Brown Truck Under the Knife Project - Engine

[6 Nebraska IDIs]

The only thing abnormal about the radiator pressure that I noticed when it ran last was that the radiator appeared to be cool enough to have lost all of its pressure and it hadn't the hoses were still pressurized. So I pulled the radiator cap and ran it with the cap off to see if there were any bubbles coming up and there were none so I wrote it off to the fact that I am running a 22psi radiator cap and for whatever reason the pressure was not released. It did run warmer coming home that day the incident happened than it had been running. But who can say what normal anything is for an engine when you've only ran it less than 100 miles.

 

[1320Cummins]

You gotta have a cracked valve. Pull the glow plug from #8 rotate motor so that both valves are closed and apply shop air to the glow plug hole. Where is the air going? That will tell you whats going on. I am leaning toward bad exhaust valve.
Good luck with it and hang in there My s-1600 put me through hell when I rebuilt the motor. I owned the truck for all of two hours before it let go. two weeks after the rebuild I broke a wrist pin Not exactly starting off on a good foot. You will get it, and it will feel so damn good!!

 

[dyoung14]

I was just about to sugjest the shop air down the glow plug hole

 

[6 Nebraska IDIs]

Yea, I'm leaning more that direction too because as I pointed out and Gary confirmed for me, a hole in the piston would have made it impossible for me to drive it the 4 miles home that I drove it after the incident happened.
So. Theoretical question. Say I pull the head and its a broken valve. There is less than 100 miles on those heads and they were supposed to be completely gone through, valves checked for stress fractures and any other needs for replacement and replaced accordingly. (I already asked Calvin this and he told me good luck, which is probably the truth. But I'd like to know what you guys think.) Should the machinist be accountable for everything required to fix the problem he either caused by not machining the valve correctly, dropping it, or he should have at least caught? Let me know what your honest opinions are. But personally with less than 100 miles on ANYTHING there should be some sort of recourse IMO. That's just ridiculous. But like I said let me know your honest opinion. Should he make this right?

 

[dyoung14]

Hmmm well lets find out what the damage is first before we point fingers, did you put new valves in it when you rebuilt it?

 

[1320Cummins]

Here are some of my s-1600 carnage pics. The valve is #6 exhaust, smaller valve is from a D15 Honda. Some split and spun main bearings, as well as my broken wrist pin.
Edit: The smaller piston is from the same D15 about a week after rebuilding the head.

 

[6 Nebraska IDIs]

HOLY CRAP MAN! Please dont show me those. God I don't want to think about what my poor brand new turbo looks like after some of those missing pieces ran through it. Oh it makes me want to cry!

 

[dyoung14]

Here are some of my s-1600 carnage pics. The valve is #6 exhaust, smaller valve is from a D15 Honda. Some split and spun main bearings, as well as my broken wrist pin.

What caused that to happen in the idi?

 

[1320Cummins]

I am not to sure about the split bearings. Best I can figure is that the motor was run with water in the oil as I found too much rust on things like push rods and a few other parts. The bearings also show signs of getting hot which is directly tied to lubrication issues. The valve let go due to a combination of high EGT and being over spun. All of the above was done long before I owned the truck. I broke the wrist pin, and believe it to be defective.

 

[dyoung14]

over spun as in over rev? i havent had any problems with mine and i tach the **** out of mine alot

 

[1320Cummins]

HOLY CRAP MAN! Please dont show me those. God I don't want to think about what my poor brand new turbo looks like after some of those missing pieces ran through it. Oh it makes me want to cry!

I bet your turbo is fine. You should check it though. When my valve let go it sounded like small gravel beating against the fiber glass hood of the truck. My ATS Garret turbo had a couple of slightly bent blades. I was going to run the turbo as is but I had the HY-35 laying around so it was just too tempting!

 

[1320Cummins]

over spun as in over rev? i havent had any problems with mine and i tach the **** out of mine alot

I know this thing was turnin some RPM because every piston shows valve contact.

 

[dyoung14]

I know this thing was turnin some RPM because every piston shows valve contact.

you sure the clearences werent just too tight cause icanfixall said on his origanal motor i think the first one he built that burned down every piston had a spot were the valves kinda kissed the piston just enough to leave a mark but not enough to cause any real damage

 

[6 Nebraska IDIs]

But see thats the whole thing. My exhaust temps were right around 800* which is nothing, and I was running under 2500rpm which is also nothing. I've wound out the POS 6.9 in my moms crew cab (the one that had 4 gallons of water in it when we picked it up) to 3800rpm at 1250*egt just trying my best to blow that POS up and it wouldn't do it. For just being machined and checked for any imperfections there shouldn't be any problems whatsoever running it at 2500 even at 1250*, neither of which I did.

I'm trying to get this engine to run as most efficiently as possible, I won't be running a damaged turbo. If its damaged it will be fixed. Especially since that turbo has less than 100 miles on it as well.

 

[1320Cummins]

you sure the clearences werent just too tight cause icanfixall said on his origanal motor i think the first one he built that burned down every piston had a spot were the valves kinda kissed the piston just enough to leave a mark but not enough to cause any real damage

I have no idea, and at this point dont really care. When you take into consideration the weight of the truck, and the strong agressive clutch, I would not put it past a new driver to hit the wrong gear and send this thing spining to the moon.