Hi guys. I’ve been doing all of my basic maintenance on my 08 Electra Glide Classic thanks to your videos. I noticed today that I have some oil dripping from my Harley air cleaner housing onto the right side of the motor. It’s not much, but I’m concerned. No recent service to the bike except for a new battery a couple of weeks ago (I installed it). It hasn’t been dropped or on its side. The oil level is right where it should be on the dipstick when cold. I’ve done all the fluid changes and am very careful not to overfill. Any help would be appreciated.
Top breathing engines breath, or vent, through the top breather bolts which are threaded into the heads of a Harley Davidson motor. The air inside a motor is saturated with oil. It exits through the breather bolts and into the air box where the air is filtered and the oil is captured in the air filter. A larger motor or a built motor will, typically, breath heavier. When oil drips out of an air cleaner assembly, it is usually an indication that the air cleaner element is due to be cleaned, or changed.

Check out these related videos:
Air Intake Installation
Rocker Breather Replacement
Another Rocker Box Breather Swap
and please feel free to share and comment below!
More Info:
Here is an article we like from MotorcycleCruiser.com. It explains why you had oil pumping out if your air cleaner assembly. The only other reason for this to happen can be from a broken oil pump or overfilling, as you mentioned.
Understanding Blowby in Motorcycle Engines
If you ride your motorcycle too gently early on, you may never get the piston rings seated. Then Bad Things happen…like blowby and oil where it doesn’t belong. From the April 2005 issue of _ Motorcycle Cruiser _ magazine. Read on for the causes and every now and then I receive an e-mail from someone wondering why he’s suddenly finding large puddles of engine oil in his air filter. While some oil misting in the air filter is normal and nothing to worry about, these guys, who invariably own large-displacement, high-mileage V-twins, are talking about a regular Exxon-Valdez, enough to make a real mess and require topping off the oil supply on a regular basis. Because this is an area of general interest, let’s discuss what’s happening.
By nature, all four-stroke engines require ventilated crankcases. The reason is twofold. First, when an engine is started or run at low temperatures, condensation takes place and fuel vapors migrate into the crankcase. These contaminants, essentially water and raw gasoline, mix with the oil to form engine-damaging sludge. Fortunately, once the engine reaches operating temperature the water turns to steam and the fuel remnants percolate out of the oil. As long as the crankcase is vented, either by the atmosphere or by using a positive-pressure system, these nasty byproducts are free to drift out of the engine and go their merry way without causing any harm.
The second reason the crankcase needs a vent is because no matter how hard we try, there is no practical way to eliminate air from entering it. Anytime the engine isn’t running, atmospheric pressure pushes air into the engine through open valves or any other convenient entry point. When the engine is running, some combustion gases normally make their way past the rings to pressurize the crankcase as well. If the crankcase wasn’t vented, pressure buildup would soon cause every seal in the engine to rupture as the trapped air sought a way out.
Originally, crankcase vents were nothing more than tubes connected to valves timed to open when crankcase pressure was too high and close when crankcase pressure was too low. This allowed the bad stuff to be forced out and prevented dirt from being drawn back in. A variation on this scheme vented the crankcase through a series of baffles, accomplishing the same thing with less complication. Although they were efficient, these breather-tube ventilators were little more than open pipes spewing engine contaminants directly into the atmosphere. As you can imagine, the EPA took a dim view of the situation and demanded that manufacturers, first car and later motorcycle, do something about it.
Although system details vary, one solution was to plumb the breather into the air cleaner. The fumes coming from the crankcase are then recirculated back into the engine and burnt.
Here’s how the oil ends up in the air cleaner. Crankcases can only contain a given volume of air and its attendant pressure. Once that pressure is exceeded, you’ve got problems.
What causes excess crankcase pressure? Excellent question, grasshopper. For starters, anything that can reduce the crankcase volume, such as overfilling it with oil, creates problems, as will a restricted or damaged breather system. In V-twins, crankcase pressure sees rapid fluctuations, decreasing as the pistons rise in unison, then increasing sharply as they descend, compressing the gases in the crankcase. But the most common culprit is usually something called blowby.
Blowby occurs when the piston rings fail to do their job properly. They may be worn or they may never have seated properly in the first place. This failure to seath the rings tends to be somewhat common is large-displacement V-twins. That is partially because they make good power down at low rpm and small throttle openings. However, it takes large throttle openings and high rpm to get the rings seated. If you went through those first few hundred miles without ever holding the throttle open or revving to the power peak—or only did it once or twice—your rings probably never seated.
The bottom line is that the piston rings can no longer effectively seal the combustion chamber. Combustion gases are leaking past them, pressurizing the crankcase. This creates all kinds of problems; seals leak, gaskets fail and, because the pistons are forced to compress the excess air on the downstroke, horsepower is lost. But these things don’t happen right away.
Because the hot oil in the crankcase is easily displaced by the increased pressure and because it has a perfect path out of the crankcase via the breather, the first sign of impending trouble is nearly always oil migrating into the air filter.
Once the oil is pushed into the air cleaner, much of it condenses and drops out of the airstream, making a mess in the process. If this was the only problem it’d be bad enough. Unfortunately, some of the oil is pulled back into the engine along with the vapor and burnt, where it does more damage by glazing the cylinder walls and creating carbon deposits in the combustion chamber. At this stage the engine is on a downward spiral. It’s only a matter of time before you’ll be doing a top-end job.
I’d be remiss if I didn’t mention that some engine designs are more likely to experience top-end sealing problems and/or breathing issues than others. In particular, large-bore twins, V or otherwise, tend to push more oil than an equivalent-displacement multi. This is simply because dinner-plate-size pistons moving through sewer-pipe-dimension bores are more difficult to seal and move greater volumes of air. As a side note, there are also some bikes with poorly designed breather systems, but that’s a separate issue to be discussed another time.
Please don’t get the mistaken impression that all large twins are just ring-eating monsters waiting to self-destruct; they aren’t. Chances are the majority of us will never have a problem with blowby. But like they say, recognizing a problem is always the first step in curing it.
I have the same problem, and yes, my filter does need to be cleaned. I have an after-market spike filter. The breather bolts feed into a secondary filter to collect and filter the oil, but it has started dripping onto the bike recently. I’ll clean both filters and see if that fixes the problem.
Hi Tom, Thanks for the post. Send a pic and let us know how it goes.
have 94 fatboy with S&S reed valve and S&S catch can only way to go
If its a k /n air filter it may be over saturated or over charged with oil if it was cleaned
It’s likely you have too much oil in the crank, check your oil hot and have the level remain at the half way full mark or just slightly lower.
I have the same issue, a few months ago I changed the stock air cleaner to a K & N element. At the same time I removed the backing plate and painted it to match the denum paint! Put everything back together, minus the ugly football cover..I replaced that with a medallion which I love. Ever since than I have had dripping oil that as I go down the road gets all over the sattle bag, the oil is right at the correct level…very frustrating. I also cleaned the filter, and no change. What to do??
Hi Greg, Thanks for the comment. If it did not leak before, that tells us it’s something with the install or new product. If it’s excessive and not performance related like this post indicates, it can be a leaking breather bolt. We have several Air Intake install videos in the Style and Performance section to review. http://www.fixmyhog.com/video/arlen-ness-air-cleaner-install-003256/
I had same problem on my 113CI motor. Installed “demysters” which solved the problem. The venting bolts do not do the job on bigger motors especially on longer sustained speed rides.
Thanks for all above…I just changed the battery (got stuck at the gas station)- then went out for test drive afterwards- and sure enough, the engine light came on- has to turn back- then I saw the oil stains on the cleaner bottom and bottom of the “V”…no oil elsewheres (line was good, etc.)…so I took off the cleaner, and yep, all in sode at the bottom, and at the ends of both breather tubes had a CL2 leak. With the cleaner off, I started the engine, revved it up to 3K and and idled, and the engine light went out…so….I hoping its “just” the cleaner. I have an ’07 Electra…I’ll let you know when I get ‘er changed- thanks all! Really, thanks!
TRY DROPPING YOUR OIL LEVEL DOWN ABOUT A HALF QUART PROBABLY SOLVE THE PROBLEM MOST ALL OF THE TOURING BIKES I HAVE OWNED WILL DO THIS IF IT IS FULL OF OIL BETTER ABOUT PINT LOW WILL DO THE TRICK
I just upgraded my intake to a Screamin Eagle Stage 1 intake. I run the filter with just a medallion instead of the full cover. Knowing that my bike leaks a lot of oil, I had considered routing the breathers to a tube with a filter on the end, to the bottom or rear of the bike. I’ve read that cold dry air is better for the bike. Creates more power, and would reduce carbon buildup in the chamber and on the piston, but I’ve also been told that the oily mist also lubricates the top side of the piston. Which would you recommend. Rerouting or not?
Hi Tyler, How much is a lot of oil?
I ride from Oceanside to San Diego and back 3 times a week, and my regular rides to work. Every 2 weeks I’m adding between half and a whole quart.
If you will run with the oil at 1/2 quart low it will help. You still have plenty oil for the engine. As the oil heats up it will expand & can become over full. The oil is a normal Harley happening. I use a sanitary napkin (liner) in the lower portion of the air cleaner & change it out with each oil change. It keeps the oil off the engine.
The only other option is to put an external breather kit on to keep the oil out of the air cleaner. This is a good idea also because it will help prevent carbon build up in the combustion chamber from oil deposits.
Thanks Mark. I will try it.
Hip guys I also have the same problem I have a 2002 road king cvo 1550 with 90,000 miles and just recently I guest in the last 6 months started to drip oil from the air breather. It has a Rinehart exaust with and efi and a k & n air filter. My question is any ideas on what can I do to stop leak.
Hi, Ramon. The oil is residual from your engine breathing/venting. You can not prevent, or restrict this from happening.
We suggest removing & cleaning your air cleaner element more frequently. Wash your K&N filter in warm, soapy water. Dish detergent works best. Then, blow it out with compressed air and let air dry.
Thx I will do that this weekend and see how it goes
Same problem on a 2012 ultra.tried running low oil didn’t work just junk harley internal parts.
Don’t blow out with compressed air! You will ruin the element. Shake the filter and them let it air dry.
Phooey… As long as it’s not high pressure, keep it to 10-15 psi, it’s fine. They also say not to use heat guns or blow dryers, but fine. On medium heat & high speed, it’s still way less heat & velocity than the element experiences during normal riding operations. A little 90-100 degree low pressureair (low enough to not compress the fibers, is perfectly fine. Hell, same exact media for diesel rigs, K&N replies you to use a pressure washer & compressed air.
You can use compressed air, just don’t have the nozzle right up against the filter element
If anyone can help me out I’d appreciate it! I have a 2000 Road King, just recently it started leaking oil out the air filter. I took it to the dealership and they told me my rocker seals were leaking, I had them replace it and also do a 40k service. Not 48 hrs later still did the same thing, took it back to the dealer and they than told me that an oil port in the head was clogged and the air filter housing was warped, so again had that all replaced/fixed. Another 48 hrs later still leaking, also it only leaks at highway speeds 70+ mph. Now it’s back at dealership and now they are telling me that the cam chain tensioner went and made the oil pump fail! Please help me!
Desperate
Hi, Hwan. The dealership is approaching this the correct way. The reason they went into your rocker boxes was to replace your breather valves.
If breather valves are bad, the motor may breath too heavily into the air cleaner assembly. At 40k miles, it is a logical thought that the breather valves may be blocked, or no longer functional. Next logical step would be going into your cam compartment to inspect your oil pump.
Going by what you have told us; seems like they are on to your problem.
Fire that money sucking dealer! He is ripping you OFF man! Just check the air filter regualtly keep it clean and run a little less than half full on the dipstick? How much did the dealer scam you out of? Please post this POS dealer so we can all stay away
Quit taking it to the dealer.
I have a 2002 Road King with an Arlen Ness big sucker air kit. After every ride I need to remove the air filter and wipe down the inside of the throttle body as well as the standing oil on the air filter element. I cleaned the filter as per the Arlen Ness directions but the problem still exists. I run the oil level about 1/2 down the stick as recommended. I have had a machinist friend of mine make new breather bolts for the air cleaner with venting out the top of the bolt to a fitting that will have a stainless steel hose venting under the bike. My question is can I block off the existing venting to the air cleaner so that now blow by gets to the air cleaner/throttle body. Will this affect engine performance or wear? does the engine need the vaccuum produced by the opening of the throttle body to work properly? Brad
Routing you breather line(s) beneath your motorcycle is fine. Just make sure that the engine’s breathing/venting is not restricted in any way.
You do not need to have your engine breathing into your throttle body/carburetor. It is only that way for environmental reasons.
Thanks, I’ll complete the install. Brad
I was thinking of installing Vance & Hines VO2 Naked Air Cleaner, the breather tubes are directed back through the throttle body is that better than a breather kit? My concern of the kit is the routing of the drip hose so that oil isn’t dripping on the rear tire.
My 95 Evo was leaking from what I thought was the rocker boxes. It actually leaked for a year before I found the real problem.
I always thought it was the front rocker box leaking and changed gaskets twice myself and had harley change once to find the same problem after hundreds of dollars. I went on fix it sites and no one mentioned that your lower frontlegs where they are put together with a seal and retainer ring can leak and spray a fine mist from the front tire and always looks like the front box is leaking. I noticed a very fine mist on my front fender but I thought it was from the box shooting oil,
One day I decided to look into stiffening the front tubes so I pulled the front end apart and low and behold the seals where leaking. It cost me $100.00 and not one leak after a month!
I have a 1999 1200XLC. I am having a lot of oil dumping into my air cleaner. air filter replaced and even removed filter and still dumping oil. any ideas?
Make sure your oil tank is not overfilled.
Otherwise, you may need to open up your rocker boxxes and replace your breather valves.
http://www.fixmyhog.com/video/fluid-service-clutch-primary-chain-adjustment-001223/
http://www.fixmyhog.com/video/roland-sands-rocker-upgrade-install-007560/
I have a 99 fatboy and made the mistake of letting someone change my oil. Gift card for a service. Anyway they over filled my oil and they filled it to the top I put about 30-40 miles on it and it stald on me. I noticed oil coming from air filter. I cleaned my K&N filter and changed the plugs. Still does not start, any suggestions on what to check or do. I am going to do a compression test next.
We would suggest draining/correcting oil level and new spark plugs to start.
http://www.fixmyhog.com/video/oil-transmission-fluids-001266/
Had blow back oil was overfill when oil change was done. I put about 30-35 miles on it and it stald on me had blow back. So I cleaned air filter(K&N) and changed plugs. Bike still will not start. HD Fatboy 99′
Hi Edward. M/C not starting may not be related to the oil overfill. Check for spark and verify weather or not you are getting fuel through the carb.
http://www.fixmyhog.com/video/harley-davidson-ignition-coil-test-008707/
http://www.fixmyhog.com/video/cv-performance-products-review-006950/
http://www.fixmyhog.com/video/performance-carburetor-kit-001427/
I picked up a 98 road king i was told in 2010 the evo engine was replace with the same crate size 80 ci evo my problem is it leaks oil out the front breather vent i took rocker box off the mushroom oil deflector was in the wrong place i put a new one in the rite place put back together same leak so i took off cam cover the breather gear was broke i replaced it put back together still leak, when i say leak i mean after 1/2 minute to 1 minute it will start leaking and wont stop till i shut it off then drains for a little bit more
I have a 2011 FLTRU and recently upgrade with true duals, free flowing breather/ filter and a download to tune the bike up. I typically run my oil a little low to help prevent the oil from dripping out the breather. And it still has some excess dripping. I was told by the local bike shop not to worry about that with all the air flow I have going through the motor that is normal. I haven’t had to add oil between oil changes. It’s just messy and and smelling oil makes me think I have other issues. I am looking for another opinion. Thanks
These motors breath heavy and are air cooled. The build up of oil mist in the air cleaner assembly is normal.
We would suggest, more frequently cleaning the air filter. It’s quick and easy.
Definitely would not suggest running the oil level low. Less oil = less cooling
http://www.fixmyhog.com/video/high-flow-air-cleaner-install-w-cabless-throttle-body-control-review-001342/
http://www.fixmyhog.com/video/air-cleaner-upgrade-001297/ (ZD: 3469)
I was told that new backplate design on the K&N intake will help stop almost all of the oil leak from the air cleaner because they are placed farther in the backplate
It is a better design but you will still have to service your air cleaner element on a regular service schedule.
Some bikes will breath heavier than others
http://www.fixmyhog.com/video/air-cleaner-upgrade-001297/
http://www.fixmyhog.com/video/twin-cam-103-harley-davidson-air-filter-element-service-009155/ (ZD: 3778)
I have a 2015 Road King, with the Vance & Hines CA fuelpak, an S&S Teardrop air cleaner, and Samson Cholo slip-ons. I put all of those items on at around the same time. I started getting the air cleaner dribble, and contacted customer service at S&S. They said the air filter element may have too much filter oil in it, and to clean and “lightly” re-oil the filter. Which I did. And it started dribbling again within two weeks of commute riding. My mechanic says that’s just how it is, but is that really true? I sure as hell am not going to service my air filter every two weeks. I’m tempted to put it back to stock and see if the leak continues. Also, does that tampon idea really work? That sounds reasonable.
Hi Tony. Some motors will breath a little bit more than others. Nothing is wrong. Definately not something you will want to deeply investigate, as that will become very expensive.
Your motor will breath the same with your stock assembly. However, your stock air box may do a better job of capturing the oil mist and directing it into your throttle body.
You can also try a different high flow air cleaner assembly, although the S&S assembly that you have is excellent.
https://www.fixmyhog.com/video/high-flow-air-cleaner-install-w-cabless-throttle-body-control-review-001342/
https://www.fixmyhog.com/video/harley-breather-intake-upgrade-010272/
Thanks
Mark-FMH
Put the stock airbox and air cleaner back on and if u have hoses out of the breather bolts don’t route them to the back of the air cleaner just leave them pointing down or to the side the outer cover will contain the
I have a 2000 Heritage that has been upgraded with a Mikuni carb. I thought it was leaking oil from air cleaner but i just installed a new k&n and come to find out its gas leaking from air cleaner. I thought of the float but it does it only while riding and not all of the time. Help please
It may be leaking from the accelerator pump. Inspect the carb while you twist the throttle a few times. See if you notice any gas.
Verify that your float height is correct and don’t forget to inspect your fuel lines & fittings.
http://www.fixmyhog.com/posts/harley-tips/ (ZD: 3824)
Ok, I am experiencing the same exact problem with my 2009 Ultra. I have changed the air filter but the oil continues to seep out in small quantities. Any other suggestions? Could it be related to a stage one or two upgrade. Thank you.
Will it hurt the engine?
Hi Scott. We are not sure what you are referring to.
I have a 1990 FLHTP with a 2000 rebuilt 1340. Its blowing oil Thur the vent tube. Any ideals?
Hi Bill. You have a bottom breathing motor.
It is normal to have a mist of oil from your bottom breather hose.
If the oil is constant and excessive try stretching your check ball spring in your oil pump.
http://www.fixmyhog.com/posts/harley-tips/
How do I get the screw cap off?
Hi, Bill. Please see your Email for more information!
I have a 2012 Streetglide with a 103 the only thing added from stock is a set of Vance&Hines Hi-out put slip ins I purchased a breather from a newer 103 the scoop looking one it looks like it will take in more air will this require it to be re mapped.
I’m experiencing a similar problem ten fold. I ride a 01 Electra with a twin 88 with a SE rebreather. We were on our way back from a 3 hr ride going 75 on a 95 degree day. Oil started pouring out of my air filter and blown down the bike. Trying to figure out what the deal is. I’m thinking possibly rings are shot or something in the rebreather system. Any thoughts?
Hi Erik. Has nothing to do with piston rings.
This is not completely uncommon with early Twin Cams.
Make sure you are not over filling your oil.
http://www.fixmyhog.com/posts/harley-tips/
oil is poreing out of air breather. with the filter on or off.
Hi Ken. Can we get the year and model.
I recently changed the screen in my tank for my 02 Dyna. After putting it all back together my bike started running rough and now a gas oil mix is pouring out of the breather tube above the carb. I recently had the tank painted due to a fender bender when I pulled the old screen there were paint chips on the screen. What could cause a major flow of gas oil mix to be pouring out of the breather tube and making the bike run and smoke horribly
Hi, Robert. What you are describing is most likely an issue with your fuel pump assembly. Suggest getting back inside fuel tank. Can try a fuel pressure test. Suspect pressure to be low. https://www.fixmyhog.com/video/using-a-harley-fuel-pressure-tester-008741/
I was told a long time ago that when that happened i.e. Was time for an oil change. Is that not true or was someone pulling my leg?
Hi, Mike. No, that has nothing to do with the age or condition of your motor oil. Most typically, when oil is dripping from your air cleaner, the air cleaner element needs to be serviced or replaced.
https://www.fixmyhog.com/video/twin-cam-103-harley-davidson-air-filter-element-service-009155/
I have a ’92 LowRider with low mileage and a similar problem. If I take it out for a spin every week or two there’s no problem. But, if I let it sit for a month or so, the breather tube that plugs into the air cleaner spits oil into the air cleaner. If I unplug the breather tube and look, oil is spiting out (as if the pump is partially pumping). It continues for a few minutes and then stops (maybe a pint or so of oil total).
I’d appreciate hearing your thoughts.
Frank
https://www.fixmyhog.com/post/winter-storage-problem-92-heritage/
Thanks much for pointing me in the right direction
oil from engine breath go to the oil filter how to brevent this
We would be happy to assist you; we just need some more information. What is the make/model/year of your motorcycle?
I have a 2016 wide glide. I purchased it 5 months ago and it’s leaking oil in the same fashion. So I took it to the dealership and they gave me a new filter. I rode it respectfully for 500 miles over the next 2 months and it’s leaking again. I love Harley’s but this is rediculous. I shouldn’t have to be cleaning oil out of an air filter every few months on a brand new bike. Perhaps Harley Davidson should reengineer this part of the bike. Sometimes I think maybe it’s a conspiracy to get us to spend more money on an already outrageously priced machine. BUT. I love my bike!
I have 2015 harleydavidson I have replaced air cleaner notice breather bolts has lot oil comes out on the filter I have a joker air filter what causes this thanks
Hi, Nicholas. The oil from your breather bolts is completely normal. It can, however, be excessive if your engine oil is over-full. https://www.fixmyhog.com/videos/touring-maintenance/
I have 2015 sportster I get oil in my air filter
Hi, Nicholas. All top breathing Harley air filters collect oil that releases as a mist from the top breathers. They require regular service.
Some Harleys will tend to breath heavier than others. If your oil is overfilled, it may breath excessively.
https://www.fixmyhog.com/video/twin-cam-103-harley-davidson-air-filter-element-service-009155/
If I buy Vance hine fuel pack Will that help to stop oil leak in my air filter
whats up fellas, I just got my first bike, what I thought was a steal, its a 95 FXSTS 1340 ,according to the odometer it has 10K miles on it… I was told it had a larger cam installed at some point, has a “butterfly” style air cleaner on it, I could see the filter which looked dirty, I opened it up and noticed oil laying inside the filter housing, and the filter appears to have oil in/on it…ive read some of the post on here and it seems to be somewhat common, but a lot of the posts I have seen are newer bikes so I was just curious about my bike
Hi, Greg. 1995 FXSTS is a favorite of ours. Bob’s main ride. Your motor should be bottom breathing, so excessive oil in your air cleaner element should not be common place. However, the previous owner could have sprayed the element with air filter oil; or the filter may simply be overdue to be cleaned or replaced. Suggest cleaning the filter thoroughly and monitoring from there. https://www.fixmyhog.com/post/videos-harley/
appreciate the info…ill give it a shot
i have a 1991 ultra glide does this air cleaner need the hollow mounting bolts or are they regular bolts?
Hi Tim. If your motor is stock; you have a bottom breathing motor.
You should have regular bolts, not breather bolts, going into your heads.
https://www.fixmyhog.com/post/videos-harley/
i have a 1991 ultra glide can you tell me if the air cleaner mounting bolts are hollow for venting or are they solid?
The stock motor for your year and model is a bottom breathing motor.
The bolts you are referring to should be standard / regulator bolts. Not breather bolts.
I have a 06 Heritage classic which from day one had a S & S air cleaner installed. Problem has been excessive oil dripping out the air cleaner onto the cam cover. Local shop says and I quote “just put the stock air cleaner back on, it’s because your S & S is open backed. Hmmmm no one else with open backed air cleaner covers has this problem. Your thoughts please
Hi, Sandy. If excessive oil is coming out of your breathers, it is due to blow by. http://www.motorcyclecruiser.com/understanding-blowby-motorcycle-engines. Try Googling Harley Davidson blow by for a better understanding. Some bikes are worse than others. Make sure your engine oil is not overfull. It is acceptable to run 1/4 to 1/2 quart low if it helps. If it does not help matters, then don’t. https://www.fixmyhog.com/post/videos-harley/
i have a HD 91 ultra classic, evo engine, when it sits for a month, and I start it up. it blows oil out of the oil breather.. any idea why ? what can be done to fix it. thanks in advance .
Hi Rodger. Some more info here: https://www.fixmyhog.com/post/tag/sump/
My sportster forty eight is having issues finding neutral while running… Also noticed some oil leaking by the intake???
Hey guys, I am changing oil in 2013 Road Glide and noticed a threaded hole on the bottom of the cam case. Like 3/8″ back from the cover. There is no bolt in the hole. And a lot of oil around this area. Is there supposed to be a bolt /machine screw in this hole?
I have a 2003 hd night train with the 88 motor. It is carbed. My bike was just serviced a month ago but yesterday I noticed oil coming from the air filter. By the end of the day I had no oil and my check engine light came on. I checked the codes and they’re all clear. It’s almost like the oil and gas are mixing and causing it to flood. Any idea what could cause this? Also I have a hyper charger air filter on the bike.
You may have a bad oil pump.
Suggest removing your cam cover and cam plate to inspect & diagnose.
https://www.fixmyhog.com/video/harley-davidson-twin-cam-oil-pump-installation-003493/
https://www.fixmyhog.com/video/harley-davidson-oil-pump-service-003482/
https://www.fixmyhog.com/video/how-to-remove-harley-oil-pump-003268/
I have a 2005 Fatboy (w/95 inch kit installed) with about 48,000 miles on it.
I was out for a ride last summer and oil started flowing out of my air intake.
I have had one dealership tell me I need a new engine.
I had another tell me I need new piston rings.
And I had one tell me I need a new oil pump.
Mind you none of them took it in and diagnosed it.
The bike was still on the trailer when they told me.
How do I figure this out.
I had a friend tell me to check the plugs, if they are oily then it’s the piston rings.
If they are clean its probably the oil pump.
any suggestions.
Here is a great article that will give you some better insight on your T/C motor.
After you read it, the first thing you will want to do is check your oil level to be sure you are not overfull.
http://www.motorcyclecruiser.com/understanding-blowby-in-motorcycle-engines
http://www.motorcyclecruiser.com/understanding-blowby-in-motorcycle-engines
my trunk lock broke and fell into trunk and i’m trying to open it any help would appreciated
ok so i have a 99 fatboy 1340 evo 44,000 just got it seems to run like a beast previous owner said he rebuilt the top end ok well prob im havin is smoking ive checked and cleaned my tappet found a tiny bit of metal . went on a 700 mile run recentlly and she started smoking could oit b my spring in my oil pump or is it my valve guide seals. the oil is not over filled. even running open no filter or anything carb ajustment?
Hi Brian. If your motor is smoking, oil is getting by your valve seals – piston rings, or both.
You will not be able to determine which until you disassemble top end.
You will be addressing both at that point, regardless.
You should not have any metal in your tappet screen.
https://www.fixmyhog.com/video/circuits-002183/
How can I get replacement 2 black hoses(2) on air filter 2007 ultra
I just installed a new air filter, for the first time since I bought my bike last August. The bike only has 4000 miles on it, and the air cleaner was more dirty than I expected. It also had some oil on the back of the filter, and not being very mechanical, I wondered if I was disposed to put some oil in or on the new filter, (like a lawnmower)? I know that sounds pretty dumb, but I haven’t had a bike in over 25 years. So even though I’m pretty old, 64, and disabled, so I cannot hold up an 800+lb bike any longer. That’ why I went to a trike. I’m also new, to newer motors…
Breather baffles in rockers may need changed out if oilin up quick after cleaning
My 2017 FLHX is having a blowby problem from the air cleaner. Is this common on the milwaukee 8 and is there a fix?
Hey guys I’m stumped I got an 01 soft tail classic. I have oil spraying from my air filter. I changed the oil 3 weeks ago about 1000 miles and it ran great until this morning. Oil was filled and checked while hot. I have a k&n air filter and just replaced it, I tried to run my bike with the oil level at the bottom add line and it still dumped 1/2 a quart on a 30 mile ride home from work. All my hoses are clear and the oil is diffinatly coming from the rear breather tube. I’m thinking about replacing my breather assembly on my rocker arm assembly but was wondering if that was a good way to go. Any help would be appreciated
Hi Isaiah. Yes, you may end up having to inspect/service/replace your breather assemblies if the problem persists.
Obviously, make sure that your oil is not overfull.
https://www.fixmyhog.com/video/drain-fluids-001250/
You could be dealing with a condition called blow-by. Here is an article that explains.
http://www.motorcyclecruiser.com/understanding-blowby-in-motorcycle-engines
Thanks
Mark-FMH
I have a 1991 Harley Davidson ultra classic. When the bike gets to normal operating temperatures it shots oil from the crankcase tube thru the carb. When first notices the whole side of the bike was covered with oil. It is not a mist, with air cleaner off it will shot 2feet from the bike till shut bike off. Do you think this is a bad check valve or do you think it is something else. Thank you for any help
after having my bike service 400 miles it start doing it again
My air filter has less than 1200 miles on. Installed a new one on last oil change. Noticed some leakage today. 12/6/17
I’ve got a 2006 Harley Softail Deluxe. It had never drip oil ever. Then two weeks ago I rode about 80 miles though what was basically a sandstorm with wind about 50 miles per hour, kicking up sand and tumbleweed and all sorts of crap. On my way home the following day, it was a calm day with zero wind. After about 40 miles the oil light began flickering.
I pull over to a gas station. I noticed I was way way low on oil. In fact, it was undetectable. Since the gas station had no motorcycle oil the dealership I called told be that in an emergency I could you diesel oil until I got home then change oil.
So I added two quarts of diesel oil. I rode about a quarter mile when I notice a steady flow of oil was pouring out from the air cleaner. I turn my harley off and then trailer it home.
I am the least mechanically inclined harley owner you’ll ever meet. Any ideas what the problem might be?
Unfortunately, from what you describe; sounds like you may have a broken oil pump.
We would suggest inspecting the oil pump and your top end.
https://www.fixmyhog.com/video/harley-davidson-twin-cam-oil-pump-installation-003493/
https://www.fixmyhog.com/video/harley-top-end-removal-008743/
https://www.fixmyhog.com/video/how-to-remove-harley-oil-pump-003268/
https://www.fixmyhog.com/video/hydraulic-harley-cam-plate-oil-pump-and-chain-tensioner-shoe-upgrade-003488/
Hey guys, looking for some help here.
I have a 2003 Sportster XL Custom which has been running great up until a week ago when it started showing lean symptoms. I replaced my carburetor seal to the intake manifold and it seemed to run much better. Ran great for a week and then it started bogging out, hesitating and I figured it was the same issue (maybe the intake manifold seals that connect to the engine cylinders) but when I went to take my air filter off I noticed a squirt of oil had come out of the breather bolt which has not happened in the past. During this whole process I DID have my oil tank overfilled unfortunately, to the top line on the dip stick ( my buddy told me that it didnt matter if it was overfilled and Im a rookie.. now i realize it does matter)
I am wondering if by overfilling my oil tank, I have over pressurized my crank case and fucked all my seals. Bike will not start now unless fully choked and even then it idles too high and bogs out. Pretty bummed and would appreciate any advice.
If you compromised any of your motor gaskets, you would know because they would have started leaking.
We suggest replacing intake seals and giving your carb a thourough cleaning/inspection. Sounds like you may have a blocked intermediate (slow) jet. Replace spark plugs.
And definitely, set correct oil level.
Check your oil, level, on the kickstand.
https://www.fixmyhog.com/videos/carburetor-rebuild/
https://www.fixmyhog.com/video/harley-carburetor-rebuild-007192/
https://www.fixmyhog.com/video/twin-cam-harley-intake-seals-replacement-008713/
https://www.fixmyhog.com/videos/sportster-maintenance/
-Mark
Q: I just built a 05′ CVO Ultra Classic,
Bottom end done by Dark Horse, S&S Gear drives, T-3 cam plate and oil pump, S&S .585 cams, 10.25:1 dome top pistons
.010 on the cylinders, heads completely reworked.
The problem I’m having is a lot of oil blow by from the head breather vents, so much so I had to put a catch can to catch
the oil so it doesn’t go all over.
Last week the bike owner rode the bike approx. 200 miles with so much oil blow by it filled the catch can (approx. 2 cups)
and then blew out the can over flow! Oil has never been overfilled in fact maybe a little under!
Any Thoughts!
A: That is blow by.
Would suggest plumbing the top breather to the ground. Away from the rear wheel. Otherwise, you will have to get back into this motor in order to diagnose & correct.
On blow by article. Had 28k on 08 ultra stock 96ci. Rings stuck to pistons ruined cylinders. Never had any oil loss in 5k miles not even an aircleaner wet. Under warranty they bored cylinders, new pistons and rings, but never relapped valves or new seals in heads. Ever since rebuild if i run at 3000 rpm on interstate for long rides i smell oil burning and oil at bottom of aircleaner. Have complained to dealer they say normal and harley wouldnt authorize head work cause not enough miles and not damaged. Come even a good car mechanic would have replaced the seals on the valves. I do, seals are cheap and not that labor intense. Any ideas or did i get screwed by the Big Corp. and end up with an oil sucker in 1500 miles / 1 qt. On interstate 75-80mph and 1qt / 3000 2200 – 2500 rpm highway at 60mph. Ideas?
Possible that the cylinders were not correctly machined/sized or the rings did not correctly seat. Unfortunately, to achieve an accurate diagnosis you will need to disassemble your top end.
https://www.fixmyhog.com/post/videos-harley/
-Mark
Same problem on my ’17 Ultra Classic. (2,500 miles) 1/2 quart of oil gone between 1,000 mile oil change and 2,500 miles. Dealership broke it down found front cylinder scoring and rear cylinder valve seals leaking. Between the score marks he could still see the cross hatching from the factory boring. Technician said he’d never seen anything like it. Waiting on parts now, missing my girl.
If you have a newer bike the umbrellas in the head need to be replaced.They control the breathing of the crankcase.It’s not going to be the breather element or the rings.I’ve replaced these twice in my own bike in the last 15 years.It is a bad design because all the rules for poulution.I redesigned the ports coming out of the heads eventually,I’ll try to attach a pic to give you the idea I did
Ticket 18342 My 2013 Street Glide is dripping oil from the breather. I have the cleaned the breather. I let the bike run just for a little bit to see if it was still leaking. On the back plate I have to holes that oil is still leaking from. Is that normal or not.
Dear Aj,
Thank you for your patience. In regards to your question-
Some motors will breath heavier than others. Make sure that your air cleaner assembly is installed correctly and that the air cleaner element is clean.
Suggest a K&N element of you do not already have.
https://www.fixmyhog.com/video/how-to-search-fix-my-hog-008641/
We’d love to have you be a part of our community. We are convinced you will enjoy the benefits of becoming a member and having access to the best instructional how to videos and professional tips. We would like to offer you a special promotion for your first-year membership.
https://go.fixmyhog.com/C13249
Sincerely,
Mark
Fix My Hog Video Membership
Regarding 1989 electraglide. Owing to personal circumstance my hog has being idle for quite a time. There is spark at plugs but oil spurting into air cleaner, and almost peeing out. When cranking. Battery is new so will turn over but not fire up. What is the issue and how to fix please
Dear David,
Thank you for your patience. In response to your question-
Older Evolution models will sump oil into the bottom of the crankcase when they sit for long periods of time. That is common.
You can remove the bottom breather hose from the air cleaner backing plate and route it down to a container until the bike is finnished sumping.
If you have spark, you must have bad fuel or contaminated fuel system. We highly recommend draining out all old fuel.
Clean and rebuild carburetor uf nessacary. Also replace intake seals and flanges.
https://www.fixmyhog.com/video/how-to-search-fix-my-hog-008641/
https://www.fixmyhog.com/video/welcome-to-fix-my-hog-site-review-008131/
https://www.fixmyhog.com/video-index/
We’d love to have you be a part of our community. We are convinced you will enjoy the benefits of becoming a member and having access to the best instructional how to videos and professional tips. We would like to offer you a special promotion for your first-year membership.
https://go.fixmyhog.com/c16259
Sincerely,
Mark
Fix My Hog
Thanks for your time, and all of your knowledge, this help me, Thanks
my 13 road glide blows oil out air cleaner.engine rebuilt to 117-120.is it just to much compression.or could rocker box vents be installed wrong.
GREAT write up! I have a question about my Shovelhead.
1979 Electra Glide FLH 1200 King of the Highway full dresser.
First off, NO she does NOT leak! She doesn’t “mark her spot”. I hate that.
I found her December 2017. Sitting in a little Independent bike shop for sale. Previous owner had her 27-years.
Lately I’ve noticed a very light mist of oil on the front face of the chrome battery cover. I’ve checked and tightened everything. Tappet blocks, all oil lines, rocker boxes, everything! The bike starts, idles and runs VERY
well and is a blast to ride!
In 2002 the previous owner upgraded the engine and transmission with all new bearings. The 4-speed is solid. All OEM with 3.00 first gear and shifts perfect.
The 74″ FLH 1200 engine received +0.020″ forged pistons, S&S Super Stock
single plug heads, Super E carburator, Head Quarters Torquer cam @ 0.465″
lift, Jim’s Powerglide Tappets & pushrods, Alto clutch, true dual exhaust.
All I had to do was new tires. Mounted Metzler ME888 Ultra Marathon Wide White Walls. The spoke rims are true straight.
The Super E carburator runs a”dry” filter and in new this riding season.
For the life of me I cannot figure out WHERE this oil mist is coming from!
Thanks. Keep up the good work!
Brian
Forgot…..the forged +0.020″ pistons are 10:1 compression.
I think I might have found it. Just for grins I ran a finger around the
inner side of the S&S Teardrop air cleaner cover and found a
small amount of oil. Removed and cleaned. OK for now.
I have a 1989 soft tail, I also have oil POURING out of my crank case venting filter, what’s up with that?
Frederick,
Oil sumping is common on bottom breathing motors after a prolonged storage or after over filling the motor oil.
If, however, you have an on going sumping issue, you will likely need to replace your oil pump. We suggest S&S billet oil pump or Jims.
https://www.fixmyhog.com/post/in-the-shop-evolution-oil-pump/
How do I fix oil dripping from the crankcase breather filter on my 90 FXRS-SP?
Chet,
You can try removing the oil pump check valve ball & spring.
Clean the bearing and the oil pump bore, then stretch the spring about 1/4″ longer.
Use a drag link or a chisel to unscrew the cap of the taller tower on the oil pump to access.
If the bike continues to sump, you will likely need to replace your oil pump.
https://www.fixmyhog.com/post/in-the-shop-evolution-oil-pump/
-Mark
Fix My Hog
I solved the problem of oil dripping through oil filter, took off rocker covers and removed umbrella valve then drill out oil return hole, dont remember the size drill use, but it can be found online, then I put in new umbrella valve, I also got a drag specially bango bolt kit with bolts for the breather holes in the head, it came with tubing and a filter, installed the kit, then I modified the backing plate so no lines going to filter and ran both breather tubes to supplied filter, wa la no more oil going back to engine, the hell with EPA, putting oil back to the intake is bad creates carbon build up on your pistons
I recently experienced this problem on my 2018 Street Glide. I. recently performed the stage 1 upgrades