Not sure what happened with the previous post, so we will try this again...

I have an engine noise that has developed and gotten worse since I have owned the ATV. It is a 2001 Polaris 500 Sportsman 4x4. I have had to do a lot of up keep on it. From replacing axles, fixing reverse indicator switch, bleeding the cooling system of air, rebuilt the carburetor, and replaced the starter. There is much more I have done, but this is the bases of it.

The ATV sat for awhile waiting for me to install the starter, when I finally did I did not remember the noise from the ATV previously. I am not sure if it is in the top end as in it needs the valves adjusted or if it has something to do with the Bendix/starting assembly or the recoil starter. I would like to isolate the problem before I put anymore time into it trying to diagnose the problem. Below is a video of the noise. I did not replace the Bendix when I replaced the starter, which tends to draw me to that conclusion. I still need to dial the carb in as far as tuning goes but it runs like a scalded dog otherwise. The noise just gets worse with more RPM's.

Any help or assistance you can give on where to start would be greatly appreciated! Thanks.



Running previously, only thing changed is the starter between videos.

 

Check the drive clutch. See if you have slack when you grab the clutch and twist it back and forth. Sounds like spider button are worn causing the clacking noise. You can even pull the clutch and see if that's the problem.

 

Thanks. Sorry about all the video's. Post definitely went hay-wire....


I will give that a shot. I had to fix the recoil start system and while I was at it pulled the bendix (and also found one of the bendix starter bushings shot...) and it still made the noise. I will pull the clutch either today or the next day I am off it see if that isolates the issue.

 

Pulled the clutch. Sounds as thou it is coming from the top end....

 

STOP!! Time to pull the valve cover,check the valve train out,but sounds like it's piston or rod slap..

 

Thank you, I will and take a peak.

If it is the latter, would that be something a mechanically inclined person can do in the back yard?

 

Not really.. This is where a good service manual come into play.http://visit.tradebit.com/visit.php/...75/264163430/9

 

I have yet to pull the valve cover, however it appears we will be taking a replacement motor route. Weighing the options with going used or rebuilt with a warranty. Leaning toward the rebuilt side of things. Then it will just be a swap on my end. Should know something in the next few days hopefully.


Are they any real specialty tools that are a must have when doing an engine swap on this thing? I already have a cvt clutch puller, but don't know of anything thing else really.

 

No specialty tools needed on just an engine swap other than a flywheel puller. A good 3 way type puller will work or most auto store will rent a harmonic balancer puller. Try to align the stator plate in the same place on the replacement engine as in the old one.Just look at the marks. Compressor and air tools will help and saves time and your knuckles.

 

Thanks! I appreciate the help. Is there a listed break in procedure for a newly rebuilt motor? Maybe something Polaris recommends? I have the service manual for 1996-2003 500 Sportsmans, but it only states staying in a 1/3 throttle range for the first 5-10 hours and then progressive increase after that. Doesn't state anything about oil changes or what not. I would like to get the longest life out of this rig if possible and I know breaking it in correctly is much needed for that.