I have at least two machine with slits in the clutch covers by the air ducts. I have spent tons of time searching ebay looking at clutch covers and don't see any with with these slits. why do my machines have them?

Being a very large ( ok ok heavy ) guy riding deep snow/ back country style snowmobiling, i have blown many a belt and am very familiar with what happens and i find it very hard to believe a belt could cause this thin groove in these covers. I have the exact same groove worn in two possibly THREE covers of my machines. one is a 2003 sportsman 500, one is a 99 scrambler 500 for sure and i think my 99 scrambler 400 has this groove also. my 2000 sportsman 500 that i bought new does not have this slit. I think the machines that have the slit have the 3" air outlet but I don't think that should matter.

how in the world can you go into any kind of water with a 2" slit in the top of the clutch cover? how did this slit get there? they look like they were cut with a saw.

 

i got a few better pictures. I realise I had some belt rub on the one cover but if there was piece of belt whipping around in there it would not be such a neat slit. especially in the same spot, same length in both if not all three of my covers.

 

This was a common issue on all the model covers from day one! They first started making the covers stronger after the 96 model year up until more changes mid year of the 2000 models. Even your 2003 model has an updated cover part #change from the one you have on now..Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse You can go with the updated,stronger cover for your model,shows to be $40 bucks. Problem is up until the 2008 models some could still got hot and some warped,the belt and clutch sheaths would touch the cover and make a nice clean slit. The covers were molded too close to the shape of the clutches and belt,not allowing enough air circulation for cooling.Also check motor mounts for separation and clutch backing plates for warping as this can cause problems also. You can replace these with the over size covers offered starting on the 2008 models and later if you wish,or just get the up graded ones for your models.The problem is on the bulbous covers you need to adapt the larger exhaust outlet of the cover to your existing outlet tube.I've done this by just cutting up a motorcycle tube in place of the small rubber sleeve you have now and zip tie them on.I don't know how many covers I replaced until the 2008 models came out. 2008/up covers show to be the same price as the 40 bucks for the "improved" cover for your 2003 model and others.To make things even more complicated,even these later model covers show an updated part # change for replacement covers every year until the 2011 models. Some changes were for the drain plug added..Glad I'm retired..

 

once again thank you for your wisdom. yea, the 03 cover has a drain plug but seemingly no threads. the plug just pushes in. i'll just goop some rtv on it and put a little rtv on the slit when i put it back together. i guess.

i don't expect very much from my machines, they get little use only around the house. very few miles, with no mud or water.

thanks for the tip about the tube, i have a couple old dirt bike tubes laying around, i never thought of that!