I have a 1997 Fatboy that I recently bought with 43K miles on it. I had the dealer service the bike including cleaning the air filter. During a ride yestereday I noticed that I had oil dripping from the air filter. They may have put oil on it after it was cleaned. My owners manual says not to put air filter oil on it. Will this hurt the performance and should I reclean it myself?

I can not see any other reason why I would have oil coming out of the air filter. Any ideas here?

Foot

 

blow back from the breathermost prob, take your cover off & give it a clean, happens sometimes on a long run to me

 

One of the main causes for oil getting in the air intake is too much oil in the oil tank.

The dealer may have put too much oil in your tank. On your year bike, you should check the oil level when the bike is sitting straight up and off the jiffy stand, with the engine up to operating temperature.
I don't know exactly which model year that they started checking the oil level while the bike is on the jiffy stand, but I know it is checked on the jiffy stand, from my 2005 and newer models.

Some owners run 1/2 quart low to elminate sucking oil into thir air intake. It wont hurt anything running 1/2 qt. of oil low.
Tom

 

Agreed that it is almost certainly from the breather, and I hear on this forum that it is fairly common. Luckily, I've never had much more than a stain on the filter element and a film inside the ham can. No, you don't want to oil the factory element like the foam ones in a lawnmower. Yes, the factory filters can be washed with water and detergent (I use dish soap, and replace the filter with a new one about every 4th time).

Wet sumping can make a LOT of oil come out of the breather, and that makes sense to me. (Bike sits long enough for oil to drain from the tank into the crankcase, and blows everywhere before the scavenge pump can pump it out).

I regularly hear the "too much oil in the tank" story, but can somebody tell me how this can make more mist coming out of the vent tubes?

Is it pushing foam up so high in the tank that the tank itself is venting into the crakcase? That would have to be WAY too much oil in the tank, like somebody added 2 quarts to bring the tank back to full when the bike was already full but wet-sumped. I don't see how more oil in the tank can increase flow through the primary oil pump (same volume per revolution of the gearrotor. So what makes it more likely to come out the breather?

 

If you have an aftermarket air filter (k and n) then you should clean it and oil it. Take off your air filter cover and see what is behind there. Stock air filters should not be oiled as they are paper.

 

Thanks for all the information. I just had all the fluids changed at the Harley dealership and they added 3.5 quarts of oil so maybe they overfilled it.

As for the filter it is metal mesh with a paper filter inside the mesh. I believe this is the stock filter.

 

3.5 quarts may be a but much for an EVO or TwinCam and the odds are that its leaking back down into the crankcase when its sitting causing the breathers to spray oil into the filter. Paper filters and oil DO NOT mix well at all.
When its over full it takes a little longer to pump itself dry and that's all the time it needs to make a mess. Once the filter is gummed up it will actually make things worse. By restricting the air flow it will start trying to suck air through the breather tubes making a bad situation worse. Its not likely to cause anything like real physical damage, but it can rib the engine of performance and gum things like the plugs up.
One way to permenently stop it is to replace the breather tubes in the intake with an external breather filter kit. Then it can't suck oil and oil vapors into the intake clogging things up on you.
It ain't exactly EPA friendly, but your bike is old enough not to worry and who cares what they think anyway. You want the bike to run properly without making a mess all the time or costing you a small fortune in replacement air filters.

 

Oil is checked upright, level, at op temperature for this yr/model. Small amount of oil is normal esp in 75 degree & up weather as the breather has a tendency to puke on EVO's. There are ways to lessen this occurance by proper carb adjustment but too soon for that. Why not enjoy the new bike for a while first and, meanwhile, you could go getja a service manual?

 

if it is a cleanable reusable hi flow air filter then yes it needs to be oiled. Mine uses K&N red oil and it will stop dripping after a while. Also if they over fill the motor oil it will drip for a while

 

this happened to me last summer. i took bike back to the dealer who did my scheduled service and the original tech had overfilled my oil way too high....once they pulled the oil out and got me back to normal oil level i was fine and no oil was blown out back into the air filter from that point on. they also cleaned my filter