Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×

Thread Tools Display Modes
Old 04-01-2023, 11:15 AM   #1
New Member
Join Date: Feb 2023
Location: Denver
Posts: 4
24V 5.9L VP44 to Ppump?

So I think I may have found the perfect bus. Well almost perfect, as you can see from the title it has a 2000 24v 5.9 Cummins power plant.

From my research the biggest issue with these engines is the following scenario. The fuel lift pump starts to lose pressure in the output to the VP44 which then, due to a lack of flow, causes the VP44 to get hot, which in turn melts an electronic chip on top that causes problems without an ID code.

My questions:
Has anyone swapped out the lift pump for a more reliable one than stock? have you had any issues? does this completely negate all the VP44 issues?

If you really want some serious power I have read about the P-pump being installed on the 24v, takes a good amount of work but ends up being a super powerful engine and there's ample videos online about it. My question is does this fix the lift pump problem? does it just make the poor pressure from a bad lift pump less critical? or do most of these VP44 to Ppump swaps include an upgraded lift pump?

If a VP44 to Ppump is theoretically possible would it be doable in the working space of a flat nose skoolie? Any known required modifications for fit?

My hope is that I can get good reliable use out of this engine with a KDP cover and installing a more reliable lift pump? Is that naive?

As always thanks for your input.


zz_shoots is offline   Reply With Quote
Old 04-01-2023, 02:19 PM   #2
Join Date: Mar 2022
Posts: 148
Engine: 12V 5.9
Upgrade the lift pump.
La Camioneta is offline   Reply With Quote
Old 04-01-2023, 08:43 PM   #3
Bus Nut
fo4imtippin's Avatar
Join Date: Oct 2021
Location: Jax Beach, FL
Posts: 524
Year: 2003
Coachwork: BlueBird
Chassis: TC2000 28ft
Engine: Cummins ISB 5.9 24v, MD3060
Rated Cap: 14
24v gets a few better mpg. Also less likely to have a 545 trans than a 12v. Also has cruise control. Just upgrade the lift pump, get a fuel pressure gauge. Then you can actually flash a high hp program on the ECU if you want.

Vp44 is fine if you keep it fed with fuel.
fo4imtippin is offline   Reply With Quote
Old 05-23-2023, 08:00 PM   #4
Join Date: Aug 2020
Location: Alabama
Posts: 192
Year: 1996
Coachwork: BlueBird
Chassis: International 3800
Engine: DT 466 Mech. Spicer 5 speed
Rated Cap: 34
More than likely the pump has already been replaced at some point. The original pumps used lead free solder, which contributed to their failures, and I would think the replacements were repaired with leaded solder. Even if a VP44 fails, it's not the end of the world expense wise to replace it. I have a VP44 in a pickup, and installed either an air dog or a FASS pump-- I don't remember. There are even upgrades to the stock pump that are supposed to be much better than the originals-- just do some googling.

The P-Pump or VP44 are reliable fuel systems, and at least if there is a failure-- it does not take out the entire fuel system like common rail systems often do.

Don't worry-- be Happy!
PorchDog is offline   Reply With Quote
Old 05-23-2023, 09:30 PM   #5
Bus Crazy
Join Date: May 2018
Location: topeka kansas
Posts: 1,587
Year: 1954
Coachwork: wayne
Chassis: old f500- new 2005 f-450
Engine: cummins 12 valve
Rated Cap: 20? five rows of 4?
Lift pump

When you install the lift pump. Put the pump by the fuel tank and push the fuel to the engine. Also install fuel pressure gauge near the engine so that you can keep an eye for the pressure feeding the engine. By keeping the engine controlled by electronics, the 2000 and 3000 series transmissions are a little easier to swap into your bus.

magnakansas is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 09:06 PM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2023, vBulletin Solutions, Inc.