Glow plugs are working. Didn't physically pull them out to see the glow but did clean each connector and they all register 0.9-1.1 ohm when testing. I've tested voltage from the relay to each and during cycle, all good there. Glow plug light on dash burns for about 6-8 seconds on first key turn, about 2 seconds if you switch it off and back on for another cycle.

Let me elaborate a little on the PMD's, want to make sure I'm telling you guys right. PMD# 1 is the grey Stanadyne, was screwed to a simple metal plate on the intake beside IP, and is dead. It looks pretty old and is the one I got with the truck. After going through the no-start test progression, that's when I got the $25 used one. Screwed to the plate, plugged in and she ran beautifully for about 30 mins then died. No gap in that one on the existing flat plate, just chalked up the quick failure to it being a $25 PMD. That's when I ordered this new PMD kit (brand new PMD, came in a Flight Systems box) with the heatsink that didn't fit together. Plugged it in as-is with flat plate replaced by heatsink (the one in the pic with gap present) but it never ran, would not hit or even sputter at all, so that one has zero hours on it. Not sure if it's a dud or what.

Just making sure I was giving you guys as many details as I can, and thank you!

 

the metal plate on the intake is what killed the used PMD likely-that and age.

the metal plate can't remove the heat that the PMD generates when in operation-aluminum heatsink only and it must be large enough.

As for the new PMD-could be that there is a problem with th extension housing?
When you get the PMD sit flat on a heatsink with hat transfer paste/pad between them,try connecting that PMD to the original IP harness without the extension and see what happens.

Could be bad out of the box?
Or a bad extension harness-I would think twice about dealing with that vendor again.

 

I agree, that metal plate was doing nothing to get rid of heat. When the truck died the PMD was far too hot to even touch!

On that extension cable, I pinned it out and have continuity all the way through, connector to connector. Could be an issue at or with the connectors mating I guess? Great thought, I will be very diligent when checking this and will follow your advice.

I called the Pensacola Diesel guys this morning about this situation, said they have never had a Flight Systems PMD dead on arrival so that scares me a bit. They were awesome though and are overnighting me a new heatsink, used PMD and new PMD, and a box to send the other stuff back. Pretty dang good service, just hope the parts work out!

 

I got my replacement PMD's and heatsink, a replacement used one and a replacement new one. Used was DOA. The new one got it going, which proves our though that the issue is pmd related.

Now, it started on the third 10 second cycle start attempt, was a really stumbly start and bellowed white smoke. The smoke quickly cleared up and she was running good. Ran for about 40 mins and shut off just like it had been, like someone turned the key off. After there attempts it restarted, lots of white smoke which cleared up, ran about 5 mins and shut off the same way. Again third attempt started, ran about 2 mins and shut off. After an overnight sit, started on second try, ran about 2 mins and shut off. Same thing once more in the afternoon and that's where I am.

I only replaced the pmd, have it in the heatsink properly torqued with the heat transfer pad. #9 resistor installed, it's on an extension harness on the inner fender well. Ground is on the ip and also from the heatsink to the fender well.

I did not replace the ops or cps, wanted to hold off and truly diagnose the problem first. This is the third functional pmd this thing has killed in short order, what can possibly be causing this? I have checked and rechecked the lift pump and it works on start up and shortly after. One thing I did notice is during the first 40 minute running session, I opened the t-handle and got not fuel coming out while running. Truck did not stall when I opened it.

I'm really lost as to what the problem is. Feel like it's some kind of electrical issue but I really don't know. Anyone have any ideas or suggestions? I'm up for trying anything at this point!

Thank you in advance!

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Also, if it matters it is a 6' extension cable running to the pmd.

 

Ok there are several things going on here.

A PMD alone does not cause the extended cranking you are going through-you have a serious air leak in the fuel and/or a CPS/OS problem.

The white smoke makes me think air leak is more likely.

Replace the IP return line with clear diesel rated tubing and whatch that line for bubbles to confirm when engine idles safely.

clean/replace your fuel lines to/from the filter housing so uou know there is unobstructed flow.

A blocked IP return line will cause an overpressure situation in the IP that will cause it to shut down.

A bad IP fuel solenoid can draw too many amps and kill PMD's also-A rebuilt IP might be required to repair this?

 

Thanks for the feedback racer, man I really appreciate it.

I'll start checking those fuel lines and do the clear tubing test first. I believe I'm into dropping the tank to fully check those lines right, good times!!

Sure hope I don't have to replace that IP, was really hoping that wouldn't be the problem.

Thanks again and I'll keep it posted!

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Also you wouldn't happen to know off hand what size those fuel lines are would you? Can save a trip back out to the store if you know what they are. Thanks again!

 

Ok the lines from the tank are metric but fittings can be bought to transition from metric to 3/8" and 5/16" neoprene or what ever rubber is diesel rated.

papco part number 905-352 =3/8*4 inches 16mm nut
papco part number 905-350 =5/16*4 inches 14mm nut.

The lines from filter to IP I think is 5/16" and to Tee valve is 1/4" but if you were to cut some samples to take with you would make life easier.

Another thing to check into is the fuel filler cap,if the vent in the cap is plugged vacuum in the tank can overcome the LP's ability to move fuel-if you get a strong noise when you open the filler cap it likely needs changed.

A large D on the cap and/or it being green is what you want-don't let the parts guy sell you a gasser cap since that is often where the problem stems from,they are vented differently and won't work.