crank case vent
Seasoned HDF Member
Joined: Jan 2013
Posts: 10,637
Likes: 1,246
From: Lake, Ms
2010 Limited with some stuff
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
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From: TOAK western branch
More like 25% SF. Water does a good job of steam cleaning as well.
Road Master
Joined: Jun 2014
Posts: 1,219
Likes: 63
From: westland Michigan
Since nobody else caught it what air cleaner do you have? A aftermarket one? If so you need to tune it somehow or other, you are running lean and or very lean. Plus it will run better with a tuner.
Batman
Batman
Seasoned HDF Member
Joined: Jan 2013
Posts: 10,637
Likes: 1,246
From: Lake, Ms
Ok thanks. I will give this a shot.
Yes I caught it but sometimes it's just not worth the effort.
2010 Limited with some stuff
2010 Limited with some stuff
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,488
Likes: 30
From: Maryland near DC
if you run a good high quality high test gasoline the engine will clean itself up SOME with time, seafoam is faster, but I have found that running good gas and long highway miles does just as good a job.it will never be as good as new, but it will get better with time..the back of the intake valves will get real clean pretty fast, it is the piston and cylinder head parts that take longer to get clean...
Outstanding HDF Member
Joined: Mar 2009
Posts: 2,216
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From: Central Illinois
I know people don't want to listen to this, but if the engine is operating properly you will get very little oil in the intake system and it won't build up on the valve stems. The vent system should not be pumping oil in to where it is running out the air filter or building up on the stems. Every automotive engine out there since the '70's has been running the same vent system and it has not been any sort of a problem. In fact modern automotive engines are some of the cleanest running engines ever, still venting to the intake.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
Ultimate HDF Member
Joined: Mar 2012
Posts: 6,129
Likes: 143
From: Santa Cruz
I know people don't want to listen to this, but if the engine is operating properly you will get very little oil in the intake system and it won't build up on the valve stems. The vent system should not be pumping oil in to where it is running out the air filter or building up on the stems. Every automotive engine out there since the '70's has been running the same vent system and it has not been any sort of a problem. In fact modern automotive engines are some of the cleanest running engines ever, still venting to the intake.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
While this is mostly true, those two big Harley Pistons going up and down basically together create crankcase pressure problems that auto and most other engines don't have to deal with. The new vent system is pretty good but it can't keep all the oil in there.
Stellar HDF Member
Joined: Feb 2010
Posts: 3,394
Likes: 263
From: Southern California
I know people don't want to listen to this, but if the engine is operating properly you will get very little oil in the intake system and it won't build up on the valve stems. The vent system should not be pumping oil in to where it is running out the air filter or building up on the stems. Every automotive engine out there since the '70's has been running the same vent system and it has not been any sort of a problem. In fact modern automotive engines are some of the cleanest running engines ever, still venting to the intake.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
Large amounts of oil into the intake is a direct result of too much blowby or bad or broken vent system in the rocker boxes.
Last edited by Bluehighways; Apr 30, 2015 at 07:11 AM.
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Seasoned HDF Member
Joined: Jan 2006
Posts: 11,471
Likes: 2,998
From: Charleston, SC
Very True. In fact, making the modifications suggested in this thread amounts to changing a Positive Crankcase Ventilation (PCV) system into a 1950's and prior Road Draft Ventilator system. Road Draft Ventilator systems ingest dirt into the Crankcase and do not purge the Water that condenses . . . the results degrade the oil and accelerate engine wear. . . for absolutely no useful purpose . . . sometimes the pseudoscience posted on this forum is beyond the pale!
No matter where the oil mist is directed, our engines are still positively vented... not pale pseudoscience.
For the others... Anyone that doubts what all this oil will do overtime (regardless of how well the engine is operating) need only open a head after 1000 miles on a brand new engine.
You will be amazed. Amazed... It's a mess.
Just pull the intake and look at the intake valves... black flakey paint looking chips all over.
Last edited by lp; Apr 30, 2015 at 07:55 AM.
Road Master
Joined: Jun 2006
Posts: 894
Likes: 6
Comparing crankcase blow-by from a Harley to an automobile is comparing apples and oranges. Most autos have most their sensors upstream from the PCV intake. Harley's have the PCV ventilating at the mouth of the throttle body. Everything after that is getting misted in oil. To the nah-sayers it's real simple to see, don't have to take the heads off. Just take the AC off and look deep inside the throttle body with a flash light. Hmmm looks ok you say? Now spray some MAP sensor cleaner in there and watch all the goo run down. Most of us guys with the 88CI have to clean the IAC every year.