For those of you with long memories, you may recall that a bunch of us had new PCV valves fitted in the hope it would cure smoky turbos.

 

Well, mine did - sort of.

 

The symptoms (for me, anyway) were that in normal use, no smoke. But when it had been left in idle for a period of several minutes (eg at an MOT test), both exhausts would start to blue smoke. This disappeared after a few minutes of normal driving.

 

But still worrying.

 

I had the PCV valves replaced in June and everything seemed to be fine. During the next MOT (Aug) the smoke returned - first from the left bank then the right. But a lot less than it used to be so clearly, clearing the breathing problem (caused by gunky PCV valves etc) had a good effect.

 

During some other work, I asked the mechanic (Steve at Lucas Garage) to give the turbos a good inspection and checkover as I was concerned about the smoke. He reported that they looked fine with no leaks (one was bone dry and the other had a slight oil smear but only what you would expect on something in a 14 year old engine bay). They sounded fine as well.

 

His opinion is that this smoke is not from the turbos but indicates a very slight valve stem leak. And, at the current stage, not worth doing anything about.

 

Now of course you have to be sensitive to blue smoke as this can be very serious. So don't use this story as an excuse to do nothing! But I though you might be interested anyway.

 

Toodle-pip - Gio

Valve stem seals going would tend to show up mostly after the car had been stood for a while - a cold start would give plumes of blue smoke.

 

Blue smoke points to oil being burnt in the combustion chambers - if the rear seals were leaking on the turbos you'd be more likely to see a white hazy smoke.

 

It may well be worth just checking that the breather hoses haven't got sludged up again - they should still be soft enough to remove without damaging them and then just spray through some carb cleaner. The only hoses you need to do this to are the front ones.

 

HTH

 

CheerZ,

 

Andy

Originally posted by andyduff

Valve stem seals going would tend to show up mostly after the car had been stood for a while

 

or on over-run ;) - when theres high engine vacuum

Originally posted by Paul C

or on over-run ;) - when theres high engine vacuum

 

Or when jupiter and saturn are lined up with mars.....

Originally posted by andyduff

Or when jupiter and saturn are lined up with mars.....

 

no,no!! they have to be inline with Uranus :D

Could be due to the Earths' current proximity to Mars ! ;)

I've just had yet another thought on this:

 

Maybe its the hamsters that spin the turbos? I reckon, if the car is left to idle for any time, the hamsters get bored and start skinning up, if you leave them long enough, they will complete the 'build' and 'spark up' hence the smoke from the exhausts....

 

Gotta be true init :D

But surely they'd have to wear some sort of suit...any ideas?? :confused:...

ASBESTOS!!!!!!!! :D

Originally posted by andyduff

ASBESTOS!!!!!!!! :D

 

thought everyone knew that!!! :D :rolleyes:

Gio

how easy is it to replace valves

Originally posted by wez

Gio

how easy is it to replace valves

 

its quite a simple little job really, a little fiddley to get to them but not too bad :)

http://www.ttzd.com/tech/pcv/pcv.html

Hi Gio

What oil are you running? I changed my PCV's and the smoke reduced. I then changed the oil from 10w-40 to 20w-60 fully synthetic......... No more smoke :)

 

Jon

Hmm, interesting idea. Usually use Castrol Magnetec but forget which. I'll check at next service.

 

Cheers - Gio

It was magnetec I had originally in mine.