How long does your lift pump run?

[mikel]

On my last truck the lift pump would run about 10 seconds or so when I first turned the key on to start the engine, but on the one I have now the pump will only run about 1-2 seconds. Can anyone with an '01 ETH confirm if this is normal? It seems like the pump should run a little longer. I also noticed that last evening while I was getting fuel, I tried to drain any water out of the filter housing but nothing came out. Shouldn't this drain when the engine is off? BTW the engine and lift pump are stock (for now ).



Thanks,

Mike

 

[Ramboy]

Mike,

I have a '99 and it only runs for about 2 seconds. Since it is pressurizing the system, I would be concerned if it ran any longer.

Phil

 

[Michael Hughes]

I can hear mine any where from 2 to 5 seconds.

 

[Cliffman]

2 to 5 10/4

 

[MidwestMotorman]

Be concerned

Sounds like it is time for a fuel pressure gauge. Mine to to run 2 to 5 seconds, it was bad, and it finally went out. My new pump runs for half a second. Get a gauge or be prepared to walk.

 

[Cliffman]

Gauge

The ole lift pump is on a constant monitoring system via the SPA gauge . 12psi at idle and 11psi at cruising speed and no less than 6psi at WOT pushing 400hp . We're on pump #2. 1st pump went out at 40,000 . Good thing I had the ole backup in the trunk. This pump is supposed to be the revised one from Cummings that wont fail. We'll see!

 

[big barney]

Mine never runs on start up, it never has. I have 13 lbs of pressure at idle and I have never seen it below 10 at wot. Dont know if I have a faulty pump or not. The truck runs great and I have no problem starting after a filter change. The pump will run about 20 to 25 seconds after bumping the starter. I hear all you guys saying that your pump runs a little before start up. Wonder why mine never does?

 

[MCummings]

My old list pump would run for about 5 seconds with Key-on.

The old lift pump would hold a good steady 1PSI at idle, with a full tank of Diesel.



My new pump, replaced under warrenty about 2. 5 months ago, runs for about 1/8 of a second, or less, it's just a blip, and pegs out my 0-15PSI guage (with key-on)

Idle I get 14. 5PSI with the Low Fuel Light on, and nearly 15PSI with a full tank.



MerrickNJr

 

[mikel]

Thanks for the replies

Thanks for all the replies and advice. I do have a pressure guage at the house that I'll stick on the truck and see how pressures look, but it's not a permanent one that I can leave on. The truck runs fine and gets better mileage with more power than the '99 it replaced.





Thanks again,

Mike

 

[rashwor]

Lift pump run time.

I have a '99 (ETC 5-speed) Ram 3500. At 82,000 lift pump was changed out. The original lift pump would run 1 - 2 seconds with key-on. The replacement pump runs only about 1/2 second at key-on and does not appear (I cannot hear it running) when I bump the starter, but do not allow the truck to crank. I am thinking that the new pump pumps to a certain pressure is obtained and cuts off at that point (can anyone confirm this?? ). The new pump that was put on my truck is supposed to be the new design.

 

[MidwestMotorman]

answers, i think...

rashwor---I think the pump just runs until a certain amount of load is placed against it , and then shuts off. It is hard to tell, the pump works just as the key is turned on, as it pumps up pressure fast.



big barney---It could be that your pump has a really tight fitting check ball that does not let the pressure bleed back. You are supposed to hear the pump buzz a little just as the key is turn to IGN. Maybe you just do not hear it.



Sometimes the failing pump will kill the injection pump after a while. I found out my lift pump went out after I changed the fuel filter and it would not prime. I put on a fuel pressure gauge and I actually had a vacuum, 3", so I knew that the VP44 must still be good. The pump is designed to suck fuel if need be, so everything was still working fine.

 

[chuck3]

Lift Pump.

Mine runs 2 to 5 sec. always has to the best of my memory.

 

[Ron Bissett]

If you have a gauge watch as key is turned to ,Run position Pump has two run setings one at start before start (run position) one or so seconds . Two a continual pump, if eng starts, or 25 sec to 26 sec if eng not running(as in bumping the starter to prime filter after change. Also depends location of fuel pick up before or after filter as to PSI . Most post do not state this ,some have two pick up and two senders or two gauges. Looks like the new pumps put out more, but don't know how they are set up, befor or after . I get 9,Psi run position, and 8 to 11Psi and 4to 5Psi wot ,with my pick up after filter . I will get a second sender soon ,with a switch . Just for information , Ron in Louisville KY

 

[DHawthorne]

Only hear mine after I change my fuel filter. Use to hear it all the time when it was new until I changed my first fuel filter. AFter that, never hear it again until the filter is changed. Based on what I known about fuel systems I think mine had a air leak on the supply side and lost pressure when parked.



Dave

 

[Skunk]

Does anyone who has changed to the new pump notice that they're quieter? Maybe it's just me, but I have to strain to hear it now. It also has about the same running time - 4 or 5 seconds.

 

[MidwestMotorman]

short timer

Skunk---My pump is the new part number and it only runs about a third of a second. I know my system is airtight and has no bleed back.

 

[Ron Bissett]

Originally posted by big barney

Mine never runs on start up, it never has. I have 13 lbs of pressure at idle and I have never seen it below 10 at wot. Dont know if I have a faulty pump or not. The truck runs great and I have no problem starting after a filter change. The pump will run about 20 to 25 seconds after bumping the starter. I hear all you guys saying that your pump runs a little before start up. Wonder why mine never does?

Try putting key in run position as you watch pointer of gauge see if it will move to high point of idle and then drop back to zero ,this is if is working this is without starting eng. or bumping starter. Ron in Louisville KY

 

[FAB]

lift pump

Lift pump run time is controled by the ECM. It runs for a predetermined time (approx 1 sec. on my truck) then shuts off. When you 'bump' the starter without starting, the ECM will let the pump run 15-30sec. then shut off because of the lack of a tach. signal. The pump pressure is controled by a mechanical means; spring controled by-pass valve that vents back to the fuel tank.

 

[rashwor]

Lift pump run time

On the contrary. My new pump is louder. Shorter run time at key-on, but definitely louder.

 

[JJMiller]

Mine runs for a few seconds when the key is first turned to "on". I've noticed that it shuts off the same time as the wait-to-start light goes off (non grid heater season only).



It looks like the ECM wants you to wait until the fuel system has been primed before you start it up.



--J