Oil Into Airbox

On a maybe related note, I did just install the reed check valve.

Took the bike for a ride and found that the hose that goes to the bottom of the airbox was spitting some oil.
What could cause this?

Bike is a 75 850 Commando.

Thanks

jaguar said:

Took the bike for a ride and found that the hose that goes to the bottom of the airbox was spitting some oil.
What could cause this?

Bike is a 75 850 Commando.

Click to expand...

There wouldn't normally be a hose going "to the bottom of the Mk3 airbox" so I think perhaps we need more detailed information?

The standard Mk3 oil tank breather connects to the oil separator (see drawing, below) this has a connection to the airbox but it's about halfway up on the rear LH corner (see photo), however, if there is a significant amount of oil coming from that hose then it's possible the oil tank was overfilled.

I fat fingered a key.
Bike is a 74.


Can see the hose in the upper right.
mounts fairly low on the back of the airbox plate.

jaguar said:

Bike is a 74.

Can see the hose in the upper right.
mounts fairly low on the back of the airbox plate.

Click to expand...

That hose would seem to be the "engine breather" which if it is, would normally connect to the spigot on the oil tank filler neck.
The "oil tank breather" connects to the spigot on the airbox

And, as L.A.B. said in an earlier post, it may be as simple as an over-full tank. I usually keep my '74 towards the "Lo" mark for this very reason.

Nathan

You have a K&N filter, so more oil won't hurt it. As Nater mentioned keep the oil level at the lower mark on the dip stick after you have run the bike for a while to get all the oil pumped into the tank.