Just a big headache

[dazedandconfused]

So I have a buddy that purchased a 383 stroker from another one of our freinds. That boy bought all top end parts and had a guy assemble the motor. Well fast forward to know we put it in my buddys truck and got it all running. He put maybe 12 miles on it and called me saying it aint running right and is smoking. So he hauls it to my house and it's mixing oil and coolant so I pulled it apart today to find a section of piston missing and 2 large cracks in #1 cylinder. I was expecting a blown head gasket. My theory is the guy who built it broke the top edge of the piston off and buttoned it up knowing it was gonna sit for a while. That was 5 years ago when it was built and has never been started until 2 months ago.

[dazedandconfused]

There is no sign of the piece of piston beating around in the cylinder or on the head/valves.

[BILTIT]

Ouch, I trust people/companies very little these days. Makes getting things done very frustrating.

[CumminsPower59]

that really sucks!

[dazedandconfused]

I've tried for years to get him to put a Cummins in this truck with no luck. Now he wants to throw all this money away and drop a Cummins in it. Here is a pic of the truck infront of my shop.

[ellis93]

That could be caused by all kinds of things dazed. I wouldn't be real quick to finger the dude that built it. Sucks none the less

[dazedandconfused]

There is no way that big of a chunk of piston disappeared without some sign of it exiting. There isn't a mark on the head, valve or anywhere else on that piston or cylinder. It's never made a sound when running either. Ellis what do you think happened to that chunk of piston?

[ellis93]

No marking on the combustion chambers or anything? I've seen stuff pass thru without much marking,espeicaly with large cam lifts.
Gotta think about shipping practices and how pistons are packaged too.
Is that cracks in the cylinders,bberry screen
If so I'd look for a skirt missing,won't be much of one on 383 pistons anyhow. Could have taken a nasty tumble. Could have been abad casting. Could have been a turd piston to start with.
IDK who it is that done the work but that seems like a lot of damage just from a missing piece of piston.

[dazedandconfused]

Here are a few other pics. I sprayed the piston with brake clean and wiped it off and has no signs of impact from a piston piece flying around in there. The same with the head which I wiped off and cleaned up with at red scotch bright. It has no marks on it either.



Now I've built over 75 engines over the years that have been blown up and cracked off smaller pieces of pistons that have destroyed heads. I still believe he knew it had a issue when he assembled it. The shop he works at has had many vehicles he has worked on come back with other damage due to shoty work.

[dazedandconfused]

No marking on the combustion chambers or anything? I've seen stuff pass thru without much marking,espeicaly with large cam lifts.
Gotta think about shipping practices and how pistons are packaged too.
Is that cracks in the cylinders,bberry screen
If so I'd look for a skirt missing,won't be much of one on 383 pistons anyhow. Could have taken a nasty tumble. Could have been abad casting. Could have been a turd piston to start with.
IDK who it is that done the work but that seems like a lot of damage just from a missing piece of piston.

Nope there isn't a mark one in the cylinder except the 2 cracks.

[142autox]

How was the motor stored for the 5 years it was not in service?

[dazedandconfused]

Oil pan was filled up and system primed with a drill. Exhaust and intake ports were taped up and the plugs were pulled and cylinders were fogged with an aerosole used for storing engines. Oil was changed every year and re fogged is what I was told.

[Mark Nixon]

High compression + thin cylinders + detonation = split cylinder.

I'd say sleeve it, but you'd want to sonic check the rest of it before pouring more $$ into it.
That's IF that cylinder is even sleeve-able.

As far as the missing chunk, it likely got broken up and sent out the exhaust.

Mark.

[142autox]

Even with those precautions rings could still freeze to the cylinder walls, if the even actually did those. I wouldn't trust any 5 year idle motor unless it was in my possession and I religiously oiled and rotated the motor.

That broken piece most likely came off in small pieces after several hunded thousand revolutions. I would be expecting to see evidence marks too, but as Ellis said they can go strait through an exhaust port.

[Mark Nixon]

Oh, yeah, you're likely looking at a broken skirt, too, because the pistion likely tipped when a skirt broke and if you look at where the chunk looks like it was broken out, it likely tipped the piston TOWARDS the top and broke the chunk out at the weakest, thinnest point, the valve trough.
Did he use Hypers?
We all know how brittle those POS hypereutectic pistons are, which is why the skirt will have broken, if hypers were used.

Detonation will have played a role, IMO.

Mark.