Looking for a decent mechanical lift pump

[SCHMITTY]

I've been using a stock style lift pump with a 140 gph eBay special feeding it. It finally died after 40k miles of being force fed and having another spring installed- stock spring plus an afc spring. I bought one from the local parts house since I was in a pinch to keep my daily running but it flows 1/2 of what the last pump could. I ordered one from the cummins dealer in state and it's the same pump I bought from Carquest. First thing I did was pop the end off of both of them and look at the spring inside. They both have a tapered spring and one valve instead of 2. I expected that from the local parts store unit. Any how even with the pusher turned on it can't even begin to feed my 5x.016s and 64mm.

Just though I'd share since you can't buy a decent unit from cummins anymore. I'm heading over to autozone to see if their "precision" brand lift pump has the tapered spring. The easy way to tell is if there is a brass screen across the inlet.

Does anybody know where to buy a decent one ? I'd like a fass setup but it's not in the budget right now.

[SCHMITTY]

Here are some parts pics

[SCHMITTY]

Another

[SCHMITTY]

New pump

[SCHMITTY]

Old AC lift pump

[SCHMITTY]

Springs I had in it. It also had 2 valves in it. One on either side of the spring. I couldnt find them in the trash I was going to take a couple of
Pics.

[Bodacious]

Originally Posted by SCHMITTY

I've been using a stock style lift pump with a 140 gph eBay special feeding it. It finally died after 40k miles of being force fed and having another spring installed- stock spring plus an afc spring. I bought one from the local parts house since I was in a pinch to keep my daily running but it flows 1/2 of what the last pump could. I ordered one from the cummins dealer in state and it's the same pump I bought from Carquest. First thing I did was pop the end off of both of them and look at the spring inside. They both have a tapered spring and one valve instead of 2. I expected that from the local parts store unit. Any how even with the pusher turned on it can't even begin to feed my 5x.016s and 64mm.

Just though I'd share since you can't buy a decent unit from cummins anymore. I'm heading over to autozone to see if their "precision" brand lift pump has the tapered spring. The easy way to tell is if there is a brass screen across the inlet.

Does anybody know where to buy a decent one ? I'd like a fass setup but it's not in the budget right now.

Thanks for posting. Very interesting... 5x16's and all. I wonder if any threads exist on this already??

[turbo2387]

Mike, Tyler has another OE one off his 96 we can send up to you if you want.

[Drothgeb]

Here's just about everything you want to know about upgrading the Cummins lift pump.

d89's Super Fantastic Fuel System Escapade - Dodge Cummins Diesel Forum

[SCHMITTY]

Originally Posted by turbo2332

Mike, Tyler has another OE one off his 96 we can send up to you if you want.

Yes I do

[SCHMITTY]

Originally Posted by Drothgeb

Here's just about everything you want to know about upgrading the Cummins lift pump.

d89's Super Fantastic Fuel System Escapade - Dodge Cummins Diesel Forum

Thanks I will read it. I have researched a bit but the fact that the lift pumps from
Cummins and the local parts house are now identical is disappointing. I would like to have a fass setup or the like but the fuel setup I have been using works good enough. Hoping the next $$$ spent is on studs. I'm going to see how long the hg will last wth the Allen bolts , timing in the 20s and a little n20

[SCHMITTY]

Originally Posted by Bodacious

Thanks for posting. Very interesting... 5x16's and all. I wonder if any threads exist on this already??

For the most part it's always been advised to use a cummins brand lift pump if your going to stick with a mechanical lift pump. There are some other threads that mention using a comp cams pn 975-1 inner valve spring inside the lift pump to help it at higher rpms. I don't think that will work with these new style pumps with the tapered spring- which is also very weak.

[95cummins5.9]

Originally Posted by Drothgeb

Here's just about everything you want to know about upgrading the Cummins lift pump.

d89's Super Fantastic Fuel System Escapade - Dodge Cummins Diesel Forum

Thank you.

[jasonc]

What about the upgraded mechanical pump PDD was selling. I think I remember them saying it kept up to about 700hp?

[CorneliusRox]

Originally Posted by jasonc

What about the upgraded mechanical pump PDD was selling. I think I remember them saying it kept up to about 750hp?

x2 that's what I was going to say.

High Performance Modified Cummins Lift Pump - Power Driven Diesel

I never thought about this, but I did a new one about six years ago and it looks like the new style, not the old. Then I started loosing pressure at ~3000rpm.
I will definitely be trying out a PDD one next time I need one, I just don't drive the truck much now days unless I'm towing. :-(

[SCHMITTY]

Turbo2332's buddy is selling me his old one. I called both places and they are letting me return them.

Stopped at autozone and it's the exact same pump cummins sent me - same "cummins" stamp and same made in China stamp.

I'll give the pdd pump a try next. We have an annual drag race /dyno day up here and it's in a month. things keep popping up and stealing my race truck money lol. Head studs , better fuel setup will hopefully happen this year but not within a month.

[SCHMITTY]

Originally Posted by Drothgeb

Here's just about everything you want to know about upgrading the Cummins lift pump.

d89's Super Fantastic Fuel System Escapade - Dodge Cummins Diesel Forum

That is a good link thanks

[Bodacious]

Such good info here. Thanks for posting.

[SCHMITTY]

A lot of what I typed is my opinion. I haven't done any tests or anything other than crack it open and look inside, drive for a couple days and make an assumption. The spring did compress a lot easier also.

[kawi600]

If I had a truck making over 500hp Id be looking at a front cover mount pump like a waterman or something. Id imagine the pdd pump is simply a pump with a heavier or dual spring setup.
One thing Ive never liked about the stock piston pump is the big pressure spikes, its like a hammer on the inside of the fuel system that could make it easier to dislodge loose filter paper or metal screen bits.