StromTrooper banner

1 - 6 of 6 Posts

·
Registered
Joined
·
97 Posts
Discussion Starter #1
DL 650 - It looks like the crankcase breather was letting engine oil up into the air box. The mesh filter was oil soaked and there was about a 1 or 2 tsps of oil in the bottom of the air box. I did a 250 mile ride the day before and was pretty hard on the engine but I wouldn’t think this would cause oil blow by. Looking for any thoughts on what if any usual suspects that could be causing this? I don’t want to have to clean that mess from the air box again. Thanks
 

·
Administrator
Joined
·
16,794 Posts
Are you "overfilling" the crankcase? I usually fill up to just below the top oil fill line.
 

·
Registered
Joined
·
97 Posts
Discussion Starter #3
Big B said:
Are you "overfilling" the crankcase? I usually fill up to just below the top oil fill line.
I probably should have mentioned it in my original post, my oil level is in the normal range (currently about ¾ up from the low mark). I’m starting to think that I was flogging the engine pretty hard on my last ride (windy mountain passes) that crankcase pressure was high enough to drive some oil up through the breather tubes. Doesn’t seem normal but it may be a likely explanation. Still looking for other thoughts.
 

·
Registered
Joined
·
86 Posts
My 650 went to the dealer for the first maintainence and came back overfull on oil. The level was in the sight glass with the bike on the sidestand on level ground. I corrected that at the time and the bike will not ever be going back to them, but a year later when I changed the air filter I saw oil in my airbox also. I suspect that overfilling might be the source of your issue, even if only slightly too high.
 

·
Registered
Joined
·
97 Posts
Discussion Starter #5
This oil in the air box thing has been bothering me all week and I think I may have finally figured it out. I completely forgot that about three weeks ago I had a low speed drop onto the left side (nearly 0mph with no damage, THANKS GIVI). The way the bike landed it was laying downhill about 10 degrees beyond horizontal. Since the crankcase breathers are located on the left side this more thank likely allowed engine oil to flow up the breather tubes. So remember, if you lay it down on the left side you may want to check that air box.
 

·
Registered
Joined
·
15 Posts
Interesting thought on the drop being the source of oil in the airbox.

I changed my oil a few weeks ago and the level in the glass was right at full. I had a drop on the left side a week later.

Last week, I went to change the air filter and found oil. Hmmm...

Since we are on this subject, does anything have to be done other than wiping up the oil? Does the breather element need to be washed?
 
1 - 6 of 6 Posts
Top