2000 Polaris Magnum 500 project

[BrianF]

my wife picked up a little project for the acreage today. Higher mileage unit with winch and stout snow blade. So I got a few questions.

I am not worried about using Polaris spec fluids, other than a litre of chain case oil and a small bottle for the hubs that came with it (nearest dealer is at least an hour drive) I plan on using atf for the hubs and chain case but am confused on both differentials.

Found an online manual that covers a wide arrange of polaris atv's, it specs gl5 90 weight gear oil front and back. But all the online reading, people say to use Atf up front or angle drive fluid.

I will take a sniff tomorrow and maybe answer my own question but wondering what others are using.

I read that somewhere along the 2003/4 model year, polaris changed the 4x4/awd system to the Hilliard front diff, necessitating the angle gear lube/atf over gear oil. Again, I cannot find much definitive info, shy of calling a dealer to run the vin.

The tires are good but has one slow leak. The carb has a leak from the bowl, making it difficult to start after sitting a few days. Not a big problem. I read it has a mikuni 34mm slide carb, i will tear it down to do a clean as well as it likes a bit of enricher to run top.

Pictures to follow but any advice or tips is welcomed. TIA.

 

[BrianF]

Edit, it looks like a bottle of demand drive, which should be good for the front diff, regardless.

 

[BrianF]

So some updates.

I accidentally ran the carb dry one day and when I opened the petcock it absolutely flooded the carb and engine. She poured the fuel out.

Teardown showed the needle valve was badly worn. The guides worn down and the tip rounding. I could not get it to reliably seal when testing. Ok thats fine. Ordered up a Wolftech kit, which too forever to ship.....

The carb was torn down and tossed in an ultrasonic cleaner i stole from work. I will buy one in the near future. The carb came out spotless in under an hour. I blew out the passages with air and clearly the low speed discharge holes were now clean.

The main and pilot jets were in great shape so I reused them but I did use the new air screw, even though the oem was in great shape. 2 1/4 turns out with the new one, which was what the oem one was. The alignment marks even lined up.

The new needle valve and seat made a world of difference. Sealed like a charm when tested.

Popped it in today and learned a few things. Turns out I caused some adjustment issues with the enricher and throttle cables. I had to prime it to fire and she took off to at least 3k rpm. After testing for air leaks, idle screw, air screw etc i found the throttle cable was taught. After winding it down, she idles great now and once up to temp I set the enricher, which appears to work. Time will tell once the temperature really drops this winter.

After somw test driving, I did the front hub fluid. Found both low and one almost empty with rust colored oil. No noticeable leaks on the seals... i used the same Federated Co-op ATF SL, group 4 multi vehicle fluid in them. Got her ready to go now.

I forgot to mention, several weeks ago I swapped out rear diff, transmision, engine oil and so on. 75w90 in the diff, ATF SL in the transmission, a mix of PYB 5w30 and Motomaster (Shell made) 5w50 along with a Fram Ultra in the engine. I greased her all up but accessing the front diff will wait. Its a tight fit. I also swapped out the coolant for some fresh green mix.

She runs great and has some juice now when you punch it. Quite happy!!

 

[CDX825]

Your front diff will take gear oil. Around 2004 they switched over to the hilliard front diff that uses Demand Drive Fluid.

 

[BrianF]

Thanks you! Yes, the dront diff is all that is left to do. I just need to get some more small diameter tubing to fill with. If I recall it only needs like 5 ounces.

This morning it was a few degrees below zero and she fired up first crank. It plowed the sticky, wet snow like a boss. Ran flawlessly. Now my plowing technique is lacking so I guess I should head back out and practice.

In reference to the great white trash show, Trailer Park Boys, I named her the Green Bastard, from parts unknown.

 

[CDX825]

That's funny! I like the trailer park boys.

 

[BrianF]

Did some maintenance on the Green b-tard, parts unknown. Since the hub oil was little to non existant last time, as well it was garbage looking, I did them again today.

The ATF came out looking nasty again but there have been no issues with some hard winter use. The AWD engaged everytime.
I used my usual 7.7cst group 4 ATF. fill the hub and then clock it to 4pm to drain the excess. Very easy, thank you for that Polaris!!

The front diff had not been done by me yet. When was it last done? The previous owner could not remember but since there was no weeping or leaks, I had risked it out.

I had to push the lower rad hose over and disconnect the inner tie rod ends to access the little fill plug. The manual i had read states 5oz of gear oil and that there is no easy way to check the level so just do a drain and fill. About 5oz of clean looking gear oil came out and I managed 5oz of 75w90 group 3 GL5 back in. Only a minor spill. That diff has got to be one of the worst fill locations known to man. Next time I will drain the rad and relocate the lower hose completely out of the way.
Next chance I get, the transmission will get a drain/fill With the same ATF. Its level was perfect still. I am also going to source rear axle seals for another project.

 

[BrianF]

Furthermore, I did the transmission and spark plug today.

The ATF i added last fall came out quite dirty looking. Usual garbage on the magnetic drain plug. Super easy to drain fill and monitor level. One manual called for 17.5oz but it was closer to to 20 to get it to level.

The plug was easier than I thought, once I figured out the combination of short extension and u joint. Out came the NGK BKR5E, which was well used. The small shop i was at was low on stock and only had the B&S cross. The book calls for .028" gap, which it was nearly bang on. The old plug was closer to .060.

On test drive she fired up instantly, had plenty of snot and no backfires on fast and long deceleration. Ran good.

Up next I am looking to order new axle seals and A arm bushings.

 

[BrianF]

Holy smokes boys, this thing is the gift that keeps on giving. Ran great for most of the winter, then in the real cold, plowing snow, she would lose power, die and have a hard restart. Traced it to a broken vent line. It ran from the tank to the headlight pod but had broken at the steering shaft and would ice up. Easy, just pop the cap a bit.

Then shortly after I was getting mid to high end bogging. Wouldn't stall but no power and hard to pin down. I ended up popping the air box lid and giving it a new Napa oiled foam filter. This all but fixed the problem. But it would run a bit garbagey from time to time. I new the carb was clean from last time and she had a new fuel filter it seemed like a rich bog as giving it more air helped. I also checked clutch operation and both were doing what they were supposed to.

I ran it like that until the other day, when she powered down and died on my wife. It was also leaking gas from the overflow. Well I guess this is worth my time to rip the carb out, which is somewhat involved in the Magnum.

What did I find? Well something was rattling loose in the bowl and to my surprise the main jet wiggled free and then jammed the float. To make things better, it sat and vibrated against the emulsion tube, ruining its threads.

I stopped in at the local sled and atv shop and they got me a new jet, a bit richer, 152.5 to 155 but it should work decently. On assembly I found the threads of the emulsion tube were also damaged, albeit not as bad. Not having all my tools present, I filed down an awl and used it to clean the threads and eventually get the jet seated.

I have it reassembled to a point where I can try and start it to set the idle. But as it did the last time I had the carb out, it is very hard to get started and stay running. So tomorrow I hope to have it good.

 

[BrianF]

So she lives. I figured out my starting issue. You have to have the idle screw on the carb turned out to a point where the engine turns over quick. Then you have to adjust your throttle cable slack to where it will fire and idle.

So when I had the carb out last, I had made an error in assembling the throttle cable onto the carb, it did not seat properly and I had to adjust out my cable just to get it to run. Now this go around I installed the cable correctly, which threw my cable tension way out of whack. Now its balanced, starts well and performs like she should.

While a 155 is a touch fatter than stock, it ran perfectly with a freshly oiled filter and with the airbox lid installed. Visually I had compared both jets side by side in the light and there was no discernable difference.... well the Green Bastard, parts unknown is back at her.