M52 Valve stem oil seals.
Discussion
Thinking about buying a Z3 with tired valve stem oil seals. (runs fine, emissions perfect, but smokey on startup from cold)
Having looked at the design of the head, it looks to me like a tool made up similar to this -
Would enable the job to be done without needing to take the head off the car, as I know what a ball ache that can be on the M52 engine, with it's propensity for stripping threads in the block when torqueing the bolts down.
Anybody know of any reasons why this wouldn't work?
Obviously got loads of other considerations, like stopping the valves from dropping into the bores, but as a basic idea, has this got legs?
Having looked at the design of the head, it looks to me like a tool made up similar to this -
Would enable the job to be done without needing to take the head off the car, as I know what a ball ache that can be on the M52 engine, with it's propensity for stripping threads in the block when torqueing the bolts down.
Anybody know of any reasons why this wouldn't work?
Obviously got loads of other considerations, like stopping the valves from dropping into the bores, but as a basic idea, has this got legs?
If it's only smoking on start up why not just leave it? How much is the car and what's the condition? If its mint and you planning on keeping it it may be worth doing but there is a lot of work involved with camshaft and chain removal, just run it until its smoking all the time and then drop another engine in, you can probably get another engine for a couple of hundred quid., probably be cheaper and a lot less mucking around.
However we're these engines prone to valve stem seal failure? I have not come across this before as suggested try looking for gunk in the breathing system first.
However we're these engines prone to valve stem seal failure? I have not come across this before as suggested try looking for gunk in the breathing system first.
s m said:
Not telling you how to suck eggs, but have you checked the cyclone valve is OK?
If so, ignore me and carry on.....
PCV valve getting clogged would cause smoking all the time though, I would have thought. Only does it from a cold start. Smokes heavily for a few seconds, and then clears. Emissions absolutely spot on when warmed up, so it's not burning oil heavily in normal temp running.If so, ignore me and carry on.....
I'd be very happy for it to be PCV probs, but I don't think it is.
As for the car - it's an older one, a 98 R, but is very, very clean and tidy. Full BMW History, sits on pretty new P Zeros all round, and 79K. If I buy it, I'd like to keep it original if poss.
The complexity of the job doesn't over bother me - it's only nuts and bolts!
Rollcage said:
s m said:
Not telling you how to suck eggs, but have you checked the cyclone valve is OK?
If so, ignore me and carry on.....
PCV valve getting clogged would cause smoking all the time though, I would have thought. Only does it from a cold start. Smokes heavily for a few seconds, and then clears. Emissions absolutely spot on when warmed up, so it's not burning oil heavily in normal temp running.If so, ignore me and carry on.....
I'd be very happy for it to be PCV probs, but I don't think it is.
As for the car - it's an older one, a 98 R, but is very, very clean and tidy. Full BMW History, sits on pretty new P Zeros all round, and 79K.
Anyway, good luck with the job
I have a 1997 328 auto M52 ( Nikasil block...!) that does exactly the same as the OP's car ie puts out blue smoke on cold start up, this clears very quickly . It does not happen on warm starts, however I do get blue smoke sometimes when the engine is up near the 'red line' ( and there was evidence of it on my first track day...!!)
My first job was to replace the CCV which was a tricky job with the manifold in place (!) but in fact this has made no difference.
Talking to a mechanic pal, it was suggested that it was possibly a valve stem seal problem, and that it may be worth trying an additive ( Forte do one ) which restores the suppleness of the seals and may be an easier ( and of course cheaper ) way of solving the problem.
I will try this in the coming week, followed by a dose of Forte engine oil flush that should hopefully clean out any residue in the induction/breather system.
On a related note, my engine does consume a lot of oil ( as it did when my uncle ran it ), so I am hoping that this valve stem seal additive will help, as I am buying quite a lot of oil...!
My first job was to replace the CCV which was a tricky job with the manifold in place (!) but in fact this has made no difference.
Talking to a mechanic pal, it was suggested that it was possibly a valve stem seal problem, and that it may be worth trying an additive ( Forte do one ) which restores the suppleness of the seals and may be an easier ( and of course cheaper ) way of solving the problem.
I will try this in the coming week, followed by a dose of Forte engine oil flush that should hopefully clean out any residue in the induction/breather system.
On a related note, my engine does consume a lot of oil ( as it did when my uncle ran it ), so I am hoping that this valve stem seal additive will help, as I am buying quite a lot of oil...!
TheEnd said:
Nikasil bore wear or the crank case breather are far more likely that valve stem seals.
But wouldn't that show in general running, and on the emissions test? The HC count on the emissions was about 5 I think, I would have thought that sort of wear would put the figure through the roof. As I have said, it only smokes on cold start, not at any other time. Not even when given a good thrashing.
g3org3y said:
TheEnd said:
Nikasil bore wear
Would that show up on a compression test?I can't rule out valve stem seal wear, but there are certain things that happen a lot, and certain things that are pretty much unheard of, and stem seals on a BMW is one of those rare ones.
You can pick up a complete 328 engine for about £250, so bear that in mind when working out what to do.
Paul S4 said:
Talking to a mechanic pal, it was suggested that it was possibly a valve stem seal problem, and that it may be worth trying an additive ( Forte do one ) which restores the suppleness of the seals and may be an easier ( and of course cheaper ) way of solving the problem.
I will try this in the coming week, followed by a dose of Forte engine oil flush that should hopefully clean out any residue in the induction/breather system.
This is the procedure I will try this in the coming week, followed by a dose of Forte engine oil flush that should hopefully clean out any residue in the induction/breather system.
http://www.forteuk.co.uk/ForteAdmin/Bulletine_PDF/...
Would be good to know if it works.
g3org3y said:
steve_bmw said:
If the engine is original and in a z3 it won't have nicasil block because it was made in USA. Think I'm right.
Had a quick search online and it does appear that Z3s didn't suffer Nikasil issues. Thanks for the info, every day is an education on PH. It does look like they were all made at the Spartanburg plant in the US.
from wiki-
"In 1997 a more powerful 6-cylinder engine was added. The 2.8 L engine (M52B28), similar to the BMW M52 straight-6 in the 328i except with an all aluminum block and head, was especially desirable with its 189 hp (141 kW). "
That's were it gets strange, I thought all US blocks were the cast iron M50 type, unless they are actual Alusil blocks, or the UK style "Alusil" which is really a steel liner but gets all confused on the 'net.
Edited by TheEnd on Sunday 2nd June 16:14
http://www.honestjohn.co.uk/forum/post/index.htm?t...
From that post - "Just phoned BMW GB. The Z3 2.8 was not affected."
From that post - "Just phoned BMW GB. The Z3 2.8 was not affected."
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