Hot Oil Smell

[Tominator]

This is my second Boxer. Both now have an Oil smell while driving after 20-30 minutes. Sort of like my old econoline van with leaking rocker covers. Covered the obvious, not overfilled, no oil leaking anywhere...I suspect its blow by? Both had (Have 80,000KM on them)

 

Anyone else ever notice this on their bike? Something else I should check? I know the crank is vented, and IMHO it must be oil reintroducing itself into the intake? Any way to confirm or fix?

 

Tomas

[Ken H.]

Two thoughts. Are you sure there is not slow drip? Even from the transmission onto the catalytic, or something similar? It takes very little.

 

Secondly, there is a drain in the air box, lower left rear corner. Open it and see if any oil comes out. Seems to be the place where it collects if the bike has been overfilled with oil and some gets drawn into the air box via the crankcase vent.

[E30TECH]

I get the same thing. My bike has 8300 miles, still uses oil, but I dont see a leak.

[powerman]

Does it smell a little more like road tar? i get a lot of asphalt thrown up onto top of the Catalytic converter. Take a look to see if you a pile up in there.

[ninermatt]

There is a breather on the upper right side of the motor that vents via a rubber hose to the air box I wouldn't be surprised if it where cracked or deteriorated and or disconnected.

[sonofdennis]

Yep, I get the same smell. Annoying.

[Tominator]

I don’t have a Cat. Replaced the exhaust with a Staintune! But no there is no leak. I know the crankcase is vented into the oil box...I never fill my bike OVER the halfway mark...based on all the oilheads I've owned. It’s the oil level sweet spot.

 

I was thinking like the K bikes, they have a hose that cracks with age/heat and starts to smell. I never looked at it closely but I was under the impression our Oilheads vented back into the air box directly through the casing?

 

Tomas

[Tominator]

Ah yes...confirmed on my pdf file. There IS a little Hoser there that connects the crankcase to airbox. I'll check it over the next few weeks and report my findings. It doesnt smell like burning oil, but blowby....

 

Thanks to all!

 

Tomas

[realshelby]

My '04 RT had a wierd oil/blowby type smell I would notice when stopped at a light or parking the bike on occasion. Turned out the be the transmission rear input shaft seal leaking. Gear oil migrating onto the clutch has that smell when the clutch gets hot! You might be able to pull the clutch slave cylinder and check if you become suspicious of this area.