Fuel pressure is at a nice 14 to 17 and only drops to about 10 to 12 on heavy acceleration. Just got back from my mechanics and he looked at all my work and agrees that it seems like something with the pump. Working to schedule a time to pull it again. Aaand hes gonna give me a deal on another pump i can use for a core for ratman to build me one of his pumps.

With over 400k on the engine and some blow by, Im thinking about redoing the bottom end when i get the ratman pump. That way i can make sure kdp is good, skip a tooth and use stock timing mark on the pump, and im thinking about trying do do a conversion to a 24v head. Im just now starting to look into what that involves. Maybe going for a mild ported one. Swithing to non ic pistons, possible coated ones, and gapless rings. Idk I just figure the bottom end work is going to cost enough that i might as well just "gittrdun" if im going to go that far financially.

Still need to figure out the loud droning at 60+ under load. If i go full getrag rebuild ( not doing it myself) with a valair dd organic nv conversion clutch and flywheel, its going to only cost a few k less than just doing the g56 swap with a built AD in a heavy duty cast iron case with adapter plat fly wheel and clutch. The np 205 is gonna need to be gone through either way.

Going with a 24V head will need to be matched with pistons that have room for the 4 valves a cylinder if I am not mistaken.

I would think a ported 12V head from PDD [Power Drive Diesel] would be an easy yet good upgrade for a head.

Wow you really slid down the rabbit hole on this build. You went from what is likely a getting air in your fuel lines issue and the truck starting funny after it sits a bit…To a FULL on ground up build, with a rebuilt motor with some parts that may not want to play well together.

Have you done any research on fitting the HUGE 6 speeds in these early 1st gens? If not you should check out BHD’s Road Tractor build. That way you get an idea of the custom transmission tunnel welding / work he did along with other tweaks to get it to fit. It is a VERY good read.

Before throwing several thousands of $ or more at your motor. Be aware excessive blow by can be caused by something as simple as a vacuum leak.
Have you checked for leaks in your system?
Things like cracked / broken lines, disconnected connections. The vacuum pump sucks air from these leaks and pumps it into the timing case. Which causes what appears to be “blow by”
I have a couple of motors with 400,000 miles and they run great still.

Just trying to help you make an educated decision on if you need to really rebuild your motor.
If you don’t want to hear this sort of stuff, I will be quiet and just read along your thread of randomly throwing cash at “problems”.

Im definitely going to have to look into that. I know that my mechanic left my power steering pump haning when he was working on my pump and broke my oil pressure sensor when he put it back in. Isnt the vaccum pump the aft most part of that assembly?

I was looking at the work Tim at decent garage did with his g56. With the leveling kit i didnt think there wasnt much other than re doing the hole for the shifter and if i remember something about one of the linkages. Its been a year since i watched those videos so maybe i should look at them again. The bottom end rebuild of the engine is a future thing. Figuring out what im gonna do with my trans is another story. Id like to at least get the bearings and 3rd syncro replaced and since the 205 has to come out to do it, id like to get it looked over and at minumim resealed.

The starting funny thing is the same issue that we think is/could likely be air getting into the system. Short of pulling the fuel pump off and completely going over it again, ive done and redone every other connection that was touched between it running good but leaking to not leaking and not wanting to start.

As for the fogging up a parking lot when i do get started, ive got an swrench coming in tomorrow. Im going to out the pump back at the factory mark and see if it changes at all. Maybe the mechanic didnt shim it right i lnternally and the timing is too advanced. That shouldnt cause the apparent loss of prime, but if it helps with the smoke at least its another symptom gone.

I get addicted to wrenching on thi gs when i start to see improvements hehe much like gym results. The grounding fsctor i suppose is the fsct that life is expensive and had to be prioritized.

Those are Chinesium castings. I would like to port the spare head I have in my shop.

I know that, but there are ported and re machined, from what I heard, in the USA by PPD.
I have also watched videos that show the power improvements they make in before and after DYNO tests.

Hard to find stuff that is 100% built and made in the USA anymore.

Any mention of the different adapter plate and starter need?
How about moving the transmission crossmember back on the frame and drilling new holes in the frame?
The fact that the input diameter is bigger so a clutch swap is needed?
You mentioned linkage. You must be referring to the 4x4 linkage, but do not forget you will also need to make a strong custom bracket to mount the 4x4 lever and linkage to on the new transmission.
Obviously both driveshafts will need to be done.
I have seen most people need to raise their cab [ AKA body lift] for the bigger G56, or cut out and make a bigger tunnel for the transmission. A leveling kit does not add room between the frame mounted crossmember and the cab...

I know the youtoober's skip some steps in most videos, but to be honest most people do not want to watch all the time consuming steps.

Lots of stuff to think about when modifying things.

Have you tried the tip I mentioned weeks ago to you about running the truck of a NEW temporary fuel system...yet?
A jerry can of diesel in the bed [or cab] with some fresh fuel lines to and from the motor will suffice. That way you can eliminate all most all the OEM fuel system as a culprit of your issue.

I would be doing this LONG before having discussions of getting a rebuilt pump installed. How sad would you be to find out it IS a bad fuel line, connection or even an 30+ year old O-ring in the fuel line connection clips at the fuel tank or at the LP?… AFTER spending the big $$,, just to find out it was a 99 cent O-ring.

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very true. I must have completely missed missed suggestion entirely. Ive got cans i could use. How would that work, plumb rubber fuel line from External tank to the lp, re prime and see how it goes? When i get out of work ill have to dig back through the thread and find it. **I JUST had a conversation with Evan from ratman. As soon as I told him what was going on he sent me a video explaining what the believes the problem is, and I hope he is right. If so, its just a single banjo bolt.**

Yes full jerry can of diesel, NEW lines to and from engine.
The line to the motor would hook right to the LP. A trick I have used for years in to thread a lug nut AROUND THE OUTSIDE of the fuel line so it sinks to the bottom of the jerry can.
Prime system and drive the truck. Park the truck and see if it starts hard like it has air in the system.

IF NOT then you know the problem lies in the old fuel system.

I told you about the new fuel lines run into a full jug of diesel in the return PM I sent you on the 2ND of NOV.
I told you that it would help pin point the issue of air in the lines.

Then I said we should be having this discussion on the 1st gen page so other people might be able to pick up pointers in case they have an air in fuel issue.

Since I have people asking me about this problem several times a month I know it can be a common issue.