Blueish white smoke

[Hypr5]

Hey guys,

I'm trying to sell my 90 525i (m20 power)
but before I do I want to make sure she is near perfect for the new owner.
Just today, I started it up and a little rev to 2k showed a noticeable amount of blueish white smoke. I had never noticed this before and I don't know exactly what would cause this. From my experience a headgasket would make the smoke whiter and right upon startup - but this only happens when I rev it a little bit.

Any ideas, suggestions??

Thanks.

[Alexlind123]

Well, you could be burning oil, but that usually happens slowly i think. Someone else will probably know more.

[rob101]

Hey guys,

I'm trying to sell my 90 525i (m20 power)
but before I do I want to make sure she is near perfect for the new owner.
Just today, I started it up and a little rev to 2k showed a noticeable amount of blueish white smoke. I had never noticed this before and I don't know exactly what would cause this. From my experience a headgasket would make the smoke whiter and right upon startup - but this only happens when I rev it a little bit.

Any ideas, suggestions??

Thanks.

valve seals are a good place to look they usually make smoke on start up but not really at other times (personally my 528i does that) i wouldn't rev the engine just after you started up

[Hypr5]

Thanks for the tip.
Yeah, I usually don't rev it at all
Just 2k seemed "safe" especially since I don't ever do that until it's warm.

Kind of glad I did now though - since I discovered a problem before I sell it. <sigh>

It definately does not smoke at all when warm unless it gets close to rev-limiter, but then it's just a touch of black smoke which I am told is normal.

[rob101]

Thanks for the tip.
Yeah, I usually don't rev it at all
Just 2k seemed "safe" especially since I don't ever do that until it's warm.

Kind of glad I did now though - since I discovered a problem before I sell it. <sigh>

It definately does not smoke at all when warm unless it gets close to rev-limiter, but then it's just a touch of black smoke which I am told is normal.

yeah well actually it is probably okay, i caught my dad revving my 528i the other day at start up, good way to **** the engine since the oil pressure light is slow to go off on start up, (yes i know i am going to check my banjo bolts). but my father is not very bright when it comes to cars . He is a civil engineer so he can't grasp the concept of lubrication. you'd think a father would take care of a free car you lend him, but within a couple of month he has backed it into a pole already and that stupid revving ********.

Anyway a bit of black smoke is probably normal at high rpm, its just the car running a bit rich. best to just start her up and let oil circulate for half a minute or so before setting out... start up is when most wear occurs. we all do stupid stuff with regards to flogging an engine when cold etc. and yeah, oh well. you can't be perfect all the time but try to be good 80% of the time lol.

[skr]

blue smoke =burnt oil. ain't nothing else producing that. valve seals are one place to check but the most common cause of burning oil are the good ol' piston rings.

[Hypr5]

Would the smoke still go away after the car is warm if it was rings? I'm guessing yes. Compression check the only way to go here?

So basically... the car is totally worthless at this point??

[skr]

Why whould the car be worthless? minor ring wear isn't the end of the world.
as the engine warms up the pistons (aluminum) expand more than the cylinder linings (steel), reducing the gap.

[rob101]

Would the smoke still go away after the car is warm if it was rings? I'm guessing yes. Compression check the only way to go here?

So basically... the car is totally worthless at this point??

no its not totally worthless at this point..... if you want to go nuts and think your engine is shagged then fine do so, but the reality is that in all likelyness its not your rings, and if it only happens at start up and you don't see large amounts of oil lost (in the sump) then don't worry about it..... drive the car for X years get a rebuild. you already own the car so you can't really do alot about it and its not worth doing so unless its so bad that you need you own oil field to supply it with oil.

[Hypr5]

Well, the engine does run smooth and feels like it always has,
but thats something I certainly wouldn't be able to afford to fix (in terms of downtime if I were to do it OR financially for a shop), and I'm not sure there are many people who would want to buy a car that smokes like that. Maybe thats just me... I don't know.

I hope it's something wrong on a smaller scale.