Subford
Found out what problem was . previous owner had two of the electrical plugs over top of radiator switched . You would think ford motor company would have it where no too harness connectors could not be interchanged .I wanted to thank you for all you're help on it. It runs like a 460 with 36k miles should now. Again thank you

 

Hi, when I turn key on pump runs for 1 second then stops. Pressure gauge at rail sometimes shows around 10psi after cranking several times. Will randomly start and pressure climbs very slowly to 35 and will idle fine, sometimes for 20 minutes, sometimes for 2 minutes, then pressure will drop to below 10 and dies. If turned off with good pressure will hold for hours. Any thoughts would be appreciated.
Thanx

 

Bad fuel pump.
Do you have two tanks?
If so does the other one work?

 

Thanx subford.
There is only one tank, I believe 55 gal. It has two fuel pumps, one in tank, one on frame rail. I changed fuel filter. Do you think it's the in tank pump? Could they both be bad? Yesterday I also noticed batt not charging. No output from alt. is there a fuse? Was working two days ago.
Thanx for the help

 

My guess would be a bad tank pump.
Is this an Van or RV?
No fuses for charging. But you do have fuse links at the starter relay for charging.
Do you have an external voltage regulator? If so make sure it is grounded.

 

Thanx again subford.
It's an rv. I'm going to drop the tank today and check it out. Ill report back.
Thanx

 

Fuel issue solved. It was the in tank pump, it was shorted out. Dropped a new one in and all is well.

Still have the alternator issue. battery wont charge, there is a red wire, and a orange/white little one. The red heavy gauge wire has 9v coming off of it at idle. I checked all connections in and around battery, all seems well. how do i tell if i have
the external rec?

 

Sounds like someone has done some re-wiring. Those are not Ford colors for the external regulator or with an regulator build into the alternator.

 

Thanks again sub ford.
I just found the external reg its next to the headlight , white plastic box. There is also a relay next to it attached to the inside sheet metal that has lots of corrosion on the contacts. So I replaced it, and still no charge from alt. I guess I have to test the regulator next?

 

Make sure the regulator case is grounded.

1990 External regulator Alternator:


/

 

all fuseable links good. All grounds cleaned, including regulator case. Still not charging. IS there a way to ohm out the regulator?

 

The "I" terminal needs to have voltage on it for the alternator to charge. It should be a light green wire with a red stripe. But you did not note that color wire above.
So check the "I" terminal for power with the key on. If no power at that point you need to find out why.

 

[QUOTE=subford;15486681]Make sure the regulator case is grounded.

1990 External regulator Alternator:


it was the terminals on the voltage regulator plug. They were heavily corroded, had to file away the scale. All good now 14.3 at idle. Sub ford thank you for your help.

 

My RV would give me trouble like that sometimes. There is a pigtail attached to my fuel pump fuse. If that pigtail lost connection the fuel pump fuse would blow. I tracked down the right piece made to attach to glass fuses and the problem was solved

 

Ok, i have a four winds class c motor home on a 1991 e-350 cutaway chassis with the 7.5 liter efi engine with 75000 miles. I bought the rv from my landlord, he said it ran fine until he thought the fuel pump in the tank went out. It was parked in his yard where he decided to have a carport built, he needed to move it so the builders would have room to work, he started it ran fine and backed it up about 40 feet from its original location, and it never started again, it turns over but does not crank unless i use starting fluid, ok thats the back story, this is what i have done to it:
It only has one tank, i replaced the in tank pump
i replaced the pump on the frame
i replaced the fuel tank
i replaced the fuel pressure regulator
i had the computer rebuilt
i replaced the ignition control module
i replaced fuel pump relay and fuel injection relay.
i have tested the injectors, with key on red wire shows constant power as it should
i have tested for injector pulse while turning the engine over and the injectors have pulse
both fuel pumps operate as they should
the engine is also getting spark as it should
with all this done it still only turns over no crank unless i use starting fluid then dies when starting fluid is consumed
i have also checked the inertia switch it operates as it should
all fuses in fuse panel are good
oh and the cel does come on when key is on
PLEASE someone help me before i burn it to the ground!!!!!!