I was dooing a little maintenance on my 09 D8 today (300 miles), popped off the airbox to clean t-bodies and reeds and noticed this...
How's the oil level you ask?
So...this leads me to first check the vent in the cap. This is where things get very interesting: The cap's vent has a check valve in it that is designed to close off when the attitude of the sled and its oil tank changes from a relative parallel state. The reason for this is so the vent doesn't leak oil when the sled rolls. Observe the angle at which the cap is to the ground.
The problem with this vent is that (at least mine) is when I tilt the cap 20 degrees or more, the vent plugs off. If you look at the caps angle when screwed on the oil tank, the angle vertical plane (ground) is roughly 20 degrees.
As my sled sits in my garage, with the cap screwed on the tank, I cannot suck air through the vent with my vaccum tester. So I take the cap off, rattle/shake the oil caps vent check valve a little, reinstalll the cap and now I get a vacuum.
So I repeat this a few times. It's about 50/50 whether the check valve opens to allow tank venting. So I lift the front end up a little to make the cap more parallel with the ground and things get a little better. But this doesn't fix the problem.
There is NO way that this check valve in the vent on my cap will work. The window of opening of the check valve is so small relative to the attitude (angle to the horizontal plane basically the ground) that there is no way that the oil tank will be vented in all conditions. Heck, it's not even venting siiting on the ground in my garage without shaking the cap half the time.
So I have 2 problems here, an oil filter that is plugged or defective at 300 miles and an oil cap that doesn't function correctly. While the cap is defective, is it the cause of the air in my line? Is this just a case of a bad cap/vent, or is this happening to other RAW's.
Sled has been sitting in the garage for a couple weeks since it's last ride. This isn't very easy to see without the airbox removal. I would rec all CFI's check this
How's the oil level you ask?
So...this leads me to first check the vent in the cap. This is where things get very interesting: The cap's vent has a check valve in it that is designed to close off when the attitude of the sled and its oil tank changes from a relative parallel state. The reason for this is so the vent doesn't leak oil when the sled rolls. Observe the angle at which the cap is to the ground.
The problem with this vent is that (at least mine) is when I tilt the cap 20 degrees or more, the vent plugs off. If you look at the caps angle when screwed on the oil tank, the angle vertical plane (ground) is roughly 20 degrees.
As my sled sits in my garage, with the cap screwed on the tank, I cannot suck air through the vent with my vaccum tester. So I take the cap off, rattle/shake the oil caps vent check valve a little, reinstalll the cap and now I get a vacuum.
So I repeat this a few times. It's about 50/50 whether the check valve opens to allow tank venting. So I lift the front end up a little to make the cap more parallel with the ground and things get a little better. But this doesn't fix the problem.
There is NO way that this check valve in the vent on my cap will work. The window of opening of the check valve is so small relative to the attitude (angle to the horizontal plane basically the ground) that there is no way that the oil tank will be vented in all conditions. Heck, it's not even venting siiting on the ground in my garage without shaking the cap half the time.
So I have 2 problems here, an oil filter that is plugged or defective at 300 miles and an oil cap that doesn't function correctly. While the cap is defective, is it the cause of the air in my line? Is this just a case of a bad cap/vent, or is this happening to other RAW's.
Sled has been sitting in the garage for a couple weeks since it's last ride. This isn't very easy to see without the airbox removal. I would rec all CFI's check this
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