blue smoke

jayne58 · Post by **jayne58** » Sat Jul 25, 2009 3:14 am

Hi guys, I am Jayne and new to the forum. I am in the process of restoring a 1981 528i 5 speed . Yesterday i had it running after nine years in hybernation. Is it normal to have a bit of blue smoke from the exhaust due to the fact that it wasn't running for a long time? I was not able to have it run longer (less than 5 minutes) after a water hose broke. I am hoping that it is not piston or oil ring related. I will try it again tomorrow and make it run longer to see if the smoke disappears or at least lessen. Does anybody have any idea? Thanx!

Mike W. · Post by **Mike W.** » Sat Jul 25, 2009 12:48 pm

If it hadn't run in 9 years, it might clear up after running a bit, but more likely is it needs valve guide seals. The pistons and rings hold up pretty well, but the valve guide seals not so well. The good part is it can take a smoking engine and turn it into one that doesn't use oil, the bad part is you have to pull the head to change them.

jayne58 · Post by **jayne58** » Sat Jul 25, 2009 5:29 pm

Thanks mike, I believe you are right. I was able to have it run longer today after fixing the water hose and it didnt change, (still a lot of smoke). The engine idles good though and starts right up. Well yeah, I will just take C head out and change the seals and guides as well I also think the thermostat is not opening up, the temp gauge passed the half mark so i decided to call it a day. Thanks for the Info.

GripGreg · Post by **GripGreg** » Mon Jul 27, 2009 5:49 pm

Jayne, before you take it apart, smell the exhaust coming from the tailpipe. I know, I know, but if it smells at all like anti-freeze it my be the head gasket or worse,, the infamous cracked head. While apart, you may as well get a valve job along with the valve guides. Very cheap insurance since you're already in there. Ask me how I know? Good Luck,,,,Greg

jayne58 · Post by **jayne58** » Mon Jul 27, 2009 10:40 pm

Thanx for the info Greg, I will keep an eye on that or should I say a nose on that LOL ....appreciate it buddy.

DMS · Post by **DMS** » Tue Jul 28, 2009 2:03 am

Measure compression aswell before you take it apart. Run the engine till it's warm and check your coolant for oil or gasbubbles. (Measure CO but it's unlikely you have easy access to that.) Take the valve cover off and check for mayonaise/slush.

I would just run the engine as it is for a bit and see if it's getting better in week or two. If it's still smoking blue smoke then take the head off and pressurize it. Then replace everything, all gaskets and do a clean and valve job.

jayne58 · Post by **jayne58** » Tue Jul 28, 2009 10:43 pm

I did a compression test this afternoon and here are the readings in psi.

1....175
2....175
3....172
4....172
5....175
6....178

I dont know what the range is so I need you guys to tell me if this is good or not so good. Thanx again. As with the gas bubbles in the water reservoir I dont see any. No milkshake inside the valve cover. One more thing I noticed is the sparkplugs are all wet when I pulled it out I dont think its all gas it has some oil in it, but still the engine idles good and start right up, So I dont know, calling it a day again. Thanx.

Jayne

GripGreg · Post by **GripGreg** » Tue Jul 28, 2009 11:44 pm

As of now, I prefer to call you Jay. So Jay, since your compression test scores are so close, I think your rings are good. The BMW doctors here know more than me. But, after thinkin' about it, since the car sat for 9 years, the valve guides may need replacing anyway. Don't they need to be lubricated to work properly? Maybe in time they'll be OK. I just like to spend the little bit o' knowledge I have. Small shade tree here. Greg[/i][/u]

GripGreg · Post by **GripGreg** » Tue Jul 28, 2009 11:53 pm

Sorry 'bout this double-type of post. But, you said the word 'it', implying just one spark plug. If you meant all of the plugs, maybe you should try plugs that are one step hotter. Because of the oil & gas residue? MAYBE.

Greg Again

jayne58 · Post by **jayne58** » Wed Jul 29, 2009 12:25 am

Thanx Greg, Yeah all the sparkplugs are the same, all wet, I havent change them yet they are the once in the car for the last nine years or so it was sleeping. they are WR9DC, what do you suggest I replace them with? Just a thought is there any possibility that the smoking is because of the bad sparkplugs?

GripGreg · Post by **GripGreg** » Wed Jul 29, 2009 12:53 am

New plugs always make a differance. Especially after nine years, c'mon?Not a cure-all though, NINE years?? I would also change the distributer cap. NINE years?? Maybe the wires later. NINE years?? What did you do nine years ago? Perform a lil better, maybe?? I know I did!

Greg

jayne58 · Post by **jayne58** » Wed Jul 29, 2009 1:15 am

hhahahaaha I know I'll get that reply, nine years!!!!! LOL.

jayne58 · Post by **jayne58** » Thu Jul 30, 2009 12:37 am

I changed the sparkplugs today, made a lot of difference in idling but the smoke is still there specially when I rev it. The more I rev it, the more smoke I get.

GripGreg · Post by **GripGreg** » Thu Jul 30, 2009 1:06 am

Have you put your nose in the smoke & taken a good whiff?? Blow your nose later, but do that. You don't have to rev it up & dash to the tail pipe; just waft the smoke toward your nose & sniff. I know I smelled anti- freeze, meaning either a head gasket or worse. How many minutes has the car run after the new plugs? I think,,let it run awhile. Maybe somebody else can be more helpful here.

jayne58 · Post by **jayne58** » Thu Jul 30, 2009 8:02 pm

The car run for a good 15 minutes but the smoke remains. I did that sniffing thing, It smells gas and burned oil. I have a bad radiator so I don't see too much circulation in the coolant reservoir hence I don't see bubbles there which would suggest compression going to the water system. The smoke is there be it idle or revving, I mean its not an on off thing, always there. More info wpuld be appreciated before I start dismantling the C head.

Thanx guys,
Jayne