Lift Pump?

[cudaaa]

I have a bad lift pump. Is one brand better than the next. Or are they all about the same. Thanks cudaaa

[sidedump]

All about the same.
Napa brand was the way I went last time. Their parts and service always impress me.

[markrinker]

Cudaa -

What were the symptoms? Did your truck stall completely, or just run badly?

[cudaaa]

Mark it has some hesitation about 3/4 throttle. Not all the time but more and more frequent. I changed fuel filter. did not help. This started before I put on heaths 2.0 chip and other upgrades. Now after the upgrades the problems are worse. I think because it wants more fuel.Cudaaa

[DmaxMaverick]

Before you go shopping for a pump, make sure it's the pump than needs replacing. It could be something else much less expensive and easier to replace, like the OPS. On a '95, the check is simple and you can do it yourself.

Set E-brake. Place end of water drain hose into suitable container and open drain valve fully. Place container in a position you can see from the driver's seat, if you can. Turn key to "on", but do not crank. Place gear selector in any position other than P or N. Turn key to start for about 5 seconds. The engine should not crank (if it does, you have other problems). The fuel pump, if working, should pump fuel into the container, and you should hear the pump. This process by-passes the OPS for the start cycle. If the pump pumps, check the fuel pressure. You can plug a gage right into the drain hose. It should be above 4 psi. If you have flow and pressure, and voltage to the pump, the problem is elsewhere, likely the OPS, which fails more often than pumps.

As far as the quality of the pumps, I have found no one better than any other. Napa is a good source, as stated above. Autozone also has good pumps. The dealer, IMO, has nothing special.

[whatnot]

US Diesel Parts was the cheapest I could find. It was about $50

USdiesel (http://www.thedieselpage.com/vendors/gomers.htm)

[cudaaa]

Dmax Thanks for the help! It was the ops I also installed a relay to take the load of the fuel pump so the ops wont have to. Thanks again! Cudaaa :D :D

[MEdlin]

Ok, what and where is the OPS?

[CleviteKid]

I can answer half your question :confused: .

OPS = Oil Pressure Switch. It will shut off the lift pump if you loose oil pressure (like when the engine stops or stalls) as a safety precaution.

Not sure where it is on stock trucks - mine is somewhat modified. Maybe it is near the back of the engine, behind the intake manifold, between the heads. There is a drilled and tapped passage there for oil pressure gauges and the like. Maybe the trucks newer than mine used that same feed for the OPS. I am SURE I will be corrected if I guessed wrong. tongue.gif

Dr. Lee :cool:

[charliepeterson]

Try looking just behind the fuel filter housing bracket, in the valley on the driver's side.

It's much easier to access it if the fuel filter support bracket is moved to the side.

The OPS is long and skinny with a three wire circut.

[MEdlin]

Great, I'm going to check this before buying a Lift Pump. I did read about the Lift Pump receiving power from two circuits, the ignition switch in Crank position and the oil sending unit. I just didn't catch on to the OPS acronym.

Thanks much!

[C.K. Piquup]

I stay with the OEM lift-pump.There is nothing wrong with the quality,in fact,I think yhey are best.The stock wiring just is hard on all pumps.

[aj neireiter]

still new with all of this, but I'm catching on. Where is the water drain hose, and the drain valve?

[cudaaa]

Should be on the T-stat housing. Small t valve.
Hope this helps. cudaaa

[moondoggie]

Good Day!

I never guess about lift pump function, I test. On my trucks it's easy.

I hook up a pressure gauge to the vent port on the top of the fuel filter, crack the port open, then do two tests. 1) Put tranny in anything except park or neutral & turn key to crank. Engine won't crank, but lift pump will run. 2) Put truck in park & start. I see 4 PSI or so either way.

I then remove the pressure gauge & run a rubber hose from the vent port on the top of the fuel filter to a container, & repeat 1) & 2) above

[faughtj]

Being pretty new to this, can I ask what type of pressure gauge you use for this test, and where it can be purchased? I have a 95 3500 6.5TD that is low on power, so I'd like to check this pressure as I am getting frustrated with the lack of power that it used to have. Thanks!

[cudaaa]

faughtj Give heath diesel a shot. He sells a good gage kit. I think its under 50 bucks. Bill might have some other ideas. Bill is a great guy to wook with. cudaaa

[moondoggie]

Good Day!

I used an old vacuum/pressure gauge I had laying around from when they were used for troubleshooting engines. It's adequate: the lift pump will only generate a few PSI anyway.

If I didn't have a pressure gauge, I'd just do the parts of the test where you check for flow. Believe me, if you have adequate flow, you'll know it. Even with the engine idling, it comes out the hose pretty good. If it's doing that, it's unlikely there's anything wrong with the lift pump system.

Blessings!

Brian Johnson, #5044