Engine/Transmission (1998.5 - 2002) Bubles in fuel line

[andrewkoperdak]

I am getting frustrated over air bubbles getting in my fuel gauge line. I am reading my pressure at the inlet to the VE44 from the filter house. I have Geno's banjo installed also. I am not sure if bubbles are getting in there from the VE44 pump or the Xfer pump ( I suspect cavitation is the source). My gauge will read erratic after about 1000 miles. More so when I am at 6000 feet or more. My fix has been to unbolt my pressure sensor and put it as low in the engine compartment as possible. I leave it there for about 30 minutes and this gets the air out. Bolt it all up and I am good for another 1000 miles.

My fuel pressure is good as I have check it with a mechanical gauge. My in-truck gauge is electric and a Westach.

Anyone have a long term solution for this?

 

[Thomas]

I have a Westach dual fuel pressure guage on my model year 2000 Ram. I have the sending units attached to the inlet and outlet of the fuel filter, using Ray's (Geno's) tapped banjo bolts and 18 inch lengths of eighth inch fuel hose. I have zero problems with this setup after 15,xxx miles. I actually tried to fill the lines to the senders with air. I believe the air, being compressable, will safeguard the senders from pulsations in the fuel delivery system. I can't see how air alone is responsible for your problems. After all, you probably use an air filled-line when checking tire pressure. Many posts on this board have reported problems (read destroyed) with senders attached to the injection pump. I think you should try moving the tapped banjo bolt to the outlet of the fuel filter and encouraging air in the line from the banjo bolt to the sender.



Good luck!

 

[andrewkoperdak]

Thomas,

What you say is worth considering. I will see if any other posts have other opionions. If not I will probably move the sensor input this weekend.

Thanks

Andy

 

[15w40]

Akoperdac, you have a leak somewhere between the fuel tank and the lift pump. Cavitation creates small vacuum bubbles that will quickly collapse. If you are seeing bubbles, this is air entering the fuel system.

 

[andrewkoperdak]

15W40,



I would like agree with you but this is the pressurized side of the fuel line. Fuel should be leaking out not air getting in. I have no such leakage. The cavitaion point was more about the VE44. Perhaps tiny air bubbles are coming from there and moving up and into my fuel pressure line. I can't see how it could come from my Xfer pump or filter housing.

Thanks for the input thought. I may relocate my sensor input to see what happens.

Andy

 

[15w40]

The fuel line between the tank and lift pump is always under a slight vacuum. The lift pump is sucking on the fuel line and supplying pressurized fuel to the filter. If there is a pin hole type leak in this line you will not see any fuel spill but as the lift pump “sucks” fuel from the tank, this pin hole will allow air to enter. The air will flow through the lift pump and into the filter. You are tapping the inlet to the VP44 and the air bubbles will show up there in your fuel pressure gauge. I would check the fitting to the inlet side of the lift pump, or maybe the quick connect fitting that is just before the banjo bolt.



Hope this helps and sorry I misspelled your name.