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.

[skr]

there are a couple of easy things to do for you to get an idea about the amount of ring wear.
1. lift the dipstick (engine running).if you see a noticeable amount of smoke ,well , that's not too good.
2.after you driven your car for a while stop the engine and take off the valve cover cap ( use a rag or something because it's HOT) . if u see some fumes rising it's ok. if u see a lot, it's not ok.

remember, these are very empiric things and don't acuratly show anything. just to get an ideea of the situation.

P.S: some people say that excesive fumes in the valve cover mean worn valve seats or bad valve or something. not necesarely. in most cases those fumes actualy come from the sump, through a big hose wich has the purpose of taking those fumes in the valve cover because of their great lubrication properties.

[SRR2]

True story: My 83 year old neighbor has some mid '90s generic Buick wagon. Every time I hear the garage door open I know what's coming. Buick starts and he holds the pedal to the floor. No, not the brake, the gas. Asked him "Bob, how come you race the engine like that when you start your car?" Sez "Cos it gets rid of all that white smoke."

[laguner]

Blue smoke only at startup is probably valve seals as stated earlier.

[Dave M]

Sez "Cos it gets rid of all that white smoke."

Soon to be replaced with blue.

Funny

[632 Regal]

what oil are you using? If it's 0w-40 M1 then step up to 15w-50 if your selling it, this will significantly reduce blowby if its worn rings but I cant see that being the problem at 136k unless it was abused with shitty oil.
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.

[SC David]

You're giving up on your car too!? What automobile is in your future now?

Good luck with the situation! My car seems to be having minor problem after minor problem now too, but hopefully it will all get sorted out soon enough. Before you know it, I'll be the only M20 E34 on the face of the Bay Area!

[Hypr5]

You're giving up on your car too!? What automobile is in your future now?

Good luck with the situation! My car seems to be having minor problem after minor problem now too, but hopefully it will all get sorted out soon enough. Before you know it, I'll be the only M20 E34 on the face of the Bay Area!
Hey David...
yeah I don't know what it is, but this is by far the most unreliable car I have dealt with. Even out of other BMWs. I don't know why. The car has been meticulously cared for, I mean... EVERYTHING has been replaced and its just problem after problem. It's incredible. The m50 e34s don't seem to be this way (from my experience) but it's the same car except for the engine. Maybe just because ours were early in the model line up? Ugh. I really am starting to hate the car. I have all records since day one and seriously... the totals add up to damn near the original cost of the car.

Anyway, to answer the oil question - I'm using 20w-50 as recommended by the manual and many m20 owners. What's wierd is I always change the oil every 3k on the mark and it's NEVER shown signs of burning oil and on this last oil change, there was over a quart not "missing" Very wierd...

The thing is, I personally don't care anymore, but I just hate to sell a car that smokes on start up. I am sure that that brings the already pathetic amount that this car would bring in down even more. hmmmm... Maybe an m20 rebuild is in order. Can't be that expensive anyhow - just some time.

I Talked to the local shop and they mentioned that if it was upon startup, its most likely valve guides / seals, but if its when you get on the gas a bit then its likely the rings. It sure sounds like my case is rings.

Thanks for all the helpful replys everybody. It's much appreciated.

Don.

Side note: 3 years ago, I had a compression check done. I don't know the method they used to check it, but the numbers were 135 in all cylinders. Sounds odd to me. They said it might be a "little low" but the even wear indicates a well cared for engine?? Is that right?

[632 Regal]

you got the answer right there, dino 20w-50 oil. change it to some mobil 1 synthetic and your blue breath will most likely go away. Not to go on and on but dino oil is way way old school from what synthetic is today!!!

edit: 20w-50 dino dont flow cold where M1 0w-40 does and seals right out of the box.

Might be well worth the investment and if not drain it out and use it in your new car.

there are more 525s out than most other e34s all together and 136k is almost nothing. like I said dino oil and not enough changes before you bought the car could have worn the rings but I doubt it.

go back to synthetic and it hopefully will be a different world for you.

Good luck!

[Hypr5]

Hey man, thanks for the tip.
I'll give her a change with somethin thinner. I hear a lot about people developing leaks on shot seals by changing to synth. You think I will have a problem? I certainly hope not. lol. anyway, I'll give it a shot and see how that goes.

[Hypr5]

One more question -

The valves have been pretty ticky-sounding lately, much much more than normal. Although the car did have a recent valve adjustment (3k ago).

Could improper valve adjustment cause this kind of thing if its way out of spec?

edit: nm, it only happens when it's cold. I forgot. lol
and: can valve seals be replaced on the m20 without complete head removal?
I saw over at http://bmwe32.masscom.net/ that it is possible on the m70 and I know the m20 and m70 have many many similarities. Any input?

Thanks

[ILoveMPower]

My indy BMW-specialized mechanic recommended that I never run synthetic oil, as it will leak through the gaskets. Him and his father have been working on BMW for years and years, I'm curious as to why they would say this if I should be running synthetic?

[Hypr5]

After a cold start this morning, I couldn't get the smoke again, just clouds of steam. interesting...

[632 Regal]

because they are old school and dont believe in changes in technology? I would avoid them like the plague. Do some research on the subject, or better yet go to the search sticky and type in synthetic, im sure theres more than 1 debate on it..
My indy BMW-specialized mechanic recommended that I never run synthetic oil, as it will leak through the gaskets. Him and his father have been working on BMW for years and years, I'm curious as to why they would say this if I should be running synthetic?

[skr]

well, this points out that maybe there's another problem. did the steam stop afte engine warmed up? did u check your coolant level?

[Hypr5]

well, this points out that maybe there's another problem. did the steam stop afte engine warmed up? did u check your coolant level?

yeah, the steam stopped and the coolant level seems to be where I left it. Although I do have an overheating issue that is unexplained. ( I do think it is the fan clutch, though )

I really need to sell this beast, but I hate to do it without knowing whats wrong with it. I'll play with it some more. I took the car for a really long drive and opened the dipstick and oil cap and saw no fumes whatsoever, didn't smell abnormal or anything, either. But the valves are getting so sloppy that I can hear those things clapping in the car at 2k rpm. Time to adjust again.

[632 Regal]

whats the overheat symptoms? if the fan sounds like a schoolbus when cold its usually good, do the aux fans go on with the AC? if so check that they do when its running past half guage.

[Paul in NZ]

a little oil smoke on startup or a rev and trailing throttle is normal for an ehgine that is not brand new...I think you are a little hyped...relax and sell the car if you want.....
As for synthetic oil in a 535...guess what the dealer would put in it????(well they would here)

[Hypr5]

whats the overheat symptoms? if the fan sounds like a schoolbus when cold its usually good, do the aux fans go on with the AC? if so check that they do when its running past half guage.

Yeah, it sure doesnt sound like a school bus. It used to sound like that when it got hot, but not any more. The aux fan doesn't come on when over half temp. It will only come on if the AC is on.

[Hypr5]

a little oil smoke on startup or a rev and trailing throttle is normal for an ehgine that is not brand new...I think you are a little hyped...relax and sell the car if you want.....
As for synthetic oil in a 535...guess what the dealer would put in it????(well they would here)
Well to me its not a huge deal, I'll live with it as I know the car and it doesnt feel any more powerless than usual or anything - just an idle that has recently developed thats rougher than a big rig (no exaggeration).

However I'm just a little unhappy that I noticed this for the first time after I had decided to sell the money. I got a bit tied up into another car and just feared that if somebody wanted to, they could "bargain" the car down even more. It's already not even worth much. :(

I really appreciate all the help!