4BTA dies after 1 hour run

[vssman]

Hey guys,



New to the TDR and have a question that some of you 1st gen guys may be able to answer.



I have a 4BTA in a streetsweeper that will run good for about 1 hour then sputters and dies. The engine and injection pump looks just like a 89-93 6BTA except for 2 fewer cylinders. To restart it I have to crack #1 injector and let out all of the air bubbles. So far, I've replaced the pusher pump, hoses, filters and even swapped the pickup tube with the return tube in the tank (They both go to the bottom of the tank) without any luck. Any ideas?

 

[moparguy]

Well, cracking the injector to restart kinda kills my best guess. That would be a plugged fuel tank vent opening.



Little bro replaced the fuel cap on one of his tractors, afterwards it would run for a while, then shut down. Finally figured out that the new cap didn't have a vent hole



Good luck, Ronnie



BHMF, . Welcome to the TDR.

 

[fox]

my step van went thru this same deal. After dropping the tank to look for obstructions we found bacteria on the sock. Cleaned it and added some biocide and she has been fine for 10 months.

The lift pump can't draw fuel thru the sock.

 

[LarryB]

My guess would be a leak in the suction line along with restricted flow in the tank, causing it to suck air. Course it could also be seals in the VE pump. Try putting in a clear section of fuel line just before the pump. That way you can watch for bubbles/air. Older VWs using the 4cyl VE have this.