As mentioned, I checked the thermostat and the fans are kicking on so I would assume the thermoswitch is ok. The temp gauge is also responsive showing each of the different bars as it heats up. While I had the tank off I adjusted the valves and also started it to make sure the water pump was pushing water, which it was. Put everything back together and although the overfill tank was full I topped off the radiator which to my surprise needed 3-4 cups, a ton in my opinion. Drove it around a little and while it wasn't getting nearly as hot, it did get hotter than it should (4-5 bars).

My next step is replacing the seal since that's leaking the coolant out but I'm not very confident that will solve my problem.

First question I have, can you do that with taking off only the water pump cover or do you need to pull the whole side of the crank case off? I'm seeing the later in the service manual so I would assume you need to drain the oil first. I just switched the oil and coolant, would rather not remove the side of the crank especially since that's not getting water in the oil. If I have to I will but if I can solve the leak with just pulling the water pump cover that would be ideal.

Next question, it's contradicting what I said I wanted to do in the last question but when doing the water pump, do you guys normally just replace everything (shaft, impeller, all seals, bearing, ect) or do you inspect what's good. With reading the shaft isn't always true and porous sounds like for the $40 it's worth doing it all.

Last question, if the machine has coolant, thermostat is opening, fans are kicking on, impeller is cycling coolant through, the only thing that could be overheating it is the radiator being plugged or fins smashed right? I cleaned the radiator good, coolant flows through and no fins are smashed but I guess I could pull it and see if needed.

Well the pump pulls from the radiator and pushes through the engine, out the top through the thermostat to the top of the radiator then it flows down to the bottom and back to the pump...so the lower hose should be much cooler then the top. If not, then the radiator isn't radiating the heat. That come from either no air flow through the cores, plugged cores, bad fan..or the flow is so fast it doesn't have time to shed heat as in the thermostat is stuck wide open or has been removed.

Good to know the direction of flow because I thought it was the opposite. I wish I checked the top hose but I already ripped it apart. I pulled the thermostat to replace, I will test it if I have a chance. Update, just texted the thermostat in a pot of boiling water. At ~150 degrees it's open about 4.5mm which is to spec. I guess I'll see when I rip into the impeller.

Ok. I ran it before reading your reply. In the 5 minute ride it was at one bar for most of the time but did got up to two, and then climbed slowly. The fans were also on so that leads me to believe the thermo switch is ok. I did feel the radiator and it was warm, the top of the radiator especially I would say was hot, you couldn't put your hand on for any amount of time. The radiator hose to the water pump was extremely hot. Between the radiator and hose being hot, that's indicating the coolant is flowing no? This is making me scratch my head.

I had this quad for about 3 years and never had an issue. Out of nowhere the quad started to get hot after hours of driving. I noticed the fuel injector red light was on then she temp light started blinking so I shut it off and tried to let it cool some. I limped it back to camp, hosed off the radiator and it seemed fine. Rode for a few more hours and all was well.

When I got home, I cleaned out the radiator really good making sure I got the backside which was caked up pretty good. Hoping that took care of it and short trips it was fine so took it on another trip. Same thing to where I rode for a few hours without issue then it overheated and injector light. Again, limped it back, sprayed it off and rode a decent amount more. I noticed it had a very slow drip from the overflow hose but almost what I saw others say as normal.

I bought it used and pretty sure it had the factory coolant so I switched the coolant out to rule that out as well as seeing it helped with others weeping out the overflow. It's still overheating unfortunately and the overflow is now dripping steadily. I didn't find the bleed screw but ran it a lot with the cap off and even put it at a real steep angle with the front up with the cap off as I read helps.

Looking for advice. My next plan was to replace the waterpump and seals. I don't think the coolant/oil seal is bad since I don't see any coolant in the oil so I was going to try to avoid it but while I'm in there I probably should just do it huh? I'm also reading about the thermos switch. I do feel like the fans may not have been on but they do come on when shutting it off. Honestly haven't paid that close of attention.

Yeah, I hear you there. You don't happen to know if the service manual has the test procedures for the electrical components (switches, speed sensor, actuator, relay/diodes, ect) do you?

I just went through this all on a different machine and the manual was very useful. I need to find one for this model and check it out.

I'm helping a friend with his quad. The 4x4 stopped working and after some testing we found that it works when you push down very firmly on the relay. We cleaned all off the connectors and removed that "plug" from the relay box to make sure all the wires were seated correctly.

Some things are strange:
1) If you push on the relay to the left of the 4x4 the quad will start cranking to turn over the engine
2) If you hold down on the 4x4 relay, it will not go in 2x4. You need to stop pushing on the relay.

With the other relay cranking, I'm starting to think it's a different electrical issues such as the switch but the switch appears to be working fine if it wasn't for this issue, meaning when you switch between each mode it will not hesitate as long as you are pushing on the relay or what not.

Does anyone have experience with theirs acting the same?

Does anyone have a spare sitting around? Primary Spring 0951-1016 Gold/Yellow/Pink

Following up for those who may need it. This left off as getting the machine up to 40 mph but after taking it to the trail ones the speed was severely limited again. I had some help today and identified that the primary ramp plate or clutch variator is supposed to have a hex stamped in it to marry with the hex on the clutch shaft and it was rounded out causing the slipping.

The ramp plate I have is no longer available and was superseded with a new part which is more stout. Unfortunately the design uses a different size hex so it doesn't fit on the rest of the clutch. It sounds like these are problematic and I was told not to get a cheap replacement for safety concerns. As much as I would like to get a new design clutch I'm going to sell the machine and don't want to shell out that kind of money for it.

Now I need to find out where I can find the OE ramp plate or at least somewhere that meets OEM spec. If anyone reading this has a primary that they are not using please get ahold of me.
Old Part #:  0GR0-051002    New Part #: 0GR0-051002-000001

3-4psi under is actually quite a bit. Is it enough to drop the top speed that much...I don't know..for sure it will some. I would do a full inspection and cleaning of both clutches and belt as well as air intake and filter. Anyone do a compression test on this lately? Any possibility that its in need of rebuilt? If you have been running the paper CFM filter on it in dusty conditions...the answer may likely be..yes. People are only getting on average 1200 miles before the top end is gone.

I'll have to look at the gauge I used when I get home, it may have been within spec but I'll check. It doesn't have a paper filter and only has about 200 miles and 75 hours on it. I just cleaned the filters before I rode last and unfortunately I didn't put oil on the outer one and it was extremely dusty out last time riding which I wasn't happy about once I realized. We didn't ride long or hard though and when I cleaned it after it didn't look like anything got through.

I will run a compression test later as well but doubt the issue is with the engine (doesn't hesitate, revs up to rpm just fine, and most importantly wasn't having the issue before getting stuck in mud.) I can't remember the exact details since this was quite some time ago but I wouldn't doubt that I glazed the belt or something tweaked in the clutches. I'll pull them apart and check them out. While in there I saw posts of other people putting on different weights and springs from can am (part # 0901-7103 and 0951-1016) smooth the take off out some. Do you have any experience with those particular ones?

I looked in my manual on my 2015 800 which should be pretty close on fuel specs..maybe a hair higher but in electrical it has the specs in MPa for pressure and Liters per hour for flow rate so: The pressure at .33 MPa, +-.01Mpa is 47.86psi +- 1.4psi Anything outside that range replace the pump. For flow rate its 35 liters per hour which is 1,183.45 Oz per hours or 19.73 per minute..or .33OZ per second...so get a measuring cup that can measure down to one OZ and in 5 seconds it should pump 1.63 OZs. Look in your electrical section for yours.

I pulled the fuel filter and cleaned it with no change. I measured the fuel and it was around 44 psi which is pretty darn close to the specs combine with the flow was if anything a little higher than the numbers listed above (15 seconds gave me roughly 6 oz of gas). The machine was only going 26 mph but what was getting me is the rpm wasn't going above 5,500. Even if the belt was slipping I would expect to see it go into the 7k. I rev'd it while not in gear and it did go up to the 7,200 range which has me believing its not a engine or fuel issue but more a transmission/clutch/differential/brake issue. The brakes have squeaked very bad since I got it but when in the air they don't have a lot of resistance.

Any idea what my next step should be? I'm leaning towards jacking it up and quickly checking if I feel the brakes grabbing again which I doubt I will. From there pull the clutch to see if there's something going on with the secondary and replace the belt while I'm at it.

I looked in my manual on my 2015 800 which should be pretty close on fuel specs..maybe a hair higher but in electrical it has the specs in MPa for pressure and Liters per hour for flow rate so: The pressure at .33 MPa, +-.01Mpa is 47.86psi +- 1.4psi Anything outside that range replace the pump. For flow rate its 35 liters per hour which is 1,183.45 Oz per hours or 19.73 per minute..or .33OZ per second...so get a measuring cup that can measure down to one OZ and in 5 seconds it should pump 1.63 OZs. Look in your electrical section for yours.

Thanks! I'll check mine out and convert it over if different. For the belt spec I called and it's 33.5mm I believe new is 36mm. Mine is as 35.7mm so plenty of life left. It started at 40 mph and went down to 26 mph and was a super dusty day. Starting to wonder if the air filter may have contributed. I'll check that as well as the fuel pressure. After that it may be left to pulling the clutch to see the backside.

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I'm wondering if a worn belt would cause the speed to be limited.

In a nutshell...yes it can. The belt's specs should be in the service manual. While there do a full service, cleaning and inspection of both clutches.If all is well look to things like fuel pressure and volume. Filters can and do get plugged quickly sometimes which also limits speeds.

Unfortunately the manual doesn't have the spec for the belt. From what I gather they are 35mm new and should be replaced at 33.5mm but I will call the dealer to see if they can confirm. I checked and cleaned the air filter but will look at the fuel filter. You don't know what the volume should be offhand do you? Or the best way to measure it besides filling up a jar and timing it?

I haven't experienced it on my 800XC, but I do know that on my previous Polaris 450, when the belt started to wear the top end speed would be reduced.  On my Kawasaki 650, as the belt wore I didn't notice any change in top end speed, but it would "walk" when in gear without throttle input.  Those were my clues on the previous ATV's that the belt was needing replaced.

Thanks for the info! I really would like to find out what the top speed is for these new to have something to compare it to. I looked at a ton of videos and post but the only one I found was a guy going 60 but that wasn't for the HO and I would also assumed it had some tuning and/or a clutch done on it.

If anyone knows how fast their stock 500 HO went please let me know!

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I'm wondering if a worn belt would cause the speed to be limited.

In a nutshell...yes it can. The belt's specs should be in the service manual. While there do a full service, cleaning and inspection of both clutches.If all is well look to things like fuel pressure and volume. Filters can and do get plugged quickly sometimes which also limits speeds.

You don't know what the stock mph is for the 500 ho do you? I just checked/cleaned the filter. I have a new belt to compare, I thought it was oem but appears to be a knockoff so if I need one I'll probably just order a new one. Will look at the other things you mentioned if the belts not worn.

One of the most common issues is that the plastic gear that moves the fork tends to strip and on some it's been known to go into 4wd but not cone back out. On others it jumps a tooth and is off-alignment. When assembling it is important for it to be in 2wd and the slide be to the far right as you look at it when putting the actuator back on. Just some info-dump.

I feel like I'm almost there. My actuator came in so I got that replaced along with the gear sensor. Now all gears switch on the dash and the 4x4 works as it should. Good news!

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I'm wondering if a worn belt would cause the speed to be limited.