Fed up with oil in my air cleaner
Road Warrior
Joined: Jun 2008
Posts: 1,602
Likes: 3
From: Southeastern Michigan
I'm not buying the SE backing plate is junk. It does exactly what it was designed to do - provide unrestricted air flow.
The problem is, the vacuum created by the restricted stock filter is sufficient to pull the heavier oil mist into the intake tract, eliminating the problems that the aftermarkets can't (by design). The reason why a previous poster didn't have issues after an engine upgrade (upped compression) is that the motor pulled more vacuum.
A possible fix is the new style breather (in the heads) that Harley has been putting in late model engines? Other then that - run hoses to a catch tank as a previous poster and countless others have.
My 07 does it too, but it's never been that bad. The problem with the pre-08's is that the IAC is in the line of fire of that incoming oil mist, gets dirty, and fails. Creating idle problems.
The problem is, the vacuum created by the restricted stock filter is sufficient to pull the heavier oil mist into the intake tract, eliminating the problems that the aftermarkets can't (by design). The reason why a previous poster didn't have issues after an engine upgrade (upped compression) is that the motor pulled more vacuum.
A possible fix is the new style breather (in the heads) that Harley has been putting in late model engines? Other then that - run hoses to a catch tank as a previous poster and countless others have.
My 07 does it too, but it's never been that bad. The problem with the pre-08's is that the IAC is in the line of fire of that incoming oil mist, gets dirty, and fails. Creating idle problems.
Seasoned HDF Member
Joined: Apr 2012
Posts: 9,978
Likes: 5,218
From: Michigan
I know this may make some of y'all laugh but I used a plastic "T" to connect the two "S" hoses and put the end of the back towards the carb/throttle body on our bikes.
It didn't totally eliminate the occasional drip but it's far less than it used to be.
FWIW, I'm very careful to keep the oil as near to the full mark as possible so when we're traveling I check (and add) oil every day.
It didn't totally eliminate the occasional drip but it's far less than it used to be.
FWIW, I'm very careful to keep the oil as near to the full mark as possible so when we're traveling I check (and add) oil every day.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
Let me get this out of the way, I do not have too much oil in my crankcase.
Now, the H-D Stage 1 Air Cleaner backing plate is a piece of junk! My K&N filter is always soaked with engine oil every time I check my air filter which can't be good for the air cleaner material. Also, I do long rides in the order of 800 miles in a day so not only does the filter get soaked but I also get some oil dripping inside the football cover.
There is a vacuum port behind the throttle body butterfly. So here are my questions:
To end, my rant, sucking oil into the intake tract is a stupid idea anyway since oil presence can cause pinging issues and it just gums up the intake valve.
Input that answers my questions are welcome.
Thank you!
Now, the H-D Stage 1 Air Cleaner backing plate is a piece of junk! My K&N filter is always soaked with engine oil every time I check my air filter which can't be good for the air cleaner material. Also, I do long rides in the order of 800 miles in a day so not only does the filter get soaked but I also get some oil dripping inside the football cover.
There is a vacuum port behind the throttle body butterfly. So here are my questions:
- Is that port used by the stock air cleaner for crankcase ventilation?
- Is there a high performance air cleaner backing plate that uses the Stage 1 K&N air filter that has crankcase vent tubes that run to the vacuum port on the intake manifold behind the throttle butterfly and that let's me retain the stock football cover?
To end, my rant, sucking oil into the intake tract is a stupid idea anyway since oil presence can cause pinging issues and it just gums up the intake valve.
Input that answers my questions are welcome.
Thank you!
You say it causes pinging...humm that could explain a few things.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
I run mine right to the full mark and I dont hsve the dreaded drip so Im claiming BS on the oil level being the culprit.....we need input from someone who has devised a suitable collection device. I dont know about you but I dont want oil in my intake system at all!
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
I know this may make some of y'all laugh but I used a plastic "T" to connect the two "S" hoses and put the end of the back towards the carb/throttle body on our bikes.
It didn't totally eliminate the occasional drip but it's far less than it used to be.
FWIW, I'm very careful to keep the oil as near to the full mark as possible so when we're traveling I check (and add) oil every day.
It didn't totally eliminate the occasional drip but it's far less than it used to be.
FWIW, I'm very careful to keep the oil as near to the full mark as possible so when we're traveling I check (and add) oil every day.
Elite HDF Member
Joined: Apr 2012
Posts: 4,474
Likes: 2
From: Puerto Rico
I did away with all that plumbing/venting crankcase fumes/oily mist back into the intake. Rigged my own set-up with "T" to a little breather-filter under my throttle body, Does NOT show, but can check it easy.
Waiting on BREATHER BOLTS (on the way) for Twin Cam finally! Then everything comes-off.
Waiting on BREATHER BOLTS (on the way) for Twin Cam finally! Then everything comes-off.
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Tourer
Joined: Sep 2006
Posts: 289
Likes: 53
From: New Oxford, Pa
I think Harley changed the rocker box oil breather seperators in 2011 to a new stamped steel version. The nylon fiber media inside, is not sitting in oil any longer and it breathes better. I changed my 08 and routed the breathers to the ground and the only thing I see is moisture coming out.
Cruiser
Joined: Apr 2012
Posts: 210
Likes: 1
From: Arkansas
You havent died yet either, does that mean the ones that have its just BS
Its not BS, ive seen alot of people that had this problem solve it just by dropping their oil level by 1/2 qt. My 06 did it from the time i left the dealership, i had another dealer tell me to change the syn oil out put dino oil back in it and run it 1/2 qt low, problem solved. Running it 1/2 qt low does not mean you dont have enough oil in the engine, as long as your oil level is between the low mark and full mark you have plenty of oil. I agree HD should have fixed this problem along time ago, but they didnt and riders have found ways that work for them to stop it. If you google it there is a company that makes a nice little chrome catch bottle that bolts well im not sure exactly where it bolts to, around the cleaner someplace that looks good and catches the oil, just empty it once every 6 months or whatever.