections in side of the pump. There could be a dead spot in the connections within the pump. That could be why it only comes up to 10psi on the first key turn. Unbelievably it does start at 10psi, but then goes up to 38-40psi. I think I am going to put the front up on jack stands, to simulate a hill, and see what happens then. Otherwise I feel like I'm beating my head against a wall.

 

[TexCaliBII]

Got something similar on my 88. In my case it will not start after being left out overnight in the cold. Push it into the garage and the next morning will start just fine I think it is the intank pump in my case because I get the same kind of readings you do too. I'm ordering an intank pump/sending unit from Rockauto when the funds are available and hoping that fixes my issue.

 

[ldbill39]

Flat spot on pump

I talk with a Ford mechanic this afternoon, and he agreed with me that there is probably a flat spot on the motor that is in the frame rails, the main pump, as this was something that he had seen before. As the pump wears, the brushes will sometimes wear through the copper commutator and cause the flat spot, this is new to me, as I have never had a pump do this. Either they work as specified, or they are just pretty much dead. So I guess I will be changing out both pumps to be on the safe side.

 

[ldbill39]

Water in system?

AlaskaBII, have you checked your system for water? Drop a bottle of Heet in the tank and run it, when you refill the tank, add another bottle. It sounds like you could have water trapped in you main pump.

 

[TexCaliBII]

Yeah,
I have a thread on here that documents my (mis)adventure with this truck. Still working the issue with it when I get the time/money, etc....

 

[headhunter257]

i know your problem under the passenger seat theirs a black box with a red dot on top rip that dam thing out and hot wire it together its the roll over switch happend to are bronco 2 and we replaced everything and the dam thing doesnt work when you roll over the truck cuz i put a new one back in befor i went camping i still rolled over the dam truck and it did not shut off

 

[HndMeDnBroncoII]

its cause that switch is designed for crashes not roll over if the truck is hit hard enough that switch will pop up and shutdown the pumps
just sayin.