Funny but messy problem today

[Canadian Lad]

Took out the machine for the first time today. It was -28 Celcius and had a hard time starting as battery was slightly run down after a summer of storage. When it started and warmed up I looked under the engine to see oil dripping down. Checked the filter and drain plugs but they were OK. (figured I might have left something loose when I serviced it early in the summer) Opened up the air box and wow saturated with oil leaking down to the belly pan coming out of the rubber hose in the air box Shut it off and check everything I could think of and nothing. Started it up again and problem did not come back. Cleaned up what I could (in the bush) - checked the oil and down 3/4 a liter. Took it for a ride and worked great.
Any ideas on what happened or why. My thought was something was froze someplace and the warmt from the running engine thawed it out. Scared the #*$&@ out of me. I have not had the air box off the sled so the hose everyone talks about should be OK and also it did not leak later.

 

[woolyviper]

i've done that



twice.

 

[Canadian Lad]

Did you figure out why it happened

 

[7 skulls]

I had the same thing happen to my 06 nytro the first season I owned the sled. After a late night ride in very cold temps, my bro started the sled the next morning and took a little rip across the inlet. When he came back after 10-15mins, we noticed oil leaking out underneath. Just like you described, bellypan, airbox, filter all saturated with oil coming out the crankcase vent pipe.
That little black box that the crankcase vent line enters into in the airbox is called a water/oil separator. If some condensation freezes inside there it and doesn't get melted by the warming engine, I think oil pumping out is the result. Don't know if the hot oil would eventually unstick it but by then there might not be much left in the engine.
The good news is that you are the only other person on here that I know of whose had this occur. Now I always let the sled warm-up good before taking-off in or after really cold conditions. In the 3 winters since this has never happened again. At the time I was pissed but now I think I understand why it happened and I don't worry about it anymore.

 

[Vectornut]

Too much oil in the engine can do that. Use only 3 Litres (3.2 Quarts) provided you drain all the oil and replace the filter too. Also, note that the tube coming into the air box has a slit in it. This is to relieve any preasure at the end of the tube when ice is blocking it. This was found to happen on the first RX1's which caused them to burn oil and make a mess. This simple fix continued on to the Vectors. 05 RS Vector ER.

 

[Canadian Lad]

I discussed this with a mechanic and he told me the Vector is really a motorcycle engine developed imto a snowmobile engine and that motorcycles have this problem. He said there is a check valve that is opened by pressure inside and if this sticks closed (more than likely due to condensation especially in very cold weather) the engine has no place to dump the oil so it blows it out this tube. After I shut the engine off the heat from the engine and oil was enough to clear the problem and all is good then. He also said it is more likely to happen first thing in the fall after sitting for awhile (warm moist air freezing in the engine) or if the engine is started and not let warm up and then shut off in cold weather. On motocycles many guys remove the valve and this never causes a problem so he said if it contiues to happen it is something I might consider, if not not to worry about it.
I did have the engine started a couple of days earlier to load it on the trailer and it was not nearly as cold - possibly I did not warm it up enough and condensation formed. I have also noted more condensation forms in the aluminum trailer especially after a warmer day and then it turns cold. At times the entire inside of the trailer is coated with frost and at other times you can see where it has melted and dripped down when it warms up during the day. I imagine the same thing happens to parts in the machine.

No the engine was not overfilled with oil - it was at the correct level after the oil and filter change (3 litres) and the tube into the air box was not plugged as that is how the oil got into the air box.

 

[woolyviper]

i left a hose off of the airbox and it just kept pumping oil out the hose

 

[Canadian Lad]

i left a hose off of the airbox and it just kept pumping oil out the hose

That is a different hose and it is under the airbox. The one I had the oil coming out of is a vent hose inside the airbox.