I have an 88 250 3/4 ton 5.8l truck. I hav put an extenal fuel pump on to insure function. Have fuel to intake. Charcoal box gone. Flooded at first fuel. Pumpwill run 42 psi constant. When i turn the pump on it floods the manifold. How do i stop this.?

 

Welcome to the forums.

Just wondering.....this truck is fuel injected, correct?

 

Yes efi 5.8 2wheeldrive. Daul tank . high low?

 

You put a gauge at the regulator and it reads 42 psi? Or the pump is rated at 42 psi?

You say the manifold is flooded? Exactly how do you know this? When you try to start it there is black smoke? Or does it foul the plugs and not run?

What were the circumstances that started all this?

 

I just bought the truck. I have been trying 2 get fuel to engine. Bought external pump for sanity. Had pulled air induction to replace fuel lines 2manifold. Rotten.afterwards. for giggles i cranked up the pump and the 2 fuel lines going to the manifold just ran. Lucky i guess. Now i know the motor runs but need to remedy the flood. The guy i got it from said a real wrench (not a backyard)told him relay or pump. So i took a short cut. Bad?

 

Ok, you replaced the two lines? From where? These trucks have a unique fuel system due to the dual tank and the switch valve on the frame under the drivers seat. You say the fuel just runs? Meaning the lines weren't hooked up to anything and fuel just ran out of them?

 

The 2 lines ran in a cluster from vapor can 2 manifold. I replaced them due to rot. The only thing i changed was to bi pass vapor can. It just overflowed when in line and fuel was put to it.

 

This truck was used on a ranch so this isnt factory work done. Some ol boy just kept it running till now. I love this truck and want to get her going like it deserves. So. Im nuts. Somebody has to do it. Thanx so much.

 

The vapor canister does not get actual fuel through it. Not sure what got hooked up, but that little box on the front inner fender doesn't get hooked up to fuel pressure.

Got any pictures?

 

Give me a min.plz.

 

Main fuel feed
This is the 2 hoses i replaced (rt) mainfuel lft
Fender well pass. Side.

 

Those are fuel vent lines. The two fuel lines(pressure and return) go into the back of the manifold where they attach to fuel rails(and the regulator). They are hard plastic lines.

If you are getting actual fuel there, then something is wrong.

Crawl under the truck, look at the inside of the frame, under the seat area. You should see the selector valve and the pump then the line going up the firewall to the fuel rail/regulator.
(I just googled a picture)

The two lines on the RIGHT side are the feed/return. Large one feed, small one return.

 

Sorry correcting dumb. Vacum lines go?

 

I'm sorry, but you have me really confused now.

We were dealing with fuel coming out of the lines you show in your pictures?