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Coolant leak is back, Plus oil sludge! 88GMCtruck's 1999 K2500 L65 = more problems.

Well... It's together.
















And it didn't blow up. :D

After getting 99% of it together and priming the injectors, it was time for the engine flush. Without the turbo attached and the turbo oil feed in the oil filler, we flushed the oil system. Used 7 quarts of off-highway #2, 1 quart of ATF and a new filter. Let it idle for about 2 mins or so, then drained it out. Filled it with 8 quarts of 15w40 Castrol Tection Extra Diesel Oil (typically I run Shell Rotella T but this was on sale and it's only going to be in there a short time compared). Bolted on the turbo after a bit of fighting with the return tube...

Fired her up. Sounds perfect at idle. It's all clattery clanky like it should be. After letting it idle, checking for leaks, etc, it's time to give her a test spin.... Pull out onto the road, give it throttle and boost builds... *whirrrrrrrrrrrrrr* (and not in a good way)..... Crap.

The turbo is munched. We had some issues with the shaft and are pretty sure it's bent a little bit. IMO it doesn't spin straight so it's probably a ticking time bomb. Over 1,000 RPMs it makes a hell of a spooling sound, kinda like a shop vac. Brought it back home, let it idle up to operating temperature to bleed the cooling system, etc. Everything, except the turbo checks out. My oil cleaning job did a very good job, even after the truck ran for probably an hour, the oil is still honey colored and clean. I'll be keeping a close eye on it and seeing how it changes over time.

So, I'm looking for a new (used) turbo now too. Anyone have an affordable lead on a GM-8?
 
Everything about that screams "bachelor".....Sigh, such fond memories.....

:)
that's where I rebuilt mine and I'm married. She's def a keeper.
Ehm. You should see the things my father does. I can't even begin to count the time my mother has found motor parts in the freezer, oven or dishwasher. Or gun parts baked in the oven to cure the teflon moly finish. I'm going to be one of those guys. I love rebuilding misc things in my livingroom. Remember, I washed all those interior pieces of my truck in the dishwasher too :D
 
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Remind me to invite you two and Orion Thade over for a weekend when and if I have to rebuild/replace my motor.:thumbsup: You all do great work and I cook pretty good steaks.:agreed:

Any time. I recall seeing some ARP studs sitting on your shelf that need to be used.
 
Remind me to invite you two and Orion Thade over for a weekend when and if I have to rebuild/replace my motor.:thumbsup: You all do great work and I cook pretty good steaks.:agreed:
Paul, I totally missed your post in the sea of text up there. If I have the time and anyone ever needs a hand, I love working on projects with other people. Plus it helps to have already done it once!

Honestly once I start working and get the time/space I would like to start building a new heart for this thing.
 
Remind me to invite you two and Orion Thade over for a weekend when and if I have to rebuild/replace my motor.:thumbsup: You all do great work and I cook pretty good steaks.:agreed:


Paul, I totally missed your post in the sea of text up there. If I have the time and anyone ever needs a hand, I love working on projects with other people. Plus it helps to have already done it once!

Honestly once I start working and get the time/space I would like to start building a new heart for this thing.

x2 It was an awesome learning experience, just really poor timing for David. I've always loved working on projects, be they on the farm, in the shop, or in the driveway. I haven'd banged up my knuckles this good in a while, I really had a lot of fun. Though, torquing the heads down in 3 stages is a PITA...at least I borrowed my dad's looong Proto (250 lb-ft capacity) torque wrench. They went on a whole lot easier than they came off, studs for the win over TTY bolts.
 
Devin is right, aside from the timing, I began having fun once the thing started to go back together. It also helped that I had 3 other people here helping me (Devin and 2 others) because they all wanted to lend a hand and get it back on the road. I will admit, there was a period there that I just about gave up on it due to frustration/anger, but overcame it.

Right now I'm looking to find a suitable replacement turbo. I think I may be calling up and getting an ATT under the hood. It's still not the time but there seems to be a shortage of affordable GM turbos and reman ones cost more than an ATT does to begin with. A little peeved that the turbo was munched, just glad it never spontaneously combusted into the motor (well, entirely that is).
 
x2 It was an awesome learning experience, just really poor timing for David. I've always loved working on projects, be they on the farm, in the shop, or in the driveway. I haven'd banged up my knuckles this good in a while, I really had a lot of fun. Though, torquing the heads down in 3 stages is a PITA...at least I borrowed my dad's looong Proto (250 lb-ft capacity) torque wrench. They went on a whole lot easier than they came off, studs for the win over TTY bolts.

remember your supposed to retorque after awhile which is one of the reasons manf went to TTY
 
I was looking at that turbo. I'm leery buying a used one on ebay, nor do I want to wait 4 days for the auction to end and another 4 days to ship it from NY.
 
remember your supposed to retorque after awhile which is one of the reasons manf went to TTY

ARP directions didn't say anything about that. We went in 3 stages to 130 Ft LBS per ARP directions using 30wt oil. The bolts we checked later with the torque wrench were still at 130 FT LBS.
 
You do not need to retorque if you are using Felpro Head gaskets. They do not need retorquing. The crap printoseal ones did. I don't think they even make them anymore. If you used the blue Felpro's your good to go.
 
retorqueing is a good general practice, like you might do on the wheels too. Its recommended by Cometic gasket as well. Although since its a PITA I think I would settle for checking it a few days later before putting it all back together. It doesnt catch any changes due to heat cycles though.

If you just want a used GM8 I have one you can have for $200 plus shipping. I have never personally used it, recently acquired from another member, and only planned to compare it to the GM4 and ATT. I could ship it out Monday, probably like $35. Although if you have intentions of towing with that truck I would highly recommend the ATT for its quality and simple install. If you had the time to mess with things and wanted cheap and new then I would ebay an HX40WII, which would take some fabrication/welding on the down elbow.
 
I wouldn't spend 800$ on an ATT on a motor that you are unsure of the condition. That can easily be added later. I have what I think is a GM3 or 4. It was supposedly rebuilt but the wastegate is jammed. I'd sell it real cheap. Maybe be a simple fix. Don't know, I don't screw with Turbos, just replace them.
 
You do not need to retorque if you are using Felpro Head gaskets. They do not need retorquing. The crap printoseal ones did. I don't think they even make them anymore. If you used the blue Felpro's your good to go.
Yup, used fel-pro everything for gaskets on this truck.

retorqueing is a good general practice, like you might do on the wheels too. Its recommended by Cometic gasket as well. Although since its a PITA I think I would settle for checking it a few days later before putting it all back together. It doesnt catch any changes due to heat cycles though.

If you just want a used GM8 I have one you can have for $200 plus shipping. I have never personally used it, recently acquired from another member, and only planned to compare it to the GM4 and ATT. I could ship it out Monday, probably like $35. Although if you have intentions of towing with that truck I would highly recommend the ATT for its quality and simple install. If you had the time to mess with things and wanted cheap and new then I would ebay an HX40WII, which would take some fabrication/welding on the down elbow.
I was thinking of ATT since if i'm spending some money why not upgrade and this truck is primarily a towing pig, but a used gm8 would suffice as well. I'll get back to you today on my decision.

Make sure you use a good thread sealant on the studs on the water jacket side.
Used teflon tape. I can't remember where I read it but it was recommended and it's something I had and know how to use.

I wouldn't waste 800$ on an ATT on a motor that you are unsure of the condition. That can easily be added later. I have what I think is a GM3 or 4. It was supposedly rebuilt but the wastegate is jammed. I'd sell it real cheap. Maybe be a simple fix. Don't know, I don't screw with Turbos, just replace them.
I'll pass on the jammed wastegate, I'm not sure what is different between mine and it but I don't need another project on it. As far as the ATT, i'm pretty sure the motor is fine now, although who knows. Can't really tell otherwise till I can put a few miles on her, but so far so good. It purrs like a kitten at idle...





Ok, a very angry clackity clanky kitten :D
 
Good luck and good job David, Seems that tear down and rebuild was lighting fast.........Still pullin for ya,.... you and Devin......and all the helping hands make it look and seem so easy!

I hope she's as good as NEW!
 
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