2012 rush 800 blown up help

R

raceinsnow

New member
They have bad ,soft pistons. After so many miles the top ring land opens up and catches on the exhaust port and scores the cylinder,very common problem. Some people believe that it could be a fouled plug or something else and continue to run the motor and cause more damage,I am not saying that is what happened but is common. You are not going to like what I am going to suggest, I would replace the crank with a reman one, have the cylinder repaired and use RK tech pistons. Dont forget to replace the fuel filter.
 
P

Polarisrun123

New member
ezra said:
http://www.2strokeheads.com/Polarispistons.htm
I would do rk tec

u say a chunk came out did it go out the pipe or down in to the case ?
if it went down or u don't know it could be a lot worse than a top end.
I have seen 2 800s a 11 and 12 with good size crack to actual holes in the case from piston skirt trying to spin with the crank lobe.
Click to expand...

I'm not an expert on engines by any means but it looks like that chunk must have just a blown out the exhaust because there was not any scratches or anything on the cylinder wall and the rings were in tacked on that side is it possible that chunk has been missing for a long time and I've just been losing power and not noticed it until the ring broke on the other side causing damage to the cylinder and only allowing the sled to run on one cylinder ?

- - - Updated - - -

raceinsnow said:
They have bad ,soft pistons. After so many miles the top ring land opens up and catches on the exhaust port and scores the cylinder,very common problem. Some people believe that it could be a fouled plug or something else and continue to run the motor and cause more damage,I am not saying that is what happened but is common. You are not going to like what I am going to suggest, I would replace the crank with a reman one, have the cylinder repaired and use RK tech pistons. Dont forget to replace the fuel filter.
Click to expand...

That's exactly what mine did! But do they both go at the same time?
 
P

polarisrider1

New member
markshop said:
Was there any year that Polaris built a good 800 that would stay together for more than 5000 miles? Seems we have been hearing about the 800 motors falling apart for 10 or more years.
Click to expand...

My 01 800 XCSP had 8800 miles on it when I sold it to my brother in law. He has 17,800 miles on it. 3rd track. Still running. Blue cap poo oil.
 
Last edited:
E

ezra

Well-known member
Polarisrun123 said:
I'm not an expert on engines by any means but it looks like that chunk must have just a blown out the exhaust because there was not any scratches or anything on the cylinder wall and the rings were in tacked on that side is it possible that chunk has been missing for a long time and I've just been losing power and not noticed it until the ring broke on the other side causing damage to the cylinder and only allowing the sled to run on one cylinder ?

- - - Updated - - -
prob more likely the 1 side lost the ring caused a big vibration kind of thing and the other piston was already old and fatigued and the jolts caused the break . just a theory but deff possibility. at the point u are at it will cost u but I would have new crank seals put in and have the crank diagnosed buy a crank guy . dont know what parts u are from but I am in west metro twin city's MN I know a top notch crank guy .others on here prob know guys close to u and will chime in if u ask. btw your dealer prob sends there crank work out



That's exactly what mine did! But do they both go at the same time?
Click to expand...
tt
 
S

SLED_DOCTOR

Member
"They have bad ,soft pistons. After so many miles the top ring land opens up and catches on the exhaust port and scores the cylinder,very common problem"
Just want to clarify this comment. The pistons may be bad...but they are not soft. These engines use cast pistons and are most likely harder than the RK or BP replacements. Hard enough (brittle enough) that the skirts break and don't bend. I have the same engine with 2800 miles, all stock and original pistons. It is just a matter of time so I will most likely tear it down this Summer and refresh the top end.
 
Last edited:
H

Hoosier

Well-known member
ezra said:
http://www.2strokeheads.com/Polarispistons.htm
I would do rk tec

u say a chunk came out did it go out the pipe or down in to the case ?
if it went down or u don't know it could be a lot worse than a top end.
I have seen 2 800s a 11 and 12 with good size crack to actual holes in the case from piston skirt trying to spin with the crank lobe.
Click to expand...

Does that kit really only cost $375? Why can't Polaris make it right the 1st time? Certainly they know how to make a piston. Something to do with the EPA?
 
E

ezra

Well-known member
a bud called me asked me to come over to check something out this AM.
2013 800 switch back with the I think 136 and rack in back what ever that is called.
3980 all groomed trail mi. took out both jugs and crank case
 
R

raceinsnow

New member
ezra said:
a bud called me asked me to come over to check something out this AM.
2013 800 switch back with the I think 136 and rack in back what ever that is called.
3980 all groomed trail mi. took out both jugs and crank case
Click to expand...

That one sounds like the cylinder skirt broke off.
 
E

ezra

Well-known member
yep deff a skirt worse part I was trying to tell him to drop in a set of rt tek pistons this fall but he was insistent that the motors were fixed .
 
You must log in or register to reply here.
Top