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GM 3500: After changing head gasket, injecor pump and injectors

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After changing head gasket, injecor pump and injectors on 93 gmc turbo diesel 3500 6.5 the truck started to work like a brand new truck I added some motor flush and started the truck left it on for 10 minutes after 10 minut or so it started to on full throttle making a lot of Blake smoke with some knoking sound on the pass side of the engine where the turbo is and the truck wouldn't turn off disconnected battery's alternator steel wouldent go off pinched the fuel line after 1-3 min it turned off. It made so much smoke that couldn't see nagbors houses, even the fire department showed up from 10 blocks away they said they sa the smoke. And now I checked the oil level it is about 2" passed the normal limit
Hi, it sounds like you had what is called a runaway diesel. The engine was probably running on the oil in the crank case. Drain the oil and get it back to the correct level first then try to restart it.
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There are videos on youtube if you search runaway diesel also if you want to search that and see what it looks like when it happens.
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Customer: replied 4 years ago.
I did do that last night, I changed the oil also opened the inteche there was water and oil in the air inteche so I took it to a test drive it is making knoking noise it gets louder when I push on the throttle sounds like valve, pushrod or something that's in the in the motion of the engine hiting something. Before I changed the head gasket I got this nois on cold start but went away after few second seems like the oil lubed it and went away also I changed all the springs becouse one was broken.

Also after the test drive I opened the oil fill cap there was water on the cap

After Ithe head casket change it worked like a brand new truck very responsive and quiet. I head a loud noise like something broke following with the runaway
Any India's ?

I am going to open the heads again but could this be pistons?
It could have caused major damage from the run away. A knock is usually a rod bearing but the runaway could have damaged other internal parts also. If you have a slight knock, I'd start with checking the rod bearings.
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Customer: replied 4 years ago.
I will open the heads see if anything if broaken in ther or bent if I don't see anything on the head or pushrods how do I get to the rod berings?

Drop the oil pan and remove the connecting rod caps. Make sure you pay attention to how they come off. They have to go back on the same way they come off. You can't install the caps backwards or you will cause more damage.
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Customer: replied 4 years ago.
Ok I will check that first as it sounds easer than head work.

What do I look for and when puting it back is there a torque I have to use to tighten the bolts .

I have never done motor work I just have photo memory and good with my hands ( handy guy) with little reading YouTube and just answers I can do anything :-)! Just point me to the right direction when the problem is solved by your help I will PayPal u 150$ tip
Ok, good luck. The connecting rod nuts get torqued to 48 ft/lbs.
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Customer: replied 4 years ago.
Will the rod berings affect the way the truck starts? Is there anything else I can look for other then the berings before I open the heads as I have td it'd a big project to open the heads

Customer: replied 4 years ago.
Also when I was changing the head gasket on the package On the gasket it said to put a thin layer of rtv and after I installed it I came across a forum some said do not put rtv on the gasket could this have been one of the problems?
I never heard of putting rtv on a head gasket, only a spray on sealer.
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No, the rod bearings will not contribute to a hard starting issue, only cause a knock if there is too much clearance between the bearings and crank journal. Without me being at the vehicle its hard to say but try to listen where the noise is coming from in the engine and that may point you in a direction.
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Customer: replied 4 years ago.
Sounds like its coming from the heads on both sides
Also could I have bad oil pump how can I check to see if the oil pump is pumping in of oil? Or that won't be an issue?
Where can I get the spray on thing you are taking about for the gasket what is it called ?
Customer: replied 4 years ago.
What are the symptoms of black, blue or whit smoke ?
Customer: replied 4 years ago.
I took the driver side head took the glow plugs and the injectors out and have 2 of the glow plugs half broaken/melted , have like welded look to the injectors from the broaken glow plugs and there is a small crack on all 4 ports where the diesel gose to the cylindr, paid $450 for the glow plugs and the injectors together from eBay could the cause of this be from glow plugs? So I can return for refund. The injectors are marine injectors please let me know ASAP if you want pictures give me email
All that damage probably happened from the runaway. What ports are cracked, the injector ports in the cylinder head?
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Customer: replied 4 years ago.
Yes the round chrome port has a oval shape hole and T on it
Also there is no other half of the glow lugs melted I guess?
Customer: replied 4 years ago.
Looks like this port are changeable. Do you know if they are ?
No, I don't know if you can replace the port only. Maybe check with a GM dealer on that.
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Customer: replied 4 years ago.
Do you think the injectors are fried ?
I have no way to tell that without being there, do the tips look ok or do they look damaged?
Customer: replied 4 years ago.
Tips are ok. I am thinking since the truck worked on super high rpm assuming 20000 rpm the heat could have damaged the springs.
Is there a way I can measure the spring tension? What is needed to test injectors?
Or how much will a shop charge to test the? Or what is a normal price

I am going to take the driver side head now and il remove the oil pan next and will keep you posted.

by any chance are you in Los Angeles area or do you know any good shop in Los Angeles area to take the head for leak test and the injectors

Thank you very much!!!!!
The first test to check the engine mechanically would be doing a compression test. I doubt it reached 20,000rpm, it would not have stayed together at all but I'm sure it was excessive for a long time. You will need a diesel compression gauge to do that test. Unfortunately, I'm in Philadelphia so I have no suggestions for a shop in LA.
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Customer: replied 4 years ago.
And one of the piston look kind of high passed the surface very very little when I run a blade across it bearly grabs

There might be more damage done to this engine than is worth fixing. It might be a better route to just get a used engine in good condition.

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Customer: replied 4 years ago.
After I check the berrings I will see if there is more damage if there is I will tell you what I see and you tell me if I should think about new engine
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Customer: replied 4 years ago.
One of the cylinders is chipped 1/4" in one corner And about 2 inch away from that chip there is another one about 1/2" size and scratches on the cylinder wall might be a crack I can't really tell, this engine had 130 miles now its trash the berrings were ok no scratches and was thought and secure
Also one cylinder is sticking out tiny bit crankshaft might be benth :-(
Thank you very much for your help
Yeah, its never good when you get a runaway. Sorry you didn't get lucky. Time to scrap that engine.
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Customer: replied 4 years ago.
I know , I paid 1500 for the truck spent another 2000 ended up with junk and 2 weeks of problem chasing :-) luck is on my side as always lol
Well better luck with the next engine!
Customer: replied 4 years ago.
Thank you!!!!
No problem!
Customer: replied 4 years ago.
I looked closer and the engine case is fine isn't it better to buy a rebuilt kit and new heads and doo a complete rebuilt it would cost around 2000$ and I would have a new engine instead of buying a hard to find engine in unknown condition

??? What do you think?
That's up to you, as long as you're confident in rebuilding it.
Customer: replied 4 years ago.
Like 2 hours after I sent this question I went on Craigslist I searched go gmc td and I found a complete engine for 600$. the guy told me tis will work on my truck so I bought this now. This is 97 6.5 td and my truck is a 93 td after inspecting it it looks like the block is little different thus was off a van and mine is a pickup.
Will I be able to install this on my truck?
Sorry, I don't know if that engine will work or not. I don't know the answer to that.
Customer: replied 4 years ago.
FYI I took the engine to machine shope I had oner 12 cracks on both heads thoughter, had a fixable crack on the case and needed new sleave in one cylinder barrings were ok normal use, 2 pistons were replaced becouse melted damage on the side only one glow plug is good and the rest were melted 2 injectors were melt damaged .
I bought a 97 6.5 from a van and mine is a pickup they told me I can use the heads but the intek bolt holes were in a different engle lol, so I got new heads , I can sell the 97 parts hopefully make some money , used injectors, glow plugs, flywheel and two pistons from it , and the rest need to be sold
Ok best of luck with the whole project!
Customer: replied 4 years ago.
Thank you
No problem!
Customer: replied 4 years ago.
I just rebuilt the engine and the turbo new heads ..stated the truck with wite smoke gets more at higher rpm..just went next to the tail-pipe to smell the smoke it smelled like burned oil? And there is about a a lot of black engine oil but I checked my dipstick and there is no oil in the engine before I started the truck I had more the recommended it was like half an inch pased the operating range on the dipstick, could this be from privies runaway? But after the runaway I drive the truck 15-20miles it did make black smoke at that time, why how would I get oil in my exhaust after rebuilding the engine,
The exhaust may still be loaded up with crap from the runaway. Blue smoke would be oil, Black is unburnt fuel, white could be incompletely burnt fuel if you are sure it is not steam from coolant.
Customer: replied 4 years ago.
Stupid me! I forgot to open the turbo drain and all the oil went to the intek.
How can I clean this without removing the heads?
Thank u!

Just make sure the oil level is correct and drive it. It will burn off. You don't want the oil overfilled or you run the chance of another runaway! You should be fine after that.
Customer: replied 4 years ago.
Ok it works without smoke
It shakes very little on park but when in drive and I let go the break without touching the gas pedal it bonuses/shakes a lot
Do you think it's the injection pump adjustment?
It could be, I'm not exactly familiar with the adjustments on that pump. I most likely has to be fuel related considering there's no ignition.

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