[Buster177]

I just purchased this machine with seller saying it had a bad knock in the engine and was not going to repair it. I got it at a great deal thinking I would be able to fix the knock easily. I am pretty sure it is a connecting rod bearing and plan to remove the engine and pull the bottom cover and see what is up. If only bearings and I can polish everything back into good shape, would a set of bearings be all that i need to stick in it? A question I have is, why would a rod bearing go bad? I can't find anything that states these engines have this problem so that makes me feel better. What reasons are known for this thing kicking a bearing like that? Any help on this would be greatly appreciated!!!!!

New Member,
Buster177

 

[mtgott]

Pretty hard to guess what parts might be needed untill you get it torn down to check damage

 

[buster177win]

Well I have gotten it torn down. Number one rod bearing beaten all the way out and heavily discolored. I also find that this engine has blown this rod before as it apparently came apart and cracked the case and ground away at a few spots. Someone epoxied the crack and apparently put in a new rod and bearing and now it has eaten the bearing out of it again. I am attempting to surface the crank back round but I am pretty sure the journal will end up ten thousands smaller than the good journal. Does anyone know if the bearings offered will make up that difference? I can't find what size the bearings actually are for the different colors offered. I found a lot of metal trash in the crank oil gallies and that may have starved it for oil from the previous explosion. If I can get the proper clearance on the bad journal I will be cleaning, and putting back together. Hopefully it will hold this time.

 

[Buster177]

You know I have been thinking. Seems like a lot of identifying a problem and things to check or was checked but not a lot of follow up with what actually repaired things. I was going to give up and move on but then I thought, why be what you don't like? So I am going to update my situations in a really short blurb and hope it helps someone along the way. Hopefully more than Toyman will read and respond as he was the only one originally.
Tried to save the rod and crank with a lot of sanding/grinding and micrometer readings. Didn't work, spun same bearing first start up.
Ordered new rod and crank and connecting rod bearings. Already honed and installed new piston rings on the first trip through.
Made super sure the oil cooler and lines were full of oil before starting up and shutting off in about 5 seconds and check oil level on dipstick. added oil till it stayed slightly above full and then let it warm up. Seems fine!!!!!
Ordered adapters and put on 29 inch bighorns off of a polaris 1000. Looks great!!!!
Cleaned up and took to WV on the weekend of September 8th, black bear lodge!
Ran great on trails for about 2 hours and developed a high idle that would not let me turn through the corners. Had to shut key off to keep from being pushed off the mountain or burning my belt. Could not shift to neutral due to pressure on the gears.
Fortunately it broke down near road to Mud pit. Ran back with friend, got truck and trailer, picked it up and then jumped in with my friend and rode with him. Too disgusted to take apart there.
After high idle it developed a loping idle instead of a high idle. Checked all connections, changed plugs, still the same.
Took throttle body off and while cleaning noticed that there is a set screw for butterfly opening. There is also a cross drilled and tapped hole for a locking screw to keep that one from moving. That screw is gone. Vertical screw had vibrated down and began holding the butterfly open too much.
Set back to just touching in the bore and put new screw in to lock in place.
Put it back on the cat without the air box and filter.
re-synced the computer to the new settings and fired it up!
Idles as it should and I am ever grateful that was all it was. Gonna readjust my shift linkage where I may have been jerking on way too hard in the I need to stop panic mode.
I will try it again. I need some reliability confidence in this thing and I hope it gives me just that.
I have the springs set as soft as possible but it still seemed a little choppy on the small bumps. What tire pressure is best for the smoothest ride in a machine like this?
Thanks and I hope something in this may help someone else.

 

[70Bones]

Glad to hear you have been able to troubleshoot and fix it! I have the same machine, with about 3000 miles, it works flawlessly other than it recently started using a bit of oil, maybe 1/2 cup during a 100 mile, hard and fast and very dusty riding day. I found dust on the FI inlet butterfly valve, even though the filter is well oiled and sealed...... If it gets any worse, I'll do like you and put new rings in it.
Keep us up to date on how the buggy works out!

 

[Sak kitty]

Sounds like you’ve got it on the run to being a reliable machine again, maybe post up where you came up with parts like bearings and rings and some part numbers to help others.

 

[Buster177]

Sounds like you’ve got it on the run to being a reliable machine again, maybe post up where you came up with parts like bearings and rings and some part numbers to help others.

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