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Old 02-13-2020, 12:31 AM   #4 (permalink)
Self Ignition
Join Date: Jan 2018
Location: California
Posts: 99

Oh boy, so I have some questions and some pictures. I hope my questions do not come off as dumb but here goes. I am pushing my sick motor to the bitter end here while I sort out a new one. I have installed a coolant pressure gauge that I can watch as I drive and have been able to baby her pretty good with that. The truck has been venting after relatively short drives and things were getting worse and she started hydrolocking again until I learned to vent ALL the pressure after parking to prevent the pressurized coolant from being pushed back into the bad cylinder. Fun times!!!

So, knowing I will have to time a new IP as my old one is suffering from the 36 code (pulse width too long) I went ahead and got GMTD scantech ready to go. I noticed I can shut off cylinders. Now I am thinking.... other than losing 1/8 of my power, what if I shut off the offending cylinder(#2). something tells me that I would have to drop 4 to keep it rotating right.... probably 2,3,5,8.... I think I can make it without this but it was just a thought and thought I would ask.

Ok, next is the IP on the donor. I can see from the badge it is a DTech DT650003R (per website it is for 1994-2003 GM 6.5L Turbocharged Diesel*) and the * says 1994 owners must match OE number.

Being that i happen to have the 94 c3500 at a best glance I can see that it appears I have a standyne 5521.

From what I gather that would mean that I CAN run the ip on the donor motor, correct? I am sorry about the pics, I was trying my best with a scope, I can get better pics if proper ID is still not doable with these.

That said, it is a lot of work parting out a truck! Being that I am strapped for cash I thought this would be the best way to try and get a decent motor and be able to recoup my investment in the truck. The truck had pretty worn suspension and the tranny was just starting to signs of needing an overhaul. I should post some of the parts in the marketplace...

I pulled all the accessories on the stand and removed the glowplugs and did another compression test finding some cylinders would sometimes show better numbers (340+) than others but some would not so at this point I will go two ways with it... as OKDually advised (after a leakdown test) inspect the main webbing etc and if it is showing signs of old age I will be forced to clean it up and throw it in but if it still looks good I guess I ought to do all the bearings and rings and use my studs and heads from my old motor (only 10k on heads).

One final question, I redid all the plastic retainer buttons on my old trucks heads when I replaced them 10k ago but what are upgraded rocker assemblies and really I don't think the wallet will allow them unless they are worth a kidney somehow.
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1994 GMC C3500 6.5L TD crewcab dually utility bed 311,XXX smiles 4" Diamond Eye exhaust, Hushpower muffler, Glowshift gauges, Lubrication Specialist ss oil cooler lines
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