Post Rebuild Trouble - Crack the Case?

[a ron]

Hey guys,

I've been lurking the forums for a while and I really appreciate all of the helpful info you've posted. With the help of some of the posts here I was able to rebuild my top-end.

Trouble is now, I derped and lost a wrist pin clip in the engine, didn't know it, and it flew back up in the cylinder and scarred the cylinder and piston when I started it after the rebuild. It ran like new until that happened, which was like 5 minutes max. I used a leak-down test to determine that after my boner-induced-scarring of the cylinder, the cylinder/piston is leaking at about 60%.

I'm at a crossroad of sorts because I think I've retrieved the majority of the clip but I don't know for sure. It's just not possible to see the bottom of the engine where the crankshaft is. I have the engine out of the quad and I'm just sort of weighing my options. I'm tempted to re-bore the cylinder and pop in a new piston, but apparently the crankcase REALLY must be clean and free of contaminants, especially of the metal variety.

I'm just thinking there has to be a way to wash out the base of the crankcase. Maybe I can use kerosene to wash it out, turning it upside down etc? It's probably naive to think that I can get to the bottom of the crankcase without splitting the case, but splitting it it seems last resort.

Anyone have any suggestions on the best way to go on this? I appreciate any advice you guys have.

 

[dirtysquared]

I hate to be the bearer of bad news, but the only way to be 100% sure you have all debris out, is to split the cases and get it out.

It would suck 100 times worse if you do a bore and have another piece of metal take that new top end out also.

Start now, and you'll be done soon!

 

[speedyslyder]

how did you take out broken pieces??? example?

 

[a ron]

I hate to be the bearer of bad news, but the only way to be 100% sure you have all debris out, is to split the cases and get it out.

It would suck 100 times worse if you do a bore and have another piece of metal take that new top end out also.

Start now, and you'll be done soon!

Ya know, that's an excellent point - I would be really upset with myself if I burned up yet another cylinder. I think I'd commit seppuku.

how did you take out broken pieces??? example?

Good question! I found two pieces total; the clip was sheered and somehow both pieces were straightened. Both pieces were just setting on top of the crankcase partition, below the piston. I tossed the smaller piece in a fit of rage and self loathing, otherwise I'd measure the pieces and compare it to the other ring to see if I had all of it. :-/

Thanks guys!

 

[dirtysquared]

Ya know, that's an excellent point - I would be really upset with myself if I burned up yet another cylinder. I think I'd commit seppuku.

That was my point. Even if it works out, you don't want to have that doubt in the back of your mind all the time.

Its better to not take chances in this game.

 

[Fast6hand]

I hate to be the bearer of bad news, but the only way to be 100% sure you have all debris out, is to split the cases and get it out.

It would suck 100 times worse if you do a bore and have another piece of metal take that new top end out also.

Start now, and you'll be done soon!

I agree! Split them, clean them, rebuild and ride!

 

[a ron]

Alright, I'm going to crack it open. Is it possible to go at it just from the stator side? The side with the gears looks complicated. Can I avoid it?