Burned Oil Smell

[malcolmblalock]

I have a question that I don't recall having been posted before. I have a 2009 RT with 37K miles on the odometer. It has had regular services performed.

 

I noticed about 1K miles ago that sometimes when I would stop at a stop light or stop sign, that I would smell the aroma of burning oil, like oil smells when it gets on an exhaust manifold in a car. It happens only when the bike if fully warmed up, and seems to be a little more noticeable when I've ridden the bike harder than normal. It's not from another vehicle; it happens when I'm in the middle of nowhere and no vehicles are anywhere near.

 

I've looked all over the sides and bottom of the engine, and everything is 100% dry; no evidence of any leak. Nothing around the transmission either. I mentioned it to the dealer just before 36K miles, but he didn't see anything and acted like I was imagining things.

 

The bike uses almost no oil; I added about 8 ounces over the last 6K miles.

 

Any ideas as to what might be causing the odor?

[dirtrider]

Afternoon siman00

 

Could be about anything from a bit of an oil leak inside the clutch housing, to a crankcase vent line not sealed tight, to a light oil mist ending up on a hot engine part, to some trans fluid seeping onto the cat. converter, to ????.

 

OR, I worked on a similar problem last summer for a friend. He had no noticeable oil leaking or witness strains on the engine & what I eventually found was a front fork seal seeping just enough to blow fork oil back on the exhaust pipes & bring on a burning oil smell.

 

So, look CLOSELY for fork seal seepage, look for any (even very slight) dark staining on the front & top of the cat. converter. Look for oil at the crankcase vent hose, look (carefully) that the oil fill cap is sealing TIGHTLY & the "O" ring is intact. Look for rear shock seeping onto hot exhaust parts.

 

[malcolmblalock]

D.R., thanks for giving me some places to start looking more closely. Where is the crankcase vent line on the engine? I'll look at the clutch housing area carefully. And, I could see no evidence of oil or fluid on or around the transmission, so I don't think it's the tranny. The oil fill plug is tight and not leaking or seeping.

 

Sounds like your main suspicion is the fork seal or the rear shock, so I'll examine them very closely. I'll get back to you when I do my checking. I'm recovering from a cardiac stent installation, so it may be a few days before I can do the checking.

 

Other thoughts, anyone?

[dirtrider]

[malcolmblalock]

Thanks, D.R. I know where to look now.

[ed may]

I am suprised to see this thread, as I too have recently been smelling burning oil. I thought it was another vehicle, but it seems to happen when there are no other vehicles around. I checked the forks, the shocks, and the breather tube. I don't see anything dripping. I do have some very minor oil residue under the clutch slave, and although that is above the exhaust, I don't see evidence of a drip. Being a mechanic, I know it's nearly imposssible to to keep a motor vehicle completely oil seep free. I don't know if it is related, but I changed my oil recently, and it didn't seem to smell before that. I did not spill any oil on anything in the process. Please don't start an oil war here, but I just want to note that I went from Full synthetic Mobil 1 silver cap 15W-50 to Partial Synthetic Castrol Power 1 4T 15W-50. I doubt that has anything to do with it. It is filled just to the top of the sightglass, but not above. It has been 600 miles since the oil change, and I havn't had to add any oil. Earlier, when the motor had 3,000-8,000 miles on it, I did have to add a few ounces every 1k, but that seems to have gone away. I suppose the rings are seating good, so I don't think the smell is coming out of the exhaust. The filter and fill cap are not leaking. I can't figure it out, but also not going to worry too much about it.

[dirtrider]

Evening Ed

 

Look closely up on top of the cat for any signs of discoloration. Sometimes the rear balance shaft seal will seep a bit & mist some oil on the top of the cat.

 

Otherwise, maybe you got a bit of oil on the block surface up inside the oil filter well when you changed the oil filter. That area gets pretty hot so if a bit of oil on the block up in there maybe you are smelling that.

 

[ed may]

Thanks for the input dirtrider, you are always on top of it. I will post if I find anything.

[mneblett]

Good timing for this thread to be rekindled -- the RT I picked up three days ago has exactly the same issue when warm: a moderate smell of hot oil. My smell-o-meter between my eyes and lips noted the smell to be strongest rising from the area around the steering head -- not really detectable near the left head or the right head.

 

I've had the tupperware off, and have run my eyes and/or fingers over every surface I can imagine oil might get to -- the oil cooler and lines to/from the cooler, sump and block top, oil temp sensor on top of the block, under the motor and tranny, cylinder bases and heads/valve covers, the vent hose from the left valve cover, around the oil filter, around the oil filler cap, etc. -- nothing found.

 

FWIW, it smells *exactly* like the burning-off oil small that it took me a couple weeks to find on my Corvette, which turned out to be an unseen single oil drop which fell on the exhaust manifold during refill of the engine at the first oil change. The drop spot had no visible residue, but on a hunch I drenched/wipred down the suspect area on the manifold thoroughly with carb cleaner -- that fixed it. I may do the same thing with the RT's head pipes and the cross-over pipe to eliminate that as a possibility.

[dirtrider]

Evening Mark

 

On your bike look really carefully at the fork seal area. Sometimes a drop or two of fork oil will come out & blow back on the hot pipes.

 

You might remove the front belt cover & take a look under there also.

 

[malcolmblalock]

As a follow-up to my original post, I've finally decided that the smell will just live with the bike. I've ridden over 11K miles since my initial post, and the odor is still there. It's not really strong, but it's definitely associated with the bike.

 

I've looked at every part that's been mentioned, and monitored fluid levels, and I have no idea where the oil is coming from. Everything is dry as a bone, and no evidence of oil residue anywhere. I know there has to be a leak somewhere, but it's invisible to me.

 

I've worked on vehicles on and off for more than 50 years, so I know there's a leak, and it has to be hitting the hot exhaust. But where it's coming from, or where it's hitting the heat, I can't see.

 

I'll live with it, and maybe somewhere down the road when I'm having some major service done (ie clutch or similar), it will be evident as to where the leak is.

 

Open to other ideas and suggestions, but I've stopped worrying much about it.

[mneblett]

Thanks, DR. I did so -- no evidence of fluid from the forks.

 

Last evening I used a towel and solvet (carb cleaner) to completely wipe down the head pipes and cross-over tube. Still have a light hot oil smell coming up from the steering head when the bike is fully hot, with no oil smell from the area around both valve covers.

 

Next step is to pull the front cover to see whether there's oil where it's not supposed to be on the front of the engine.

 

A related Q: I've not removed a camhead front cover -- anything different from an oilhead, i.e., anything to be careful about or tricks to make it easier?

 

Thanks,

Mark

[erikrichard]

For what it's worth, the R1150RT I test rode had the same oil smell and my '05 R12RT has it too but only sometimes.

[I812]

I stopped smoking 3 months ago.

No oil smell yet!

[mneblett]

Thanks, DR. I did so -- no evidence of fluid from the forks.

 

Last evening I used a towel and solvet (carb cleaner) to completely wipe down the head pipes and cross-over tube. Still have a light hot oil smell coming up from the steering head when the bike is fully hot, with no oil smell from the area around both valve covers.

 

Next step is to pull the front cover to see whether there's oil where it's not supposed to be on the front of the engine.

I pulled the front cover last night -- easy to do. Absolutely no wetness anywhere -- still stumped. Next step is to pull the tank and inspect the top of the engine!

[dirtrider]

 

Evening Mark

 

You still could have some oil misting from inside the trans housing. Usually shows up on the engine rear shown.

 

 

[mneblett]

Thanks, DR -- great pic/graphics, BTW!

 

I've checked there -- perfectly dry. That is consistent with the hot oil smell coming through the steering head area, and the lack of oil smell at either valve cover or either side of the bike below the rider's seat area.

 

As I have now physically closely inspected *every* exterior surface of the motor, throttle bodies, left vent hose, etc., except the top of the motor under the alternator (I did however verify no seeping at the oil temp sensor or oil cooler pipe fitting on the top of the block), I'm starting to consider alternatives.

 

One thought that has come to mind: a defectively-brazed oil cooler. The smell only comes after the engine is thoroughly warmed up, is most notable during and immediately after the bike has been moving, and dissipates pretty quickly after the bike is shut down.

 

I've checked the cooler hose fittings, and shined a flashlight through the cooler fins looking for oil stains -- none noted.

 

Keep the ideas coming!

 

Thanks,

Mark

[gordiet]

I have experenced that same thing. Never could find anything. Screw it! Ride it!

 

GT

[mneblett]

How long before the smell no longer appeared?

[malcolmblalock]

Mine has been present for at least 12K miles.

[gordiet]

Mine went away!

 

GT

[mneblett]

How long to go away? Just trying to get an idea whether I should expect it to be gone by the time I go in for the 600 mi. service.

[itspossible]

I've got the same smell, assumed it was just hot pipes. I did get a bit of Mother's chrome polish on the pipes when I was cleaning them so I thought it could be that. Didn't see any oil stains and the forks definitely are not leaking. I just ride it and keep an eye open for developments.

 

r

[gordiet]

Never could find a drop of oil anyplace. I took a trip of about 6000 miles and was in alot of rain and about half way through the trip I noticed that it was gone. Go figure.....

 

GT

[malcolmblalock]

Maybe I need to ride in the rain next time we have a frog strangler!