Jorg Jorgenson
Active VIP Member
Hey guys, so at the beginning of this summer some of you may remember my first post as I had just purchased a 2011 RZR 800s. Had a flawless summer except for the over the September long weekend when my brother was out riding and said it started to occasionally drop out on one cylinder. They would turn the machine off to let it cool down, turn it back on and get a few more km's down the trail before it would start happening again. Sometimes wiggling the plug cap/wires would help (so they say, as I was not there). Had to limp it back for a good hour to the cabin like this. I have since taken the machine apart and have done the following tests w/ results below:
The MAG (more towards the back of the machine) side plug was soaked and black (it had been sitting and not running for a few weeks). The PTO side (more towards the front of the machine) was dry and white. So already both not ideal cases. bought new NGK plugs right away and started it to get the machine up to temp before driving. After a few minutes of driving, it would gradually lose one cylinder firing. I left it idle and pulled the spark plug caps off to discover that it was the MAG side that would drop out (which matches up with the soaked plug). I switched the spark plug wires that go from the coil to the plugs around to see if the issue followed the wires or the cylinder & performed the same test. It remained the MAG side that would not fire after getting up to operating temp. I then tried switching around the plug caps only, leaving them connected to the coil as they were originally, just to see if if the problem would remain on the MAG side or switch to the PTO side assuming I have an issue with the coil. The machine wouldn't fire in this condition due to the timing now being off as they are set up from factory to not be switched around. Was worth a try I thought.
I then did a compression test to see if there was something fundamentally wrong with one of the cylinders. Surprisingly, the MAG side checked out as about 172psi and the PTO side was 150psi. So I now feel like I have another issue to deal with once I get the MAG side firing again!
Has anyone else had a similar condition happen? I've done some research and it sounds like an almost exact situation where it turned out to be a bad coil. I currently have new spark plug wires/caps on order and a new coil to try sometime next week. Any advice/suggestions are welcome! Trying to get this fixed to I can park it and focus on getting the sled back together lol.
Cheers,
Jorg
The MAG (more towards the back of the machine) side plug was soaked and black (it had been sitting and not running for a few weeks). The PTO side (more towards the front of the machine) was dry and white. So already both not ideal cases. bought new NGK plugs right away and started it to get the machine up to temp before driving. After a few minutes of driving, it would gradually lose one cylinder firing. I left it idle and pulled the spark plug caps off to discover that it was the MAG side that would drop out (which matches up with the soaked plug). I switched the spark plug wires that go from the coil to the plugs around to see if the issue followed the wires or the cylinder & performed the same test. It remained the MAG side that would not fire after getting up to operating temp. I then tried switching around the plug caps only, leaving them connected to the coil as they were originally, just to see if if the problem would remain on the MAG side or switch to the PTO side assuming I have an issue with the coil. The machine wouldn't fire in this condition due to the timing now being off as they are set up from factory to not be switched around. Was worth a try I thought.
I then did a compression test to see if there was something fundamentally wrong with one of the cylinders. Surprisingly, the MAG side checked out as about 172psi and the PTO side was 150psi. So I now feel like I have another issue to deal with once I get the MAG side firing again!
Has anyone else had a similar condition happen? I've done some research and it sounds like an almost exact situation where it turned out to be a bad coil. I currently have new spark plug wires/caps on order and a new coil to try sometime next week. Any advice/suggestions are welcome! Trying to get this fixed to I can park it and focus on getting the sled back together lol.
Cheers,
Jorg