Are these bubbles caused by vibration or an air leak?

linx310 · Post by **linx310** » Tue Sep 01, 2009 8:22 pm

I put a clear piece of fuel line between the pump and the fuel shut off valve and filmed it.

Are these bubbles normal?

http://www.youtube.com/watch?v=nVRS-vkr1k4

OKCM38CDN · Post by **OKCM38CDN** » Tue Sep 01, 2009 8:27 pm

I would say you have a leak somewhere or your pickup is not close enough to the bottom of the tank... you are pulling too much air...

linx310 · Post by **linx310** » Tue Sep 01, 2009 8:58 pm

I would say you have a leak somewhere or your pickup is not close enough to the bottom of the tank... you are pulling too much air...

I just redid the entire tank and the pick up looked normal.

I disconnected the fuel line from the pickup and tomorrow when I get some help i am going to put soap water along the fuel lines as some one pressurizes them with air.

Post by **wesk** » Tue Sep 01, 2009 11:48 pm

The hidden culprit that lets air sneak into the gas line is the pickup tube in the tank. As the gas level drops and if the tube is corroded and pitted the air in the tank will get sucked into the feed tube.

linx310 · Post by **linx310** » Wed Sep 02, 2009 7:08 am

If it is just the pickup line is it possible just to replace the tube portion of the pickup or do i have to replace the whole assembly?

Post by **wesk** » Wed Sep 02, 2009 5:22 pm

Pull your pickup and filter assembly out first and inspect it. If it has a lot of rusted through holes try fabricating a re[lacement tube.

linx310 · Post by **linx310** » Wed Sep 02, 2009 8:28 pm

Ok I think i may have fixed it.

First I disconnect the fuel line from the tank and pressurized it with my compressor with the fuel valve shut to off.

I coated the entire fuel line in soapy water while my brother would hit it with compressed air as i moved down the line.

No leaks found.

So I removed the pickup from the tank. Submerged it under some water, plugged one end, and then add some compressed air. No bubbles escaped from the tube.

So I reinstalled the pickup plate, attached a fitting with a clear hose that ran from the pickup to the pump skipping the existing fuel lines.

Started the jeep and was getting air bubbles.

Since I knew it wasn't the pickup tube I removed the fitting and wrapped it in plumbers tape and torqued it down.

Started it again and surprise, the air bubbles went away!

So I connected the pickup to the existing fuel lines and added some plumbers tape to the connection and torqued it down tight.

Started it up and almost no air bubbles.

I am hoping this fixes the problem, gonna try and take it for test drive tomorrow.