Burnt piston

YOUNG GUNS15

YOUNG GUNS15

Im AWESOME!!!!
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Sep 24, 2009
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I pulled my head to install used some valves I bought from a member on here. The tops of my valve stems are beat pretty good from running high rpm without 60# springs. I have 60# springs now but i ran as high as 3600-3800rpm without them IIRC. So in the process im looking at my pistons and cylinder walls. and noticed something a little goofy about number 3? Ive searched through several melted CR's pics an 12 valves and really haven't found what I'm looking for.

Is this bad?


148426_1706350786829_1479824364_1740209_2443735_n.jpg


Edge of #3 looks a little suspicious. So far its the only piston like that.

Thanks
 
Im sure you numbered your injectors to the corrisponding cly so have that one pop tested. piston looks ok from what I can see, fuel delivery is a different case
 
They are DDP 2's at 21* timing. Maybe a year or so old. I knew i would be out of the bowl at that kind of timing. Hazed in the morning but was okay other than that.

Edit: yes i did number them.
 
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meanwhile, the other piston looks the same...

DDP's have the marine spray pattern IIRC... 21* will put them way out of the bowl, which you're seeing there...

your pistons are fine. get some better injectors :cool:
 
The edge is starting to melt another 5k and it's toast if you don't fix the problem! Not sure if that piston is savable once they start to melt the structure is degraded and failure is coming! Too much fuel in that cylinder. What engine is this? 12v 95?
 
Its a 94 12 valve. Im working on getting better pictures.

On edit: Forrest, im looking at the outer edge of the piston not the edge of the bowl.
 
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Failed injector causes burnt piston is my thought ???
 
Cylinder walls look great! gasket was just fine! Injectors on the other hand are another story...
 
Looks like the injector was shooting fuel only on the side that melted! See the spray pattern! Anyway at least you can fix the head now and the piston if you want! That injector looks like crap serious leakage there huh! Did you steam clean the engine a while back? How long have they been in there?
 
dangerous06 said:
Looks like the injector was shooting fuel only on the side that melted! See the spray pattern! Anyway at least you can fix the head now and the piston if you want! That injector looks like crap serious leakage there huh! Did you steam clean the engine a while back? How long have they been in there?
Click to expand...

They are just over a year old. I have the receipt from them I'll check that out when I can get out to the shop again.

I'll know whats going on with the injectors in a week or two.
 
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