I was changing oil on my 2003 500 scrambler. I got to the step of pinching the hose at the top of the oil sump so as to prime the oil pump I'm told. This is my first time performing this task. When I attempted to pinch the hose about 2 to 3 inches away from the top of the oil sump, I felt a slit in the hose. I disconnected the hose to get a good look at it. The 1.5 inch slit I found had a white line circling the cut. So to me it looks as if it was made that way. I'm curious as to why the slit is there. It appeares that the hose goes from the top of the oil sump and routes over to the air box. What is its function? If I ever get stuck in high water I'm wondering if water could enter through the slit in the hose and go directly into the oil sump? If any of you 500 owners have noticed this and know the reasoning behind it please inform me, Thanks....

 

My SP 400 & SP 500 HO carb have the same thing. It is supposed to be there. If I remember right it serves as a vent so you don't build up pressure in the oil system. I don't worry too much about getting water in there since I don't go in REALLY deep water. hope this helps ya!

 

Ya its a good way to get water in your engine, the older ones had an aluminum oil tank, they changed them to plastic because the aluminum ones where causing to much condensation, I think its cause water is getting in through the slit.

 

More like a plastic jug is cheaper to make than the old Aluminum alloy ones. Lots of dry sump motors out there such a Harley,s Davidson bike but most all external oil tanks are not plastic.

 

Yes it is on the 2006 Sportsman 450's also....If you got the Polaris oil change kit...In there will tell you The following:

This is the vent's line pressure relief slit!!!!! Hope that helps.........That's why you need to clamp or pinch the vent line about 2" from the tank....so you don't clamp the oil tank fitting if your too close....Caper..

 

That might be one of the reason NOT to go above the floorboards.....YA RIGHT!!!!!!!...Caper....

 

The slit is there in case the lines freeze going to the air box. If your in an area where it won't freeze you could probably replace the hose without a slit to prevent water from getting in. Someone correct me if I'm wrong

 

The only way that line would freeze is to have your air box FULL of water.............Caper.......

 

Or condensation. Remember Caper, not everywhere gets cold and stays cold like here in the winter. Some places actually warm above freezing during the day in the winter LOL. And my bike stays in the shop in the winter so it's outside when riding and staying warm at night. And I have noticed some condensation in the ol' Scrammy but not the new one yet.