well after our memorial trip... my sp 500 was sounding pretty rough.. like a knocking... sound.. so we went wednesday and did some mudding.. and after we were threw.. it was kinda soundin worse... so we checked the compression and only 70 pounds.. we were gonna do the top end ourselves but this mechenic told me for 400$ he could do it rite.. so now my wheeler is in the shop for a couple weeks...

does anyone know or can explain how mudding is hard on a machine.. i mean i dont hold it wide open...i dont floor it into the holes... i mean is mudding any harder than riding the trail?

 

mudding is way harder on an atv than trail riding.....................

 

yea i hear that alot but nobody knows why... thats why i asked the question.. if you think its WAY harder... why do you assume? explain.. i want to know....


i think that the way i mud isnt any harder than riding on the trails... and i go threw alot of mud... i dont think for one second im replacing my piston because of it either.. its been making the knocking sound for a while and i figured before i caused more damage i better get it fixed... soo... people that have a explaination... lets hear it

 

Mud has a higher rolling resistance than hard packed dirt and air. It takes more horsepower to move through mud than riding down the trail. The engine is generating lots of heat, the only way to shed heat is via water, airflow, and oil.

When mudding the ratio of heat to airflow is off the scale, leaving only the oil and water to pick up the slack, however, water is cooled by airflow; which leaves oil to do the bulk of cooling / lubing. The high heat can 'cook' the oil, making it useless. Which can lead to engine parts wear / failure.

I will go so far as to say your parts failure comes from oil failure more than any other reason. Were I you, I'd switch to a cheaper type oil and change it everytime I go tearing through the mud, keeping the oil fresh so its cooling / lubing properties are at 100%.

Now, don't confuse what I just said. Always run oil that meets manufacturer spec. But maybe instead of synthetic, switch to conventional oil and change it more often.
If you insist on the best, switch to racing grade oil. But again monitor its condition.

Oil that is black is burnt up. Change it. Now. Oil that is brown has some life left. Oil that is clear is still fresh.

My .02

 

wow.. that was awsome.. and really makes alotta sense... what kind of conventional oil could you use in my sp 500... i do know that the polaris guy ( of course ) said that the 99 sp 500 needed thing oil to make it up to the cam at the top of the motor.. i heard that cams went out on alot of them machines because the oil wasnt making it up there...

and also would i have to drain everything.. or could i leave that little bit in the crank, and just put the 2 quarts in my oil resvior.

1) what kind of oil would still make it to the cam. ? besides the polaris oil )
2) would i have to completly drain all oil. or just the oil resvior?

 

It all comes down to specs. What are the oil specificatons listed by Polaris for your machine?. You need to match the API specs and find out whether you need synthetic or not, and whether you need 'non detergent' oil. Conventional 'car oil' has detergents in it to help clean sludge out, and friction modifiers to make it more 'slippery'. It is not recommended for machines that use engine oil to cool the clutch, because to do so can cause the clutch to slip.

I believe Popo's have the engine and tranny separate, check you manual or mechanic for your machine to verify. If they are separate, you should be able to run 'dino' oil in the engine as long as it meets Polaris' specs, since you are changing it more often than the people who wrote the manual are expecting you to.

As for whether to do a complete oil change or just the reservoir, you'll have to make that decision yourself. It all depends on the condition of the oil in the crankcase. Just make sure to think of the oil filter too, and change it as needed, not just based on mileage.

Here is a link to a manual if you need one.

Shop Service Manuals - A.T.V.

 

I hope everyone reads Heftys' post above... it sums normal ATV use and "misuse" up perfectly... Oil is not only meant to lubricate but it also cleans and helps to cool... Extreme heat is devastating for a 4 stroke engine... great post Hefty... tj

 

Polaris oil pumps have high tolerances,so they need a thin cold start oil like 0w-40 or Polaris new 2w-50. to get oil following quick on cold starts.

EX 0w-40

The first numbers in oil 0W ,the lower the number the thinner the oil on cold start ups. The last number 40 mean its operating thinkness upon warm up and operation.

Sythetic flows better then conventional even if the Numbers are the same.

In a polaris try and use synthetic 0W-40 or Polaris's new odd ball 2w-50.

My Clymer manual for a SP500 says 10W-40, with advice like that you will need a new cam lobe earlier then need be.

 

Also your RAD when mudding is never 100% clean so the cooling effects on the engine may never reach that temp. if the fan running with plugged cooling fins on the RAD...............Caper,..

 

If the motor was running hot the thermal sensor at the motor would cause the over heat light to come on. The sensor at the rad just tell the fan when to come off or on.if that fails you still get the motors's heat senor to warn you on you display.