Oil in Air Filter
Stellar HDF Member
Joined: May 2007
Posts: 2,431
Likes: 38
From: Caldwell, Idaho
Just started "misting" on mine couple weeks ago....yep, standard answer "they all do that". I'm on extended warranty now, so can take it wherever a certified extended warranty indy is located. I'll ask about oil pump being out of alignment.
Oil changes were set to below the line to fix issue....huh, yeah, right. That worked for about 5K miles, now I'm cleaning oil off right side.
Oil changes were set to below the line to fix issue....huh, yeah, right. That worked for about 5K miles, now I'm cleaning oil off right side.
Road Warrior
Joined: May 2008
Posts: 1,513
Likes: 6
From: SC
When Harley was forced to finally seal their V-twins so they were oil leak free (which began with the Evo motor) the last problem they had was what to do with the piston blow-by oil, the oil used to lubricate the rockers in the heads, and that mix of oil and water (from condensation) that makes that milky brown sludge. The main problem is the return oil system from the heads just isn't effective enough.
They could have designed a catch system you have to empty occasionally but spread across all model bikes that would have been too expensive. So they used the band-aid approach. Shove it all into the intake system to (supposedly) be burned. It made the EPA happy but think about what that oily stuff does to a carb, or an EFI system, and your spark plugs.
And no, you shouldn't seal the head breather holes to stop the leaks and misting. The fact the mist comes out from there is telling you the return oil system isn't up to the job of relieving all the head pressures. Sealing these holes would probably result in gasket leaks elsewhere.
The best fix is either (if you're Green) build a catch can system, or otherwise just run both head breather hosed into one hose that drains to the ground.
The amount of oil in the oil tank does matter, but it's more about the amount of empty space above the oil level in the tank. These oil tanks really need to be vented to outside air pressure but Harley was loathe to but another hole in the system that could leak oil.
Harley may never solve this problem without ditching the current push rod setup. And I think most of us are glad they haven't changed to an overhead cam setup for traditional and aesthetic reasons. But if you ever owned a Shovelhead motor this misting problem on Evos and TCs isn't really that big a deal . . . until you have to clean it up, LOL!
They could have designed a catch system you have to empty occasionally but spread across all model bikes that would have been too expensive. So they used the band-aid approach. Shove it all into the intake system to (supposedly) be burned. It made the EPA happy but think about what that oily stuff does to a carb, or an EFI system, and your spark plugs.
And no, you shouldn't seal the head breather holes to stop the leaks and misting. The fact the mist comes out from there is telling you the return oil system isn't up to the job of relieving all the head pressures. Sealing these holes would probably result in gasket leaks elsewhere.
The best fix is either (if you're Green) build a catch can system, or otherwise just run both head breather hosed into one hose that drains to the ground.
The amount of oil in the oil tank does matter, but it's more about the amount of empty space above the oil level in the tank. These oil tanks really need to be vented to outside air pressure but Harley was loathe to but another hole in the system that could leak oil.
Harley may never solve this problem without ditching the current push rod setup. And I think most of us are glad they haven't changed to an overhead cam setup for traditional and aesthetic reasons. But if you ever owned a Shovelhead motor this misting problem on Evos and TCs isn't really that big a deal . . . until you have to clean it up, LOL!
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,419
Likes: 6,366
From: Honah Lee
My previous bike (Yamaha V-Star) vent system dumped into the air box similar to my Harley. Were it differed was it was into a cupped area that has an opening toward the intake. However at the bottom of it was a simple attached hose that led out the bottom of the air box and down about 2" with a simple cap on it. What was interest to me was no were in the owners or service manual any mention of it. However at about 6K when I did the first service (about 5K later then service manual said) I realize it was a drain. Had a good hand full of oil stored up in in and some had spilled over in the air box. However the lower air box was sealed well enough that it did not drip out. Here in VA my local typical Shell Station VA inspector checks my bike actually look with a small flashlight behind my air box. I did not ask him what he was looking for. He actually peered into a lot of areas with the flashlight. Some of them I think he may have been just making it look like he knew what he was doing but he shakes his head and smiles and seems to enjoy walking around it for a few minutes and then taking his $12. and pastes the new sticker on my plate. Guess it beats removing a 3TON cager wheel
Outstanding HDF Member
Joined: Oct 2007
Posts: 3,178
Likes: 6
From: 50 Miles North N.Y.C.
Put 3000 miles on bike in past week. "Misting" is pretty bad. "Misted" 1 qt. Took off curved vent hoses and put on longer hoses routed to under engine. No more problem with oil on me and bike but underside of bike is dripping oil from "misting". This is crazy. Really thinking of plugging vent ports. Can anyone see a problem doing that?
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,791
Likes: 690
From: Smalltown,USA
Picked the Trike up today dealer told me not to over oil the K&N filter. When I told him it was a paper filter he just gave me a stupid look. He claims they found no problems. I am going to make a catch can and ride it until the warranty is out.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,419
Likes: 6,366
From: Honah Lee
That is a big part of it. Below 3000 and there is little problem. May see a drip in a month of 60mph. At 70 mph mine will have a drip or two after it sets a few days. I have the open SE filter. When I had the typical football cover, I ran a light day stuck to the lower bottom edge and it took care of it.
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