Looks like a small oil leak from the bottom of the head gasket. I don't know the cause, but for the first time ever, the coolant reservoir was empty. I topped the reservoir off and a lower hose leaked out the overflow.
Topped off the oil with 1 qt. This is the first time ever that she lost any oil.
So I'm going to start doing the research on what I need to replace the head gasket.
I'd like to do a leak down test and I assume the head should be resurfaced. The gasket is about $60 and a gasket kit seems to be just over $100.
She's at 38,000 miles now, so the valve check/adjust will happen.
Questions are about what all I should get into. Cam chain tensioner etc?
I know that some have written up on the throttle cable and how to remove the air box, but don't remember seeing any full head gasket job.
I'm assuming the engine can stay mounted while the head is removed, but is it worth it to keep it mounted?
It's a stressed member of the frame, and I don't know how to replace one that is stressed, never done that type of engine before.
Is the leak a sweat/ooze or a leak that dribbles?
Is it on the right side as you side on the bike?
Keep in mind that the oil feel to the head is a single feed from the block upwards right beside the chain drive cavity.
Have all the oil level checks been consistent, and based on both wheels on the ground and bike balanced nicely?
(thus begging the obvious question about the practicality of doing oil level checks in general LoL ?)
The factory service manual is pretty good.
While Leak Down Tests can reveal much, IF you only have a gasket failure at the oil feed to the head, a L D T will not be helpful.
Don't surface the head unless it is out of plane and/or damaged.
Cam chain tensioner should not be an issue.
I think you are right, but at least the factory service manual is good.
Yes it can.
Why take it out if you don't have to.
The 919 engine is not fully stressed member, just partially.
It should be an easy in/out operation but force more scope of work that is not necessary and offers zero benefit.