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smoke coming out of exhaust after oil change

tsugha

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Hello there,

My bikes oil and filter recently changed in a service, they drained the bike and put new filter and 3.5 lt oil (motul 5100 10w40), a little smoke came off the exhaust when we start the bike, service said it will be gone in 100-200 kms. They didnt check the oil level with cap after change, asked them to do so, but replied they know how much it requires.

After leaving service, i started the bike again that evening, much more smoke came out, and smoke flow reduced once the engine is warm again. We checked the oil level and it was 6-7mm more than the high level mark. (bike was upright and engine was just warm and we didnt screw the stick while measuring).

1- have any one experienced how much mL excess oil it takes to make the level mark that high.
2- i'm wondering if that amout of excess oil can hurt piston rings or valve guides or something to make the bike burn oil.
3- bike was drained in sidestand, is it enough to drain it properly to make it stand still while draining or moving bike left/right is required to fully drain the oil.
4- service claims that they didnt fill the bike more that it requires. they called the bike back after my complain and handed me later the day after, and when i check oil level again, it was between two lines.

i'm kinda in a trouble. Please share your experience.

Regards,
Tolga
 
#4 ...... learn to change your own oil and filter...

you won't wonder about how much oil is in then.

it would be a good idea to remove the oil filter (replace it) and make sure the "O" ring on the filter is :
a) coated in oil
b) seated properly on the oil filter itself

I am not enough of a mechanic to know what cases the exhaust to be black, but these are small, relatively, easy steps you can take.
 
Is it still smoking after the second visit to the dealer when they removed oil ? I suspect that they overfilled it. According to the specifications on my X-Adv which is also DCT it takes 3.4 litres with oil and filter change. Accordingly they over filled by at least 100ml. I think Your bike is a standard gearbox so perhaps it takes even less ?

I am not sure why it is smoking though even if it was overfilled.
 
Is it still smoking after the second visit to the dealer when they removed oil ? I suspect that they overfilled it. According to the specifications on my X-Adv which is also DCT it takes 3.4 litres with oil and filter change. Accordingly they over filled by at least 100ml. I think Your bike is a standard gearbox so perhaps it takes even less ?

I am not sure why it is smoking though even if it was overfilled.

Mine isnt dct, and yes still smoking. It also blows air like crazy if i open the oil cap when it is running on idle, i think it is a sign of defected piston ring(s)
 
Mine isnt dct, and yes still smoking. It also blows air like crazy if i open the oil cap when it is running on idle, i think it is a sign of defected piston ring(s)

curious if you would be able to post a link to a video like on youtube?
 
This is a very, very bad sign. How long has it been doing that?


No, I don't think so for that part - I once forgot the dip stick open and pressured air was coming out and spit oil on me... that part I believe is fine, the oil dip stick should always be tight unless checking the oil level.
 
I watched your video man - I'm sorry but unless it's super cold where you are right now, that does not look good - maybe some of the more experienced senior members on here like 670cc, dduelin, etc... can chime in...
 
I am not a mechanic, so I dont know if motorcycles have 'head gaskets', but I do know a blown head gasket in a car will cause the same problem. Tsugha-check your coolant level-has it changed (went down). When you check the oil after running the bike, is there a white frothy foam on the dipstick?
That exhaust looks more like coolant getting into the oil and going thru the engine (where it isnt supposed to be). Any mechanics on here who knows if motorcycles have head gaskets or its equivalent?
 
Here is an optimistic explanation of what may be going on:
When overfilled with oil, the extra oil can splash around and get sucked/forced into crankcase vents and other places it is not intended to go. Then it can get sucked back into the intake and get burned in the cylinder, producing smoke.

If some oils gets blown through the engine and into the exhaust, it will smoke for quite a while until it all burns away.

I've had bikes, lawnmowers, generators, etc smoke before after the engine tipped over allowing oil to flow where it didn't belong. After a while, the smoke went away and all was fine.

JT
 
Here is an optimistic explanation of what may be going on:
When overfilled with oil, the extra oil can splash around and get sucked/forced into crankcase vents and other places it is not intended to go. Then it can get sucked back into the intake and get burned in the cylinder, producing smoke.

If some oils gets blown through the engine and into the exhaust, it will smoke for quite a while until it all burns away.

I've had bikes, lawnmowers, generators, etc smoke before after the engine tipped over allowing oil to flow where it didn't belong. After a while, the smoke went away and all was fine.

JT

nc750 got head gasket, how can i understand if it is coolant or oil?
i always though if it was coolant then it would eventually condense and disappear if you run the bike in a closed and cool enclosure. (i run it in a closed garage and smoke didn't disappear for more than 5 mins, then i left the place due to smell)

stick wasn't foamy when i check.
 
Here is an optimistic explanation of what may be going on:
When overfilled with oil, the extra oil can splash around and get sucked/forced into crankcase vents and other places it is not intended to go. Then it can get sucked back into the intake and get burned in the cylinder, producing smoke.

If some oils gets blown through the engine and into the exhaust, it will smoke for quite a while until it all burns away.

I've had bikes, lawnmowers, generators, etc smoke before after the engine tipped over allowing oil to flow where it didn't belong. After a while, the smoke went away and all was fine.

JT

i rode like at least 100 km, still smoking. and at the moment i'm afraid if it may get worse if i keep riding.
 
Burning oil will smell like... smoke from burning oil. The color would be a light smoky bluish color.

Burning coolant will essentially be a form of water vapor (steam) and would not necessarily smell burnt. Depending on the coolant, it could smell sweet. It would feel humid or wet if you put your hand in the exhaust coming out of the muffler. The color would be more white, like steam from a boiling pot of water or like when you start a car in the winter.

I had a car with a blown head gasket. The big clouds of white, sweet smelling smoke was very different than burning oil.

JT
 
Mine isnt dct, and yes still smoking. It also blows air like crazy if i open the oil cap when it is running on idle, i think it is a sign of defected piston ring(s)

That is normal crankcase pressure afaik. I did it once on a Yam XS2 650 and got covered in oil.
 
Referring to what has been said above there is one other possibility. If the crankcase was over filled (which it was) then there is a good chance that the excess oil may have been blown into the airbox and is therefore being recycled through the fuelling system. There are vents from the air box to allow accumulated oil (from normal excess) to drain out. Your handbook should tell you where they are. I suggest opening these or it, if there is only one, and see what happens. If I am correct you should get a lot of oil coming out. The other option is to open the airbox and check the situation first hand. However I would try the vent first.

Otherwise the blue smoke is totally abnormal and because it has only happened since the oil change it is the responsibility of the shop to sort it out.
 
Having oil splash out the dipstick hole is very different from air being pushed out in high quantity. Oil splash is just because of the gears slinging it. Air is from blow-by, and in connection with significant oil smoke is a very bad sign.

HOWEVER, I was forgetting that the NCX is an odd firing order, and so as long as the engine pulls basically the same amount of air back in the oil fill hole as it blows out each crank rotation, then it’s normal.
 
A cylinder compression test might be a good idea. It’s simple to do as long as you have the tool.

I’m away from my service manual so I can’t research this, but another thought that comes to mind is crankcase ventalation. Somehow the crabkcase is being pressurized and causing oil blow-by?

As mentioned before, a confirmation of whether oil or coolant is being passed is important. Is the coolant level remaining stable?
 
As mentioned by others check the air box ( air filter box)........if it was run with way too much oil in the crankcase the air box will be “full” of engine oil. It won’t stop smoking until the box is completely cleaned.

Way too much oil to cause oil in the air box issues is not just slightly over the full mark.........way too much would be 1-2 quarts extra.

If the air box is clean look other places as mentioned by others.

Coolant “smoke” will have a very distinctive sweet smell.
 
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