Archived 99 New lift pump PSI 7-12 is it bad?

[jmos4]

Hi,



I had my lift pump go bad last night was normally about 14-12 and under hard throttle it would go to 9psi last night it went to 7psi at idle so I changed it with a new Napa Replacement external carter style pump, it is relocated on the frame rail



The new one after bleeding several times at the Banjo bolt on the injector pump would only get to 9-10 at idle and go as low as 7 under hard throttle

I did this at the Carowins Park on the NC/SC, I drove it back slowly below 1400rpms to our hotel in Concord NC and this morning I attempted to bleed again according to the manual and it starts and runs yet still PSI is only at a high of 12 and goes erratically back and forth from 7-12



Do I need to drive it some for it to self-bleed or is the pump bad?

Do I need to bleed the injectors?



Any help or advice would be great as I have to drive back to MI with a trailer this weekend and would like to not damage the injector pump or get myself stranded



thanks

Jim

 

[jmos4]

update:



just took for a test drive, after reading a few post, I took the fuel cap off and ran for a bit and then put back on tight



now I have more a steady PSI of about 9-12 running although now under load it goes all the way to below zero and back up erratically under no load it will rev to 3000 with a constant 9psi



the truck does have larger injectors and blows black normally under hard throttle now it still does this though much more than usual



is my injector pump bad something else should I replace this pump bleed again or something else



if anyone has a idea as I am really starting to panic a bit, as I have to be back in MI next week and do not know what should be the course of action



anyone know of a honest repair facility in Concord NC that I could take it to?



thanks

Jim

 

[JLandry]

Before you get too far with this, it'd be wise to verify the fuel pressure with a test gauge. You may find out the pressure is higher than you think it is.

Best regards,

John L.

 

[Bob4x4]

Both Cummins and Dodge dropped the psi specs years ago. Do flow test,if it passes drive it home

 

[Joe Mc]

Since you relocated the new pump to the frame rail, is the sender unit close to the relocated pump? When you installed the sender unit did you have a piece of hose from the "T" to the sender? If so there could be air in the hose. If this is the case (sender still in eng compartment and hose from "T" to sender) I'd move the sender and "T" just down stream of the relocated pump - like "as close to the LP as possible and without a length of hose. If you have air in the hose to the sender this will give fluctuating psi readings. As suggested above flow test it. When you get it home you'll have time to tweak things.

 

[jmos4]

Hi all,



Got home ended up the sending unit/harness or gage has a bad connection I ended up installing a manual gage and was 10-15 with my old pump going to redo the entire system this summer as that was a scarey thing to have happen 800+ miles from home and hauling a trailer



I took back the new pump thinking it was bad and all they had was an Airtex that was a in-line design is this a good replacement or should I find another carter style?



thanks again

Regards,

 

[JLandry]

The Airtex gearotor pump is a good unit. Be sure and use a pre-filter ahead of it to protect it though.



3/8" inlet/outlet pre-filter part numbers are: NAPA 3250 or Baldwin BF1173



Regards,



John L.