Will 12-valve pump fit 24-valve engine?

Elliot Naess · 02-24-2018, 08:08 PM

I am still not sure whether Millicent's engine has survived the 2017 ordeals, so I am trying to think ahead, in case a new engine is needed.

Millicent has a 5.9 12-valve -- that is, it has mechanical fuel injection. Cummins switched to electronic injection with the 24-valve version.
What if I come across a good deal on a 24-valve 5.9, or even a 6.7? Can my mechanical injection pump be bolted to the newer engine?

Robin97396 · 02-24-2018, 08:29 PM

I'm curious why you wouldn't stuff an 8.3 in there since it's a transplant.

I'm thinking the mechanical pump won't mix with the electronics of the 24 valve engine.

Gdog 5651 · 02-24-2018, 08:54 PM

I believe Robin is correct the very early 24 valve engine used a totally different pump and very few years later went to common rail fuel system which would require a different cyl head I am not sure that the heads would be interchangeable either way I think the electronic parts would be incompatible either forward or reverse engineered I am not sure but I think the pump would not mount without a new rear cover more trouble than it could possibly be worth.

Kubla · 02-24-2018, 09:01 PM

common rail in 2003

Booyah45828 · 02-26-2018, 09:31 AM

24v 5.9 that uses a vp44 will work. Everything newer I believe is rear gear train and it will take a lot more work. As far whats needed, you'll have to remove the PCM, injection pump, and the timing gear case. You'll then have to swap over those items from your 12v engine, fab up some injector lines, and you should be good to go. There are better, more in depth resources available online if you actually do take the step. I imagine some of them are pretty in depth step by step wise.

Elliot Naess · 02-26-2018, 12:01 PM

I would love to install an 8.3, but they are less common and likely to cost more.
A stick shift would also be a good upgrade.
I dream of a "get it out of here" bargain on a wrecked delivery truck with 8.3 and ten-speed.

As for mixing the P (inline) pump from the old engine with electronics on a new one.... The idea is to get rid of all the electronics.

I sure appreciate the input. Please keep it coming.

Oh... one more question, which I should have included to begin with: Are there any significant differences between the commercial engines and the Dodge pickup-truck engines? In the basic engine, I mean. The "long block" assembly.

Robin97396 · 02-26-2018, 01:17 PM

I've seen a manual installed in a FE before. It was neatly done but the shifter came through the floor a ways into the bowling alley and presented quite a tripping hazard. It also had a interestingly long crooked shift shaft reaching forward to over the doghouse. About 15 seconds of looking at the shifter cured me from ever wanting to go that route. However it is doable apparently.

It would be cheaper to buy a rust belt bus with an 8.3, and maybe a good transmission, than buying just the 8.3 engine. This is something I always wanted to try. A mechanical 8.3 would be sweet. It would kick hiney in my 26'er.

Mr4btTahoe · 02-26-2018, 03:51 PM

Yes you can P-Pump a 24 valve. Its actually pretty common in the pulling world.

Here is a kit... I'm sure there are others out there. Just need the timing case, pump, injector lines, pump gear, etc. If you've got a core p-pump engine, it would be cheap/easy.

https://puredieselpower.com/dodge-pr...rsion-kit.html

Common rail is a different beast entirely. So.. a 12v or 24v long block would be the route to take.. then re-use your pump, injectors, lines, timing case, etc.

Is it still puking oil into the cooling system after the oil cooler replacement?

Elliot Naess · 03-13-2018, 10:31 PM

Thanks for the info, guys! And specially the link to the kit.
The kit is rather expensive, but yes, I would indeed have the 12-valve parts donor.

Again... this conversion would be of interest only if the existing engine proves fatally damaged.
So... the timing case and the gear and such from the 12-valve would bolt onto the 24-valve? Those kit parts are not "adapters" with one bolt-pattern on one side and the other bolt-pattern on the other side? Then any thru-2002 5.9 would be a fairly direct replacement for a 12-valve long-block. Sweet.

And... I have not installed the new oil cooler yet. But it has arrived.

Booyah45828 · 03-14-2018, 09:30 AM

I don't think you need that kit if you have a donor 12v. That kit is only if you have a 24v and it has you source your own injection pump. The only real fab part required is the injection lines.

Elliot Naess · 03-14-2018, 01:32 PM

Thanks for confirming that!

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