Quantcast
Jump to content

98 Polaris having compression problems


MARIO560377

Recommended Posts

I have the same problem with a dirtbike I bought. High compression is from carbon build up on the piston and in the combustion chamber, check there. Polaris 4 strokes have a automatic decompressor that opens an exhaust valve slightly when cranking with the starter to ease starting but will affect your compression readings with engine cranking speed. Test your compression with a good tester that threads into the plug hole, not the ones you push and hold by hand, and see exactly what your reading is. If you get inconsistent readings, do a cylinder leakage test instead to see if it is your valves or head gasket just make sure your ignition is disconnected or kill switch activated while testing. If all checks out good there, it could be damaged decompressor or exhaust cam lobes...I don't have a 4 stroke but this is what I did on my 2 stroke and I ended up replacing the piston and rings and decarbonizing the chamber....:wink:Good luck!

Link to comment
Share on other sites

  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Forum Topics

    • By killerklown
      I received an additional parts engine with a 220 Bayou I purchased, but I believe it's a couple years newer than the ATV, Is there a way to decode the engine serial number like we can with VIN numbers?
    • By alexwv1863
      I'm looking for a repair manual that's specifically for a 2016 Arctic Cat 500. I have looked in the downloads section and there's one but it's for 500,700 & 1000 models. When looking through it, things I'm trying to find to fix on my 500 is not specific for just that model, and it's geared more towards the 700 model. So, needless to say, it really isn't helping me. I really hope someone out there has one. Thanks.
    • By hporter1208
      Okay, so I have a 2002 Rubicon 500…bought it last year and it sat for several months until I put a new rear axle in, FINALLY got that done and was super excited to finally have my wheeler going, just to notice a strong gas odor. Popped the seat off and sure enough, pouring gas from the carb overflow. Fast forward a few more weeks and get the new carb and get it in, no leak! Yay. Except now I have no spark. 😒 I’ve tried another plug and checked and am getting no power to the coil pack. I’ve read and read and mostly what I’ve found is ECU, which is fine…but I like to exhaust all avenues before buying the more expensive parts just because I don’t wanna spend the money and it have ended up being something simple that I overlooked because I was trying to rush. 😂 I don’t know if it’s relevant, but I read on another post that someone had similar issues with theirs and it was the sensor on the side of the carb, just a thought since this literally happened after I put the new carb on. It also displays “- -“ on the display screen where it should show the gear position.
    • By HondaRubi2022
      Hello,
      I have a 2022 Honda Rubicon and I have an issue where it won’t start, when I turn the key for power nothing lights up and it won’t start but the lights will turn on with the light switch, I’ve checked all fuses and they’re good, I don’t have a wiring schematic I’m not sure where to start, I checked the ignition fuse when I turn the key on and there’s no voltage there, I used a jumper wire from the batter to the top of the ignition fuse and then it works fine and starts fine but as soon as I turn the quad/key off it won’t start again until I jump the ignition fuse with battery power, just wondering if anyone could give me some tips where to go with this or if anyone has had the same issue, thank you.
    • Sell your car with CarBrain
    • By Joeguy
      So i bought a chinese carb and in messing around still trying to get it to run right i figured id pull the spark plug to see if it was running rich, well it was definitely but also i have a nasty mark on the strap (i think thats what its called) that looks like the piston has been smacking it. I never actually pulled the plug because i had it running for a second on starter fluid when i first bought it and was just stupid and figured whatever was in there was good. The part number on it is DPR7EA, which is similar to what is called out for in the manual but i assume the little bit off that the code is means it must be a bit longer or something. Unless the plugs are made like this, but i can pretty easily see that metal has been pushed away from the area of impact. What are the odds that my piston is trashed now you think? It does still run just not well due to carb issues but thats a whole other problem.

      Actually i just took a second to google both plugs and it says the reach is the same its just different resistor values and gap size, so maybe the bigger gap is why its hitting. Either way the actual one for it is on the way and i hope it just didnt do to much damage. Wish i woulda just went over the whole thing like i normally do with this stuff.
×
×
  • Create New...