foamy fuel

[4inchsnappy]

My wife was driving our 95 k2500 6.5 suburban, she heard the belt squak, the tach was jumping around, the volts(which has never showed above 14) was just above the 9. She stalled, could not restart. I've installed new batteries, and will do the battery cables and a new belt tensioner next, but I thought the truck would start with fresh batteries it did not. Sooo my thought is the low voltage affected the lift pump and the IP starved for fuel airlocked. I cracked into fuel line after LP before the IP. I jumped the stock LP it pumps but it seems like I'm gettting air/foamy fuel not a steady stream, I have 20 gallons in the tank. Also put in new fuel filter and purged the air out of top bleeder 3 times still after cranking I open filter bleeder I get puff of air.

Whats up?

[DmaxMaverick]

Sounds like you have a leak between the LP and tank. Try applying low shop air pressure (less than 5 PSI) to the tank and watch for leaks. If you get no external leaks, it is likely the sender/pickup inside the tank. They can corrode or break. It sounds like yours is either at the fuel level, or it broke while your wife was driving it. Blame it on her, since she was driving it at the time. That's what I do:D

It could also be a plugged pickup sock, but doesn't sound like it. There is (on most models) a valve in the tube that opens if the restriction is too great, but it should be near the 1/4 tank level. 20 gallons should put the level well above that.

[Warren96]

Do you have the smell of fuel from your truck when you get near it?Mine had a fuel line rust thru and would pull air into the suction line.It didnt leak onto the ground but you could smell it when you got close. Tell your wife the fuel line rusted because she was driving it! HA!

[brianblack138]

while your at it. Make sure your battery cables and grounds are all tight. I had a similar problem where they worked loose. Make sure to blame your wife since she was driving.

[4inchsnappy]

thanks for the replies, I will of course continue to point the finger of blame in her direction. the truck never breaks when I'm driving. I will try the sugestions to find the source of air infiltration, I've never had to drop a tank before to get to the sending unit, this sounds like a lot of work.

Also I've hear there are 3 main grounds where are they? and where is my OPS located?

[farmboy1989]

OPS is located just below the fuel filter at the back of the intake manifold. Working on the ops on my 94 3500 right now.

[DaveNY]

YEP! Truck runnin lousey, blamin the old lady and sleepin on the couch, my three most favorite things.

[DmaxMaverick]

YEP! Truck runnin lousey, blamin the old lady and sleepin on the couch, my three most favorite things.

You are most definately in the right place, then. What a group.

[tommac95]

Good chance your tank, pickup, and lines are all on their 'last legs' ; there are advantages (simply that one may not have to do again) of replacing all those and the brake line along the frame rail simultaneously [i did].

The most intensely rusted portion on mine was the pickup's fuel lines from tank to hose segments connecting to frame-rail tubes.

Of course, great effort should be expended in ruling out this as the cause of the problem, as it implies a miserable solution !

[4inchsnappy]

I've put a clear section of tubing between fuel tank and LP. when i put 12v to the pump I see all these great little air bubbles @#F%&!. Thanks for the idea to change break lines while the tank is down and out of he way....I still blame the Mrs. and yes the couch is quite comfortable.