Anyone with fuel pump and system knowledge live within a couple of hours of St Augustine Fl? My truck is a 93 W250
5Spd, POD'S,upgraded compressor housing and turbo. 4inch exhaust AFE intake, tweaked pump. Truck was making about 40 lbs of boost. now it is making about 15
I pressurized the system and found no leaks. I used to run veggie in it. I thought maybe something was clogged. I have been running and lot of additives and changing filters to no avail. I'm not very mechanically inclined, so it's hard for me to do stuff to my truck. I would be willing to drive if someone could help. Thanks alot guys, Alex

 

i would pull the dipstick and smell the oil... see if you it's overfilled and smells like diesel fuel. the lift pump may not be doing it's job... even from a distance the guys on here can be VERY helpful and aren't gonna talk down to you if you need something explained. you've checked the right things so far, just need to keep looking, the stock lift pump isn't very excpensive and may be worth replacing to see if it helps.

 

Is it smoking more than usual? Check the shaft play on the turbo.

 

The truck had a new lift pump a couple months ago. It still smokes about the same. Not sure what shaft play is. I appreciate all you guys responses, Alex
I'll check the oil today when I get off work and get back to y'all

 

Pull your intake tube off the front of the turbo. See if you can wiggle the turbine wheel that you will see inside the turbo. If it moves side to side or back and forth, that is shaft play.

 

Could it be a blown headgasket? 40lbs seems like alot!

Jon

 

Fuel guide pin could be stuck. I've had this happen to me before twice after doing some pump tweeks. Confused me for a little while before I figured out it was the guide pin. Boost went from 27 max right down to 14 max.

Have you tweeked with the injection pump at all, or will you need instructions? (Checking the operation of the guide pin takes about 5 minutes, and alot cheaper than buying a lift pump that may not be required).

 

Hey there I live in Gainesville not too far from you. I have almost the same setup but with a 1992. I may be able to take a look at it

Jim

 

If you check the shaft play in the turbo, you should have very little side to side (not enough to make the wheel hit the housing) and none in/out.

 

The side to side shaft play can be as much as .012" If memory serves me right. Just make sure you can't get the blades of the turbo to drag on the housing. These turbo's have a compound floating bronze bearing and use lots of oil flow to keep things cool so they will have a lot of play under normal circumstances. But is the play gets to large then the blades can touch the housing which is very bad news. If your intake side doesn't drag then your exhause side could still be dragging. It's harder to check that however.

Does your turbo have a waste gate? Check to make sure it isn't stuck in the open position. Otherwise you have a fuel problem or possibly a cloggen air filter. Have you checked that?

Also, is it possible you have a leak in your boost gauge line or the gauge has gone bad. You didn't say if you have lost power.

Edwin

 

I think you've got the right idea. Also check to make sure the AFC tube isn't broken.

 

Thanks guys, sorry about the delay in writing. I have been really busy at work and haven't had a chance to look at it. probably won't be till the weekend. I really appreciate all the advice from everyone, Alex