Hi All,
I have a intercooled 91 W250 manual trans, 4wd.
The truck was running fine until I parked it for 4 months while I was traveling.
When I got back I checked all the fluids before starting it, and noticed that my add-on racor housing was mostly empty. It is an old FE500 installed in the rubber line between the steel line and the lift/transfer pump. I changed the filter, filled it up, bled everything and it fired up nicely. I ran the truck for about half an hour and then shut it down. A couple hours later I took it out, and noticed it seemed to be lacking power on the first big hill. Next big hill after a short stop it lost all power and started blowing white smoke, just crested the hill, and it died. Bled the injectors and it started right up again. Been doing that for a couple days now. After I bleed it, it will run for a bit, but if I load it up, or rev it, it blows a ton of white smoke, misses, loses power and dies. when I bleed it there doesn't seem to be any air in the filter, but lots in the injector lines. I bypassed my racor, since I have had trouble with it before, with no improvement. If anything it seems to be getting worse. I also put a piece of clear line between the steel lines and the lift pump, and I can see some tiny bubbles, but not much, and it doesn't seem to be accumulating in the filter. When I pulled the line off the (diaphragm style) transfer pump it seemed to hold a vacuum when I pumped it with my finger over the intake, and I seem to be getting good flow when I pump it by hand with the filter bleed open, but when I cracked the filter bleed nut with the engine idling it sucked air and the engine bogged down. I also put in a bunch of Howes and STP diesel treatment, with no effect.
Any suggestions would be greatly appreciated!
Eli

 

Following up on the low fuel pressure I discovered my filter was totally plugged. With the Racor in there I hadn't even thought of it.
I feel a bit silly for missing it, but sure glad it's running!