Loss of engine power

[Skip426]

Originally Posted by SafetyFirst

We have a 2007 Holiday Rambler with the 325 HP ISB Cummings. We had that loss of power problem on Interstate 25 north of Denver recently. A Camping World just happened to be at the next exit and when they pulled the filters they were both almost empty. A check of the low pressure fuel pump said it was running but not pumping fuel so they replaced it with a new one and after 500 miles going home every thing seems to be working as it should. With only 33000 miles on the unit I was very surprised to have this problem. I had changed the filters before leaving on vacation and everything seemed fine, the old filters were full of diesel.

The electric lift pump on the Cummins ISB engines is in a poor place to say the least. Electric pumps push fuel better than they can pull it , and they don't like heat and vibration. Dodge trucks with the ISB, both with the VP-44 injection pump and the HPCR fuel systems , had repeat failures in many cases , until it was finally decided to move the lift pumps into the fuel tank ; same as the gas engines . This was a production line change in new trucks sometime in 2005 if memory serves and then retro fit kits , to move the pumps became available, on older trucks as their pumps failed.

[jleamo1]

Originally Posted by Happycarz

Oops! Just getting back to this thread.

I am in the process of installing the Fass before the lift pump. I am taking the lines off the primary fuel filter and attaching to the Fass. I left the secondary filter in place.


2008 Monaco Camelot 40' PDQ

Harry, don't send pressurized fuel through the factory lift pump, bypass it and send it from the 1st filter directly to the 2nd and cap the old lines. Not sure if its true but Cummins told me if you send pressurized fuel to the existing lift pump it will fail and the check valve that is built into the pump may become stuck and block fuel flow.