engine trouble last night

[metalminded]

Going to pick this car up and i had just about arrived when i forgot to swap tanks and ran out and rolled to a stop on a side street. I swapped the tank to the front and bled/cranked from the engine bay and got it started up after a couple tries.
Later when i was towing the car home, I was cruising along when the truck seemed to be getting starved for fuel. I was holding the pedal constant but i was losing power. I downshifted to forth gear and put my foot in it a bit and it seemed to clear up. at the next rest area i pulled in to inspect the status of my prefilter thinking i might have clogged it up by running the rear tank empty. Pre-filter had some crud, but over all didnt look bad. I hit the restroom, came out jumped in and the truck fired up.... then died about 4 secs later. tried to fire it up again but it only cranked. I re-bled and cranked it up from the bay and got it to light. On the rest of the ride it seemed ok except i felt like the power was surging slightly as if still being starved.... i haven't messed with it yet today as i am on sunday time, but wanted to get some thoughts, theory's and speculations from the gang.

 

[metalminded]

Ok, finally had a chance to take a look. the truck wouldn't start again ( trying to move into the shade to work) so i re- bled it and got it started and under a tree. It ran ok for about 20 seconds then began running rough. looking around i found that there was tons of air bubbles flooding into my clear pre filter. i am pretty sure this is the problem, however not so sure what is causing it. Only thing i can think is either the pump is leaking air into the system or the supply line is. is this common for these lift pumps ?when i got the truck a few months ago it looked as though the pump had been recently replaced... this however means nothing. anyone got some insight? i want to get this thing running right so i can time it.

thanks ahead of time

 

[icanfixall]

Where are you seeing this air. If its from the mechanical lift pump to the filter then yes. you could have a pump thats been installed wrong. Check the flexible fuel line down near the frame rail and the mechanical pump. Many times that line rots out and leaks air. Remember its on the suction side of the lift pump. Otherwise I would add fuel the the other tank and drive it so see if that is the fix. Then finding out whats pluggin up the other tank supply line is whats needed. Also check your pm's.

 

[metalminded]

Yeah i have a clear "universal" filter before my factory filter. normally the diesel is clear and doesn't move much, if i get the truck running though its bubbling and frothing all around. i ordered another pump... we'll see


this truck is starting to be material for friends jokes its had so many parts changed...

 

[metalminded]

New lift pump is in and the truck still isn't starting. guess i am going to try and bleed the injector lines...

when i bleed it off the valve on the filter housing the fuel surges out then stops then surges out.... is that normal? i cant remember.

what are symptoms of a bad injector pump?

 

[metalminded]

So to recap..

i ran it out of fuel on the rear tank
switched it to the front full tank, held shrader valve and cranked it by jumping the starter it started
about an hour later on the highway it started losing power and stuttering.
pulled off at a rest stop shut it down to inspect and it wouldnt start again. i re-bled it the same way and it started
it got me home but now it doesnt want to start , i did get it to start once but it shut down a few seconds later.
currently stumped and waiting on the rain stopping

 

[icanfixall]

yOUR STILL SUCKING IN AIR SOMEWHERE. tRY THIS. tAKE OFF THE RUBBER FUEL HOSE GOING TO THE MECHANICAL LIFT PUMP. aDD SOME NEW LONGER HOSE SO YOU CAN SUCK FUEL FROM A CAN AT THAT POINT. aNY CAN WILL WORK. a 1 OR 2 GALLON FUEL PLASTIC CAN WILL WORK FINE. wHAT YOUR TRYING TO DO IS REMOVE THE FUEL LINE ALL THE WAY BACK TO THE FUEL TANK AND SUCKING FUEL FROM THE CAN i SUGGESTED TO SUCK FROM. iF THE ENGINE BEGINS TO RUN NORMALLY THEN YOU HAVE FIGURED THE LINE GOING BACK TO THE FUEL TANKS HAS A LEAK OR A RESTRICTION. sIMPLEY BLOWING AIR BACK THEU THE LINE MAY CLEAR IT BUT THAT POSSIBLE CRAP PLUGGING UP THE LINE IS NOW BACK IN THE FUEL TANK. iT WILL BE SUCKED UP AGAIN.. tHE EASY FRONT TANK CAN HAVE THE SENDER REMOVED WITHOUT DROPPING THAT TANK. tHERE YOU CAN BLOW OUT THAT LINE FROM THE LIFT PUMP THRU THE FUEL TANK SWITCHOVER VALVE TO THE GROUND. hOPE THIS HELPS. Sorry but the good wifey left my computer on caps and I don't watch what I'm typing till I'm done. I realy hate her Fin with my computer when she has her own..Damn it anyway...

 

[metalminded]

Thanks for the reply gary, I have been searching the forum and and read somewhere to do this as well. going to go get some diesel and try it. I did check out that line on the frame, i didn t see anything bad though... i'll keep looking

 

[TronDD]

Did you try getting some fuel into the other tank and switching back to that one? I wonder if it's the fuel selection valve or the pickup in that tank.

Tim.

 

[rattleonby]

I like gary's idea of making a hose right off the pump into fresh diesel...eliminates alot of guess work quick. Tron mentioned above a possible half-way sticking selector valve which happened to me this spring. It was doing the same thing as your truck word for word. Do what gary says with the hose off the lift pump into a can and that'll give you your answer.

 

[metalminded]

i am charging batteries right now, i actually put 5 gallons into the rear tank and filled a cup, i am going to try it on the rear tank first then see

 

[texcl]

With my dieswl vw's I would make mini gas tank out of a mason jar and some clear fuel line . if it was still running rough and there were no bubbles visible in the line I knew it was the pump or injection system. if it ran good I knew it was the fuel line back. Most old vw diesels have a clear line from the injection pump to the firewall to pick out air in the fuel supply.

 

[metalminded]

Well after the truck failed to run on the rear tank and ran fine on the jar of fuel I shot some air down the supply line and it "remedied" the problem. I plan to drop the tanks and address this but I would like to address all tank related issues in one go. What should I do in the tanks besides cleaning them out? Parts I should have ready? I have read a little bit about the shower head pick ups breaking. Do I want to replace those or set something else up?

 

[riotwarrior]

Get rid of shower heads would be a good idea...

Not sure what else...

 

[metalminded]

If I eliminate the heads then do I need to extend the pick up lines?