Well here is the first major update. I took the head and cylinder off today, everything was perfect down to the piston. Something let loose in the bottom half and the is a chuck of it wedged in between the crank shaft and the counter balancer [img]i/expressions/face-icon-small-sad.gif[/img] The crank is pretty beat up. The underside of the piston has some dings in it too. The rod is the only thing that appears to have no damage at all down there. The sleeve in the clyinder is perfect except on little ding on the very bottom where it tapers off. So at the least it looks like I need whatever broke, the crank if its not fixable, a piston, maybe a rod and alot of gaskets! Not good. I still have to split the cases to see what else is damaged. What do you guys think about the crank?? it has alot of dings, I'm sure at the very least it will need to be trued, but may need replaced. shoud I just get a new rod to to be safe?
While I am in there I think this is my plan.......
All needed parts, high comp piston stock bore(I think), Cam, and maybe port and polish job. What else would you guys add to that....

Thanks for any help.....

P.S. Thats the last time anyone but me is riding my quad!!!! This may not have happened with me on it..

 

I think you could be right about it not happening if you only rode it. It seems when some people ride these things they lug it badly. It is like the piston bangs so hard when they are lugging it, that something could brake. If I were a betting man ( I only bet when I know I'll win), I would say it was lugged in a higher gear. These things turn 9k rpms so I think to slow is bad. JMO

 

From what is sounds like that is what happened. I guess he was trying to do dounuts is the snow in to high a gear and it was catching traction while sliding backwards or close to it. What do you think would be the part that let loose and is now stuck in my crank?? Man I should have never left the field while he was on it, that was the first time I let anyone on it without me being right there. I am sure thats what did it now. LESSON learned, now I just have to pay for it. I am thinking about just finding a used engine for now and then fixing mine later. Anyone know where I can find a whole engine or most of one at a decent price???

 

Damn man that sucks. By the way, that is the same thing I am doing.....11:1 stock bore, stage 2 cam, you have to get titanium valve springs with the stage 2 cam, and a port and polish. i'm really looking forward to the new power. [img]i/expressions/face-icon-small-smile.gif[/img]

 

If you have to split the cases anyhow I'd have them bored so you can add a 105mm piston later. Also buy a carrillo rod direct from carrillo, they should have more in a few weeks. Take it to an experienced shop for the crank work. If you can afford it at least go with a 686 and hotcams stage 2. If not rebuild it with the stock components but the aftermarket rod and welded/trued crank. Its a solid basis for future builds and wont cost alot more than the stock rebuild.

 

Do you think I will need a new crank due to the dings it took?? And how much is the carrillo rod? Once I get the bottom end beefed up I will probably just do a high compression stock bore for now till the wallet recovers, then build a nice 686 in the future! Where is a good place to start looking into the crank work/purchase?

 

How can you damage your engine when you're in a too high gear?

 

Hey, keep us updated with what the prices and stuff are going to run you with your stock bore piston, cam, valve springs, and whatever else you do.

 

???

 

I had another post started on this as well, but I will update this one for those who missed the other. I am collecting the cash right now to send the motor off and hopefully before to long I will be a proud owner of a Craycraft 686. Updates will come as I have them.
Here is the needed.......
Crank reworked
Misc parts that need replaced with the crank
New rod (aftermarket)
whatever let loose be fixed
Piston
Other internal need checked for damage
Timing chain (possible)
And of corse all the gaskets and seals that are messed up

Here is what I want to add since I am already in the engine......
port and polish head
JE 102mm 686 piston
stage 1 cam
Clutch-- The stocker like to slip when I really need to use it
and what ever else comes up that needs attention

Father in the future I'm also gonna get aftermarket carbs, not sure on FCR's or Edlebrock yet.