Well, got a new gasket. What a stupid design, the gasket is razor thing where it goes around the lower bolt (where it is currently dripping). Plus, the new gasket is metal, whereas the older one was paper. Scraped off the old paper one (on both sides). The impeller looked fine, and was def bolted securely (not stripped or free-spinning).

Tightened the housing back up and .... still dripping at the lower hole.

The gasket was concave, so I didn't know whether to put the raised side of the gasket towards the engine or towards the outside. Also not sure if, since it was metal, do you use silicone or something else?

Google "Sportsman 400 gasket water pump" to see how little "meat" there is where it goes around the lower bolt.

Added new radiator cap. No change. I idled her hard, put the cap on, and drove her hard around the yard. When I stopped and shut the key off, I head this weird "rushing noise" and watched as the coolant recovery jug went from nothing to full....

Very strange behavior. The shop offered to diagnose the trouble for a couple hours of labor, I am probably going to take them up on it.

 

I always used a little Threebond 1104 (same as Yamabond) around the gasket to hold it in place and a dab smeared around the cover after cleaning the case and cover thoroughly. Think it might be worth the effort to let another pair of eyes look at it. Plus when you say lower hole are you talking about the lower cover bolt hole or the drip hole under the housing? If it's the drip hole the water pump seal is out.

 

Yes I am back...I think like most of us, I hate to give up.

Got some Yamabond for the gasket and while I was at it, I pulled the thermostat. I boiled up some water on the stove and took some tongs and dipped the thermostat. No change. Didn't move...so bad thermostat. I hear they are plenty pricey.

If it *IS* the thermostat, would that affect my temp sensor? Or is it not getting any hot water because the tstat is staying closed?

Thanks for listening!

 

If anything the radiator sensor would get hot quicker with what water was in there and trigger the fan.. On the down sides to this IF the thermostat is the problem and just allows a small amount through,the radiator sensor can short out also if not enough water reaches it. Sort of what the old sensors did that were located at the top of the radiators. They could over heat and short out if they weren't in coolant at all times. If you're sure on the thermostat you can get them cheap at amazon or here.Thermostat for Polaris Sportsman 500 1996 1997 1998 1999 2000 2001 2002 2003 04 | eBay In 23 years I think I replaced 3 total. One was because the pin cocked sideways and blocked it from opening fully..Usually something that lasts on the old 500 or the 400 for that matter.

 

Hey OPT, any thoughts on Caltric parts? I read a few reviews and some people love them, and others say they are total garbage. They have all sorts of Polaris compatible parts for far less than name brand.

So I should wait for the thermostat? Would I gain anything by running it (just idling) without the tstat? That way water would def get to the radiator and I would be able to test that thermal sensor. Just wondering....

 

I'd get the new thermostat. Test it in hot water before you install it also. As far as this mechanical part Caltric should be as good as any other. On electrical parts Caltric like you said has had mixed reviews. On youth model Polaris stators some have posted that they had problems with them,but at the prices they charge sometimes hard to resist.I've had some oem Polaris electrical parts doa also if that makes you feel any better.

 

Ok so if you're still readin along, THANK YOU,

Got the thermostat, applied some of that blue RTV sealant to the gasket on the water pump. Tested the thermo, worked perfectly. Installed it.
Have a drip from the bottom of the water pump, looks like a weep hole or something.
But ran it with the cap off, and for once, it looked normal. I could see the fluid flow along. As it got hot, the fluid rose and rose, and when I switched on the fan, the fluid dropped back to normal. So I almost there....I need to fix that weep hole leak, and I need to figure out why in the hell that thermo sensor isn't doing its job. Even with the he radiator scalding hot, I tested the leads and nothing...so I hard wired it to a switch for now.

 

Sounds like a bum sensor if you have to wire the fan direct. Resistance test on the sensor is one way to see if it's working or not,but this may not always be accurate. The sensor may be set to bridge the internal switch at a higher temp than the oem switch or it's just plain faulty.On ebay they've sold quite a few and most people don't have any problems with them. If the coolant is leaking from the weep hole the water pump seal has failed. I know there are videos, people that have posted pics on using pliers and dry wall screws on this seal but you're taking a chance on bending this thin shaft. If you do the engine has to be split to replace it.. Not worth the chance. The correct tool for this is expensive for a one time use.On this I'd let a dealer pull it and replace the seal,usually for an hr labor if you have it torn down ready for them to get at it.

 

I wired fan direct on my CanAm DS250 after removing, cleaning and refilling radiator. Overheating light took longer to come on but still did after 15 minutes of riding. What do you think my next step should be? Water pump, bad cylinder sensor? Thanks

 

You can probably get better results in the Can Am section,but try leaving the radiator cap off,lift the front end with front tires off the ground. Let it idle for a few minutes to remove any trapped air pockets. If both in and out radiator hoses are firm and warm to the touch,the coolant should be flowing through the engine and radiator ok. You can look into the radiator to see if coolant is circulating. Might be a good idea to have the fan running off the correct sensor as all you're doing is wearing out the fan motor. Sensors can be checked by checking resistance when cold and then after dropping in hot water. Resistance should drop. If resistance stays the same cold or hot,the sensor is faulty. Here's some cheap Can am service manuals that might help if they include you year model.http://can-am-atv.brssm.com/