Grenade in my engine!!!

[BiggieSOMD]

Well, I was pulling my head thinking that it just seized and I was gonna get some porting and a bore done. Well, I found some shrapnel near the crank assembly. I haven't tore it all down, but I'm gonna need to. I'm leaving for class in about 5 min, so I will be back around 7:30 for better pics. Any guesses of what went boom?

Symptoms
-It ran lean before it broke
-Shrapnel in under crank assembly
-Was going WOT when it happened
-Kick starter wont move at all


Ken, I still want to get that work done, just I wont be able to at the moment since I found this out.

Here is a quick cell phone pic of the shrapnel

 

[Whitty21]

piston skirt blow up? how long was it running? did you instal the piston backwards, were you running really lean?

 

[BiggieSOMD]

Forgot my english class had computers, so I was running super lean, and I will check the piston for forward facing. However I ran this all summer, the last owner said it had a fresh top end. I will get more pics when I get home, the piston looked fried however. I am debating how much all the work will cost, or how much another engine will cost.

Edit:Oh and it does not like going into neutral as of the day it happened, I did check the oil and it was fine

 

[Awk08]

yep, looks like the piston skirt, usually the exhaust side ????
and pieces are jammed between the crank and case, and hopefully didnt damage the cases down in there, gonna need to split them cases, or my usual solution is just send the whole thing to ken, remember his slogan on his website...................
"i wanna make it my problem" !!!!!!!!!!
i tried the do it yourself route once on my sons bike, just to see if i could, and i can, except it only lasted one season, then the crank went, so it ended up at kens anyway, which woulda saved me a few hundred bucks in the end if i'd have left it to the professionals in the first place

 

[BiggieSOMD]

Crap, cheaper to just get a used bottom end. Looks like I am sending Ken some more PMs

 

[Awk08]

someone else just posted a "cheap bottom end" in the good deals thread today, but then your takin someone elses word for it, again,
and crossin your fingers you didnt just waste more loot, when that one grenades, i'd just have ken rebuild the one you have, then you'll know what ya have, and that won't be a busted motor again in a few months

 

[BiggieSOMD]

Opps, didn't mean to word it like that. I was asking if it was cheaper. I guess I am going to have to save up another pay check. 2 more weeks, 2 more weeks...

 

[YFS101]

thats why you dont run them below 115 psi ....

 

[Awk08]

he said it ran lean, most likely from an airleak or poorly jetted, not low compression

 

[BiggieSOMD]

I would just say poor maintenance in general, I bought it as a shiny turd. So I ran it like it was my b****, and now I am paying for it. Lessons learned the hard way

 

[YFS101]

pistons usually break from slapping around in the bore.

if it was lean it would have melted it and or burt a hole in the top

 

[N8tsNastyBlasty]

if it was the piston melting the evidence is all over the plug with grey metal particles accompanied by a hole right in the middle. Ive had them fail on the edge of the piston above the rings but chunks that size have to be from clearance issues waisting the skirt like yfs101 said. I've done both on the quest of blasterdom.

 

[BiggieSOMD]

Well, I got home and went to look at my piston, I don't know if I didn't see it earlier since I was rushing to get to class. My piston is basically missing from the pin down. Not good, so I am thinking I am going to send out the cylinder and what nots to Ken. Then split the case myself, scary but I think I can handle it.

The worst thing is that I am missing alot of metal, so I need to really look close for cracks in the cases.

 

[BiggieSOMD]

This sucks

 

[slickerthanyou]

Great pic for the wall of shame! we all have one or two or three...

 

[scotj77]

or four with a couple cranks ta boot.

 

[Drifz1]

looks like piston slap to?

 

[NEONNIGHT34609]

u got more pieces in there then you found. getting it all out is the FUN part.

 

[UncagedShadow]

Hopefully you ge tlucky man. I bought my blaster for 300 bucks not running and not knowing what was wrong. It was just locked up. The piston looked exactly like that. I pulled the jug off and tipped the whole quad upside down and flushed the bottom end with water then drained it and used about a whole can of wd40 to remove all the water. Then i got a new piston and decided to take a chance. I checked the crank and it was fine from what i could tell. I popped the new piston in there and fired here up. Ran the tranny oil leakin from overfilling it out then she ran perfect from jetting here correctly. But i would not recommend this unless you feel safe pulling the bottom end apart if it does f*** up.

 

[BiggieSOMD]

My crank is messed up, so it might tund after cleaning, but I need to disassemble it it completely.