Hole in Piston, Busted Rings, etc??/Question

157 Views 6 Replies 3 Participants Last post by stephenz, 9 d ago

stephenz

Discussion Starter · 11 d ago

Short story, I think I have a hole in my #7 piston, however, wouldn't I get a misfire code for #7 cylinder? Was coming home from Florida doing around 72mph with my 14k trailer, only had a 3900lbs truck on the trailer, so total load of trailer and cargo may have been around 7-8k lbs. total (+Truck Weight). Wasn't dogging the truck, had it turned down to 1 on my SOTF, which even on a regular day 1 isn't getting you anywhere fast anytime soon. I've seen the pictures of where they blow out on the bowl and right above the wrist pin, but for some odd reason, the truck just starts too good to have a hole in my opinion (Could be wrong, hope I'm not). Truck has a light haze at idle, compared to the videos I've seen where the trucks are just bellowing white smoke out as if they are running away, just has a rough idle, truck only smokes if you were to give it acceleration. The videos I seen where there was a hole/crack the trucks are completely bellowing white smoke out at an idle, and at an acceleration.

There was oil in Cylinder 8 and Cylinder 7 when I took those corresponding glow plugs out, I turned the truck over for a little bit, didn't get any oil back in the cylinders, had oil coming out of the turbo (thought the seals were shot), have a little bit of play that I think is too much on the turbo.

However, this is where it gets bothersome at. When you take the glow plug out of the #7 Cylinder (Back Driver Side, I'm an idiot, but not that big of an idiot). It sounds like metal scraping metal. Haven't taken a stethoscope to listen directly to determine is it the cylinder, valve, push rod, etc?... However should be able to determine if there is a hole or not in the piston with the bore scope later this evening.

I've got 420-430 psi in each cylinder, while #7 has 0.

With all 8 glow plugs taken out, and then reinserting 7 or my compression gauge, I had a buddy turn the truck over, and I could feel air coming out of the exhaust, could that insinuate the possibility of either a bent push rod, valve lashing, bent valve, versus having a hole/crack in the piston?

Will be throwing a bore scope through injector hole later this evening when I get in from work, just trying to get my ducks in a row. And obtain some highly educated guesses.

If there's a hole, so be it, just ain't my year, I'll yank it, have it bored over if I have to and start the build that's been planned for a few years now...

Thanks,
Stephen

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OkDually

· #2 · 11 d ago

Welcome

Please tell us more about the vehicle ( Year, Make, Model ) and list all mods

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stephenz

Discussion Starter · #3 · 11 d ago

OkDually said:
Welcome

Please tell us more about the vehicle ( Year, Make, Model ) and list all mods

Woops thought I posted it in signature forgot to hit submit sorry.

2016 Chevy Silverado
Fass 165 - Filters changed every 10k miles - Engine Bay Filter deleted since 2018 (No Issues)
Deleted - SOTF - Have been running the same tunes since 2017, can't remember off the top of my head the name, but they aren't coal rollers if that helps.
CP3 Conversion - Fleece 650 - After warranty ended, decided it was time to be proactive instead of reactive. (FPR and DFPR are in line with each other)
Juggernaught 750 from Inglewood - Lost Trans last year, decided to have Mike L and his guys build me one. - External Filter Changed every 10k miles when I do my Fuel Filters
Stock Injectors (Balance rates went crazy when this incident happened) I imagine oil was the cause in the cylinders to throw the balance rates off an absurd amount.

I like to think I've taken pretty good care of this truck compared to about 20+ years ago when I was trying to impress women.

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OkDually

· #4 · 11 d ago

stephenz said:
Woops thought I posted it in signature forgot to hit submit sorry.

2016 Chevy Silverado
Fass 165 - Filters changed every 10k miles - Engine Bay Filter deleted since 2018 (No Issues)
Deleted - SOTF - Have been running the same tunes since 2017, can't remember off the top of my head the name, but they aren't coal rollers if that helps.
CP3 Conversion - Fleece 650 - After warranty ended, decided it was time to be proactive instead of reactive. (FPR and DFPR are in line with each other)
Juggernaught 750 from Inglewood - Lost Trans last year, decided to have Mike L and his guys build me one. - External Filter Changed every 10k miles when I do my Fuel Filters
Stock Injectors (Balance rates went crazy when this incident happened) I imagine oil was the cause in the cylinders to throw the balance rates off an absurd amount.

I like to think I've taken pretty good care of this truck compared to about 20+ years ago when I was trying to impress women.

I think you're on the right track. I am leaning on a busted valve, bent pushrod issue...

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stephenz

Discussion Starter · #5 · 10 d ago

OkDually said:
I think you're on the right track. I am leaning on a busted valve, bent pushrod issue...

I hope it's a valve, but my luck we're going to have that busted piston lol. Wife's already got me in the dog house, was picking up a 86 Scottsdale Squarebody when this happened, so she was already irritated that I went on a saturday to get the truck instead of spend some family time. So might as well tack it on while she's upset, right?

On a side note, my EGT's never got above 700* F for the most part even during pulling a trailer, I think i've managed to stay around the 550 mark, I have the alerts set on my Insight Monitor, and they never activated, even double checked to make sure they were activated. That being said isn't the melting point like 1200ish on Aluminum? So we should be theoretically safe in that vicinity. Who knows, but ones thing is for sure I will know today...

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Oregonnovaguy

· #6 · 9 d ago

For what it’s worth, I’ve never burned a hole in a diesel piston, but many years ago, I burned a hole in a gas engine piston (more than once). The cloud of blue smoke was so dense you couldn’t see the car behind me.

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stephenz

Discussion Starter · #7 · 9 d ago

Oregonnovaguy said:
For what it’s worth, I’ve never burned a hole in a diesel piston, but many years ago, I burned a hole in a gas engine piston (more than once). The cloud of blue smoke was so dense you couldn’t see the car behind me.

Update: Cracked #7 piston, but no misfire or diesel in the crank case…clear as day with bore scope. Things that throw you for a loop I guess. Will have it pulled by Memorial Day, on the stand ready for the next step, if cylinder is scored, most likely going to see about going .20” over, doing all near bearings, push rods and valves/springs while it’s out, along with a 64mm Turbo, most likely going to throw at bare minimum +50 injectors as well, depends on what the wife has to say. We’ve discussed if the cylinder isn’t scored just doing the one piston and bringing to the stealer ship and trading it in on a new L5P. But that’s not something I absolutely want to do considering I don’t have a note and haven’t had one for a few years now. Until then driving my trusty/bot so trusty LB7. Lol

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