[Pfunk5309]

Hello fellow riders. I have a problem I’m looking to pick someone’s brain on.
Rancher was smoking a little and I discovered my intake valve seal was leaking. I also found a little pitting in cylinder wall so I decided to do a full top end rebuild. After first rebuild It started smoking after 4 or 5 hours so I broke it back down and found the piston was riding the cylinder wall on the exhaust side and scared it allowing oil to get in combustion chamber. Hoping the hone was bad I ordered a stock cylinder and piston and did it again. After getting the cylinder on I noticed the piston is still leaning towards that exhaust side, (see attached picture.) i’m worried if I put this thing back together and start it it’s going to scar the new cylinder again. I have no up and down play in the rod.

Anyone have any ideas what would cause this? I’ve tried different clock positions with the rings and seems like no matter what I do it leans to that side.

Any ideas or help will be greatly appreciated!

 

[Woodeye]

Anyone have any ideas what would cause this?

A bent connecting rod?

 

[Pfunk5309]

Yea that’s the only thing I can think of, I’m hoping that’s not the case. It’s hard for me to comprehend, the motor never really went through anything traumatic. Maybe one swamp episode. Doesn’t appear to be bent, (attach pic of rod.)

 

[fishfiles]

egg shaped bore cause by a loose connecting rod , maybe , you honed the cylinder from your post ? , and that was't good enough, maybe if you fell the connecting rod is ok then bore it this time and go with anew piston , G+h does a good job

 

[Pfunk5309]

1st cylinder was bored 10 over with Numara piston. . This one is a new Honda stock cylinder and piston. Both are rubbing cylinder wall the same.

 

[SlammedRanger]

Thats one bent rod. Uneven cylinder wear was the most sure thing clue. The pictures of the piston in cylinder just confirms it.

 

[shadetree]

rod is bent. it hydro locked, bent the rod when it got sunk.

 

[Pfunk5309]

Bummer. Guess I should have just left it alone. I have an 85 big red that drinks swamp water and still runs perfect. These newer machines are done after one time.

 

[shadetree]

Bummer. Guess I should have just left it alone.

tear it all the way down, buy a new rod, press old one off, new rod back on. look around for a machine shop that might do this for ya. or, buy a new crank, or, take a gamble on a used crank from ebay.

 

[Pfunk5309]

Yea roger that. Will See if I can find the whole assembly. Or check and see if insurance will cover it. Thanks y’all.

 

[shadetree]

Yea roger that. Will See if I can find the whole assembly. Or check and see if insurance will cover it. Thanks y’all.

if you tell your insurance you sank it, and caused this damage ?, i'd bet my last dollar they won't cover you !!!.

 

[Jeepwm69]

If it's a 420 nobody makes a rod kit for it yet.

And yeah, I agree that the rod must be tweaked. I had the exact same scenario with the 08 I bought, and when I put a new used crank that was good the thing was perfect.

See page 6...

http://www.hondaatvforums.net/forums/builds-projects-diy/56009-08-rancher-i-picked-up-6.html