oil in airbox

[Jharpphoto]

after a recent 18,000 mile service on my 2013 RT, I started smelling burning oil. Prior to this service I didn’t have any odor of burning oil whatsoever. I took the bike back after 500 miles to have the tech look at the bike and see if he could find any leaks or drips that I could not find. the tech suggested a further inspection, removing the panels and looking in the airbox. Upon further examination, the tech found oil in the airbox and excessive carbon buildup which he says, is causing a piston seal failure, which is allowing oil to enter the airbox thereby causing the burning oil odor.  I’m a little confused at this development and carbon buildup. The tech suggest that this could be caused by using bad gas, which is unusual, because I’ve only put supreme 93 octane gas in the vehicle. He’s doing a cleaning ,removing some carbon, hoping that allows the pistons to seal properly . The tech also said if this doesn’t work, he will have to get into the engine do pistons and a number of other very expensive repairs. My question is, does this sound like a legitimate series of issues? I did tip the bike over once after the service I’m curious if oil might have gotten into the airbox when the bike tipped over.  not looking forward to spending thousands on having the piston rings done etc. any suggestions? 

[dirtrider]

18 minutes ago, Jharpphoto said:

after a recent 18,000 mile service on my 2013 RT, I started smelling burning oil. Prior to this service I didn’t have any odor of burning oil whatsoever. I took the bike back after 500 miles to have the tech look at the bike and see if he could find any leaks or drips that I could not find. the tech suggested a further inspection, removing the panels and looking in the airbox. Upon further examination, the tech found oil in the airbox and excessive carbon buildup which he says, is causing a piston seal failure, which is allowing oil to enter the airbox thereby causing the burning oil odor.  I’m a little confused at this development and carbon buildup. The tech suggest that this could be caused by using bad gas, which is unusual, because I’ve only put supreme 93 octane gas in the vehicle. He’s doing a cleaning ,removing some carbon, hoping that allows the pistons to seal properly . The tech also said if this doesn’t work, he will have to get into the engine do pistons and a number of other very expensive repairs. My question is, does this sound like a legitimate series of issues? I did tip the bike over once after the service I’m curious if oil might have gotten into the airbox when the bike tipped over.  not looking forward to spending thousands on having the piston rings done etc. any suggestions? 

Afternoon Jharpphoto

 

I hope that you had your boots on when that tech was talking!

 

Some of what he said is true but not much.

 

For starters what are piston seals? If that is in reference to the piston rings, it would be odd that carbon buildup effected their sealing.  But even if excessive carbon effected the piston ring sealing it is the oil ring (lowest ring on the piston) that would allow excess oil past.

 

To start with, a little oil in the air box is normal, the problem is if it is excessive or not. If the motorcycle was ever tipped over on it's side with the engine running that can quickly add oil to the air box.  

 

If the oil level in the crankcase is over-full that can also add some oil to the air box through the crankcase vent system.

 

Is the oil in the air box even where your oil smell is coming from? Unless very high, or a large amount, then the oil usually just sits in the bottom not causing any smell or any other problems.  

 

On the BMW 1200 engines the usual cause of an oil burning smell with no real signs of oil leakage is a slight seep at the rear engine balance shaft. Just enough oil seeps past to end up on the front of the catalytic converter where it burns off leaving a slight oil burning smell. (is the front of your catalytic converter dark or look like oil spots that have burnt off & left spots or streaks?)  

 

 

[Jharpphoto]

6 minutes ago, dirtrider said:

Afternoon Jharpphoto

 

I hope that you had your boots on when that tech was talking!

 

Some of what he said is true but not much.

 

For starters what are piston seals? If that is in reference to the piston rings, it would be odd that carbon buildup effected their sealing.  But even if excessive carbon effected the piston ring sealing it is the oil ring (lowest ring on the piston) that would allow excess oil past.

 

To start with, a little oil in the air box is normal, the problem is if it is excessive or not. If the motorcycle was ever tipped over on it's side with the engine running that can quickly add oil to the air box.  

 

If the oil level in the crankcase is over-full that can also add some oil to the air box.

 

Is the oil in the air box even where your oil smell is coming from? Unless very high, or a large amount, then the oil usually just sits in the bottom not causing any smell or any other problems.  

 

 

thanks so much for your reply. It is likely I misquoted the tech. He probably was referencing the piston rings. I did tip the bike over which could cause the oil in the airbox. I guess I am most concerned with the comment about excessive carbon build up. I typically ride in the 4500 RPM range soo I don’t believe low rpms are causing the carbon. 

[dirtrider]

4 minutes ago, Jharpphoto said:

thanks so much for your reply. It is likely I misquoted the tech. He probably was referencing the piston rings. I did tip the bike over which could cause the oil in the airbox. I guess I am most concerned with the comment about excessive carbon build up. I typically ride in the 4500 RPM range soo I don’t believe low rpms are causing the carbon. 

Afternoon Jharpphoto

 

Does that motorcycle use any oil? Do you have to add any oil between oil changes?

 

On the BMW 1200 engine excessive carbon usually comes from some oil burning when new, most eventually fully break in so the oil burning stops but  that carbon can remain for life if it is hard carbon. 

[Jharpphoto]

my bike does require topping off between changes.

[Jharpphoto]

hoping my bike “settles in” and stops burning oil soon. I’m at 18k miles so certainly I should be close

[dirtrider]

3 minutes ago, Jharpphoto said:

my bike does require topping off between changes.

Afternoon Jharpphoto

 

Then that is probably where your carbon is coming from. 

 

 

[Jharpphoto]

 

Here is the diagnosis from the BMW tech.  REAAALLY hoping his prescribed course of action takes care of the issue. The service writer suggested I "ride it like I stole it, at VERY high RPMS for 150 miles".  

[Jharpphoto]

CRAP!!!!!  Just returned from running a tank of fuel through the bike at highway speed/high RPMS.  This was the recommended procedure per the BMW mechanic.  Upon pulling into my garage the low engine oil light came on. Oil is 2/3 down the sight glass. The mechanic said he topped off the oil in his notes.  I immediately called the service manager to let them know what I experienced and was told the last thing I wanted to hear.  The bike is going to need a major compression diagnostic and repair aka LOTS OF MONEY! @dirtrider is there any circumstance where this isn't going to cost me thousands to repair?

 

[TSConver]

Sounds like it needs new rings.

[Jharpphoto]

I’m afraid you are right. That sounds expensive

[dirtrider]

34 minutes ago, Jharpphoto said:

CRAP!!!!!  Just returned from running a tank of fuel through the bike at highway speed/high RPMS.  This was the recommended procedure per the BMW mechanic.  Upon pulling into my garage the low engine oil light came on. Oil is 2/3 down the sight glass. The mechanic said he topped off the oil in his notes.  I immediately called the service manager to let them know what I experienced and was told the last thing I wanted to hear.  The bike is going to need a major compression diagnostic and repair aka LOTS OF MONEY! @dirtrider is there any circumstance where this isn't going to cost me thousands to repair?

 

Afternoon Jharpphoto

 

There are some circumstances that could apply that might be an easier fix. An oil usage situation takes a lot of hands-on testing to be somewhat confident that the problems root cause is identified & found. This is very difficult to do over the internet. 

 

The low engine oil light coming on at  2/3 down the sight glass is typically not low enough to light the low oil light. Where is the oil level after the motorcycle sits overnight?

 

If it (IS) a piston ring to cylinder sealing issue, on the BMW 1200 engines that usually isn't a piston ring problem it is usually a glazed cylinder wall problem causing the rings to not seal properly to the exceptionally smooth cylinder walls. 

 

If it was me working on that motorcycle I would probably re-check the bottom of the air filter box  to see if it is full of oil again after your spirited ride. If there is a puddle of oil in the air box again then that will tell us something. 

 

I would probably also run a cylinder leak-down test to see if that points to a side or points to something. 

 

With oil caking on the back side of the valves that can also point to a leaking or missing valve seal allowing oil to migrate down the valve stems. 

 

I would also verify the crankcase vent impeller is there & working properly.  

 

What oil brand & viscosity are you using? Sometimes changing oil brands & going to the highest viscosity oil that BMW allows can reduce oil usage (usually won't completely eliminate it but sometimes can help) 

 

 

 

 

 

 

 

 

 

[Jharpphoto]

13 minutes ago, dirtrider said:

Afternoon Jharpphoto

 

There are some circumstances that could apply that might be an easier fix. An oil usage situation takes a lot of hands-on testing to be somewhat confident that the problems root cause is identified & found. This is very difficult to do over the internet. 

 

The low engine oil light coming on at  2/3 down the sight glass is typically not low enough to light the low oil light. Where is the oil level after the motorcycle sits overnight?

 

If it (IS) a piston ring to cylinder sealing issue, on the BMW 1200 engines that usually isn't a piston ring problem it is usually a glazed cylinder wall problem causing the rings to not seal properly to the exceptionally smooth cylinder walls. 

 

If it was me working on that motorcycle I would probably re-check the bottom of the air filter box  to see if it is full of oil again after your spirited ride. If there is a puddle of oil in the air box again then that will tell us something. 

 

I would probably also run a cylinder leak-down test to see if that points to a side or points to something. 

 

With oil caking on the back side of the valves that can also point to a leaking or missing valve seal allowing oil to migrate down the valve stems. 

 

I would also verify the crankcase vent impeller is there & working properly.  

 

What oil brand & viscosity are you using? Sometimes changing oil brands & going to the highest viscosity oil that BMW allows can reduce oil usage (usually won't completely eliminate it but sometimes can help) 

 

 

 

 

 

 

 

 

 

@dirtriderthanks for your reply. It sounds like there is a lot of testing in my future. I'll check the oil level in the AM but that the low oil indicator came on certainly isn't a good sign, I'm sure.   If there was oil in the air box again after my ride what would that indicate?  I use 20W-50 weight oil by Liqui Moly.  I have no real recourse other than to take it back to the shop next week for extensive testing I guess.  I'm definitely pretty disappointed with these issues but hopefully will get some resolution after new evaluation from the BMW tech. 

[Jharpphoto]

@dirtrider I am blown away and not in a good way.  I just spoke with the service adviser after the shop did a compression test and leak down test.  The tech has recommended replacing piston rings and valve seals as well as cleaning the top end. to the tune of $3,200 freaking dollars.  I mentioned earlier in my post that I had no issues until this shop conducted the 18K mi service on my bike. After that service I started smelling burning oil.  I feel like I'm getting screwed here.  I've bought multiple bikes from this shop and have had good service til now.  Does this sound like a reasonable amount for this service?  I don't know but something doesn't feel right about this. Not to mention, I just paid the bike off in December.

[Dave_in_TX]

8 minutes ago, Jharpphoto said:

@dirtrider I am blown away and not in a good way.  I just spoke with the service adviser after the shop did a compression test and leak down test.  The tech has recommended replacing piston rings and valve seals as well as cleaning the top end. to the tune of $3,200 freaking dollars.  I mentioned earlier in my post that I had no issues until this shop conducted the 18K mi service on my bike. After that service I started smelling burning oil.  I feel like I'm getting screwed here.  I've bought multiple bikes from this shop and have had good service til now.  Does this sound like a reasonable amount for this service?  I don't know but something doesn't feel right about this. Not to mention, I just paid the bike off in December.

It's hard to imagine that they could have done something at the 18k service that would cause this problem. Did they adjust valves? Usually, valves aren't checked at 18k and the most major thing is an oil change.

 

If the cylinder walls are glazed (which DR mentioned as a possibility) , new rings won't fix the problem. I don't know if those cylinders can be honed which is the usual way to remove glazing.

[dirtrider]

18 minutes ago, Jharpphoto said:

@dirtrider I am blown away and not in a good way.  I just spoke with the service adviser after the shop did a compression test and leak down test.  The tech has recommended replacing piston rings and valve seals as well as cleaning the top end. to the tune of $3,200 freaking dollars.  I mentioned earlier in my post that I had no issues until this shop conducted the 18K mi service on my bike. After that service I started smelling burning oil.  I feel like I'm getting screwed here.  I've bought multiple bikes from this shop and have had good service til now.  Does this sound like a reasonable amount for this service?  I don't know but something doesn't feel right about this. Not to mention, I just paid the bike off in December.

Evening  Jharpphoto

 

I kind of smell a rat here, but not doing the tests myself there is no good way to tell you anything conclusive. 

 

The valve seals (usually just 1 or 2) would be a possibility though. 

 

But as you say, if it didn't start until after the service then I seriously doubt the valve seals or the piston rings suddenly failed just after that service. 

[Jharpphoto]

I just got off the phone w/ the dealership owner.  He told me there was nothing done at the 18k service that would have been a catalyst for the burning oil smell or oil in the airbox. He said unfortunately, it was most likely an unfortunate coincidence. I'm so aggravated and don't really know what to do here.  I guess I could have the bike trailered to another shop for a second opinion.

[dirtrider]

22 minutes ago, Jharpphoto said:

I just got off the phone w/ the dealership owner.  He told me there was nothing done at the 18k service that would have been a catalyst for the burning oil smell or oil in the airbox. He said unfortunately, it was most likely an unfortunate coincidence. I'm so aggravated and don't really know what to do here.  I guess I could have the bike trailered to another shop for a second opinion.

Evening  Jharpphoto

 

I have a very difficult time buying that unfortunate coincidence excuse. It's slightly possibly but probably not likely. 

 

It could be a related deal such as they put an oil in that is more prone to getting past the rings. 

 

I don't have a lot of advise for you as I haven't worked on that motorcycle myself so all we REALLY know is that it has an oil-in-the-airbox issue &  what the dealer is saying.

 

I think I would first try a different oil brand with the heaviest viscosity that your riders manual say is OK for your riding temperatures. 

 

Then ride it a while to see if that helps.

 

If that doesn't make a difference then I would definitely recommend getting an opinion from a different shop. 

 

If you do get it repaired then probably start with the valve seals first, but typically a bad valve seal (or seals) causes oil burning & smoke at cold start-up but not that oil in the air box. 

 

That oil in the air box is usually due to too much crankcase pressure, or a crankcase venting problem, or over-filled oil level. Some of this could be from leaking piston rings & a good quality leak-down test should show that. The thing is, DID that dealer due a good quality leak-down test or just guess at it?   

 

Added: I do have another sort-of thought__ Is there any chance that your exhaust flapper valve is stuck closed or partially closed? If so that can cause a lot of exhaust back pressure that can in a round-about way increase crankcase pressure.  

 

 

[Skywagon]

Can you ask them for the numbers on the compression test and the leak down test and post back here for DR to weigh in?

[Jharpphoto]

results of the compression test=

left cylinder        right cylinder

293 PSI               248 psi

 

results of the leak down test=

left                 right

13%                16%

 

tech said there was oil gurgling near oil fill plug.

[dirtrider]

14 hours ago, Jharpphoto said:

results of the compression test=

left cylinder        right cylinder

293 PSI               248 psi

 

results of the leak down test=

left                 right

13%                16%

 

tech said there was oil gurgling near oil fill plug.

Evening  Jharpphoto

 

Not knowing exactly how the testing was done, or the calibration on the test equipment then it is difficult to tell anything conclusive from those numbers.  

 

Was the compression & leak-down done on a warm engine? (this can make a significant difference)

 

The L/H side compression is significantly higher than the right , but why? Is it due to that side being the oil burner side so that side has a lot of carbon buildup that increases compression, or possibly a lower spark plug was left connected & that side fired during the testing, or is it due to the slightly higher leak-down on the R/H side therefore lowering the R/H side?   

 

The leak-down is a bit on the high side but I have seen higher than that with little or no oil burning or  excess crankcase pressure, if it was done cold then it might not even be that bad. 

 

To me, unless it has very high leak-down numbers, then WHERE the leakage is coming from is usually more important than how much it is leaking.   That gurgling at the oil filler is usually not a good sign though as that typically points to a piston ring leakage issue. But if engine was cold during the testing  then possibly not as bad as it sounds.  

 

This is something I usually dig into a little farther before giving any sort of confirmed diagnosis. 

[Jharpphoto]

@dirtrider  I proceeded with the maintenance suggested by the BMW dealership (although with a bit of hate in my heart). Picked up the bike yesterday and didn't have a chance to ask the service manager/tech about the recommended RPM range for break in.  I don't see info in the manual about break in procedure either.  Below are the notes from the tech that conducted the service. 

"Removed cylinders, cleaned cylinders and pistons of carbon. Replaced piston rings both cylinders. Removed all valves from heads. Thoroughly cleaned the carbon buildup from heads and valves. Replaced valve guide seals. Reassembled top end. Set ignition timing. Checked valve clearances. Calibrated idle actuators. Performed throttle body sync. Drained and filled engine oil. Set oil level. test rode. Function tested. Motorcycle runs and rides as designed. Recommend return in 600-1000 miles for visual inspections.  Recommend break in- vary speeds and gears as much as possible. No high revs until 600 miles(what is considered high revs is there a recommended  a rev range to stay within). No lugging in high gears."

 

In looking online there seems to be a wide range of break in suggestions and rpm ranges etc.  I did notice on the short ride home the bike sounded a little different.  Hoping to get out today to start breaking her in.

 

[dirtrider]

30 minutes ago, Jharpphoto said:

@dirtrider  I proceeded with the maintenance suggested by the BMW dealership (although with a bit of hate in my heart). Picked up the bike yesterday and didn't have a chance to ask the service manager/tech about the recommended RPM range for break in.  I don't see info in the manual about break in procedure either.  Below are the notes from the tech that conducted the service. 

"Removed cylinders, cleaned cylinders and pistons of carbon. Replaced piston rings both cylinders. Removed all valves from heads. Thoroughly cleaned the carbon buildup from heads and valves. Replaced valve guide seals. Reassembled top end. Set ignition timing. Checked valve clearances. Calibrated idle actuators. Performed throttle body sync. Drained and filled engine oil. Set oil level. test rode. Function tested. Motorcycle runs and rides as designed. Recommend return in 600-1000 miles for visual inspections.  Recommend break in- vary speeds and gears as much as possible. No high revs until 600 miles(what is considered high revs is there a recommended  a rev range to stay within). No lugging in high gears."

 

In looking online there seems to be a wide range of break in suggestions and rpm ranges etc.  I did notice on the short ride home the bike sounded a little different.  Hoping to get out today to start breaking her in.

 

Afternoon  Jharpphoto

 

There are a LOT of varying opinions on proper BMW boxer engine break-in. 

 

My personal way (I haven't ever ended up with a BMW boxer 1100/1150/1200 burning oil).

 

That is, I do a lot of 1/2 & 3/4 throttle short burst accelerations, a lot of long downhill closed throttle over-run coasting (with some throttle on then back off during the costing), this allows the rings to sort of self clean.  I also continually keep varying the engine RPM's by shifting gears & varying throttle positions.

 

No drone type  freeway riding for at least 1000 miles. I will get on the freeway for short distances but only with varying speeds & changing throttle positions/engine loading.  

 

Lots of engine heating/cool downs cycles during the first 600 miles. 

 

No light-throttle steady state cruising,  keep varying vehicle speed, varying engine RPM's, & varying engine load.

 

Then after 600-700 miles doing the above I start including some short burst wide-open-throttle with short burst closed throttle coasting right after the open throttle runs. 

 

Then once I get to 1000 miles I just ride I like normal from then on but in a lot of cases I will do an oil change at the 1000 mile mark.  

 

One rule of thumb that I use on a newly assembled engine or new engine is to not do anything the same (RPM. engine load, throttle position)  for long periods until at least 600 miles.  

 

 

[Jharpphoto]

great suggestions. Thanks @dirtrider

[Jharpphoto]

@dirtrider one more clarification.  The BMW tech recommends varying gears and rpms. I'm assuming that means some miles in 5th and 6th gear as well?  If so that can really only be done on highway riding.  I see you suggest no highway miles til after 600 miles.  How important is riding the bike in 5th or 6th gear?  Are the rpm ranges more important than the gears used?

[dirtrider]

16 minutes ago, Jharpphoto said:

@dirtrider one more clarification.  The BMW tech recommends varying gears and rpms. I'm assuming that means some miles in 5th and 6th gear as well?  If so that can really only be done on highway riding.  I see you suggest no highway miles til after 600 miles.  How important is riding the bike in 5th or 6th gear?  Are the rpm ranges more important than the gears used?

Afternoon  Jharpphoto

 

That would be good information on a brand new motorcycle with 0 miles on it as you need to keep in mind that you are not only breaking in the engine but also breaking in the final drive gear-set as well as the transmission gear-sets.

 

In your case it is only the engine being broken in so use the gears that you need to get the results you require. In most cases you can get enough engine load in 4th & 5h gears that 6th wouldn't be required. Just keep in mind that lugging an engine during break-in is typically not something that you ever want to do.   

[Jharpphoto]

I'm at 500 miles into the "re-breaking in" of the engine after the major service my bike recently had.  I have been following the advice of @dirtrider to the letter in this process.  The bike seems to be running fine, although I am a little nervous about it's reliability at this point. Ive been checking the oil in the sight glass along the way and until yesterday I hadn't seen any drop in the oil level in the glass.  I commuted on the bike all week and had not checked the oil in 7 days. After a 100 mile ride yesterday, I noticed the oil was a little more than 50% down the sight glass.  I was a little surprised to see that drop in oil level.  I am hoping that with  all the bike has gone through with the ring replacement etc that some oil dissipation is to be expected.  At this point I'm so nervous about every little sound and smell that I don't want to overreact to some oil use after 500 miles of riding.  @dirtrider is the oil use I'm seeing to be expected on a bike that just had replaced piston rings and valve seals as well as cleaning the top end?

[dirtrider]

27 minutes ago, Jharpphoto said:

I'm at 500 miles into the "re-breaking in" of the engine after the major service my bike recently had.  I have been following the advice of @dirtrider to the letter in this process.  The bike seems to be running fine, although I am a little nervous about it's reliability at this point. Ive been checking the oil in the sight glass along the way and until yesterday I hadn't seen any drop in the oil level in the glass.  I commuted on the bike all week and had not checked the oil in 7 days. After a 100 mile ride yesterday, I noticed the oil was a little more than 50% down the sight glass.  I was a little surprised to see that drop in oil level.  I am hoping that with  all the bike has gone through with the ring replacement etc that some oil dissipation is to be expected.  At this point I'm so nervous about every little sound and smell that I don't want to overreact to some oil use after 500 miles of riding.  @dirtrider is the oil use I'm seeing to be expected on a bike that just had replaced piston rings and valve seals as well as cleaning the top end?

Afternoon Jharpphoto

 

A little oil usage in the first 1000 miles is not abnormal but a lot of oil usage is abnormal.

 

Due to the inconsistencies on oil levels in the BMW boxer engines it is advisable to check the oil level  in the very same place (same place & direction in your garage or driveway),  try to check after riding for while (hot engine, thinner oil, expanded crankcase volume). Also try to check after the motorcycle sits on the center stand for the same amount of time. 

 

Possibly after returning home after your commute, put the motorcycle in the same place, put it on the center stand, then check oil level after 20 minutes of sitting. 

 

 

[Jharpphoto]

thanks so much for your insight and suggestions @dirtrider . I'll do just that.  Have a great weekend sir.