Blue Smoke - KV6

[sworks]

Originally Posted by Lovel

The A series engines is a number of generations before the K engines were even thought about, materials and engineering have evolved so much over this time, therefore the A cannot be compared. To date I have never came across a Kseries or KV6 with damaged valve stem seals, and hence I believe unlikely in this case.

Slightly off topic. This reminded me of a time in the MGR days probably around 2003ish, the machine that installed the valve stem oil seals was faulty and a few would fall off whist the machine was installing them. It apparently went unknown until a worker found lots of valve stem oil seals on the floor. I had about 4 or 5 cars with missing valve stem oil seals to repair due to using oil. All K16 and not related to V6 and the only time I’ve had valve stem oil seal issues, but a happy memory of days gone bye. I miss the MGR days.......

[350zwelgje]

Crankcase ventilation is key. If not ok, as mentioned before, oil can be present in the inlet of the engine and will get burned.
Have oil present at the throttle myself, not yet blue smoke at startup, but like to rev it at least once a day to full rpm..... And thus probably sucking the oil in before it gets parked up.

Need to replace the inlet manifold (rattling stuff etc) and will replace crankcase ventilation hoses/connections and clean the pinholes and wire wool in the cam covers. That will sort it on my KV6.


Rob

[Gate Keeper]

Originally Posted by chris75

ElHocko , I would be interested to know how you got on with this ?
Out of the blue , so to speak , my kv6 car has started to do this
First sign was this Tuesday evening , then twice more including today . In each case it is a cloud of blue smoke from a cold start and then no more problem whilst running . Negligible (zero ) oil consumption and on the MOT last week emissions were excellent , and no sign of smoke when starting whilst still warm.
My own thoughts were initially worn valve stem oil seals , but this is not reported on the kv6 , and I don't see that this would happen so suddenly if that were the cause The suddenness seems to suggest breakage rather than wear ?
As suggested , I will be following the routes of compression test and breather clean-out in the near future , plus a spark plug inspection ( oh , how I hate those back 3 plugs ! )
My car is a kv6 , 2001 reg with 113k miles on it , and is running beautifully otherwise .

I am in the same boat. MOT and service last week, passed. Blue smoke on cold start up for 20 seconds, then it disappears and does not return whilst driving. This has been going on for 3 years. At one of the local meets, one of the gurus in attendance told me it was the valve stem oil seals and it would be easier for him to replace the engine than do the job. Low mileage per year 2000-3000, so I live with it. The purists won’t like that!

It’s a little embarrassing. I have seen the tree hugging neighbours turn up their noses and make a face when they see the smoke. Apart from this, the car is a lovely drive. Incidentally, along with OVP, it will be 20 years old next month.

[Rich in Vancouver]

I see that no-one has responded to the question about an oil catch tank.
I haven't had a smoke on start up issue but the KV6 in my Freelander had a lot of oil in the intake. I installed a catch tank (cheap from Amazon) in the breather line but was disappointed to find it only collected a little oil.
It has been on about 6 months now and I recently had the intake manifold off to change the T-stat. I was happily surprised to find it had very little in the way of oil deposits inside, so the tank may be working.

[Gate Keeper]

Originally Posted by SD1too

This is vital evidence, thank you. It definitely points to a strong possibility that it’s a valve stem oil seal. What happens is that oil slowly seeps past the seal into the combustion chamber and is then burnt when the engine is started, producing the instantaneous blue cloud which you have seen. I experienced this years ago with a Mini which had been fitted with a poorly modified cylinder head.

Simon

Simon I am curious. Apart from examining the seals, is there a definitive test to confirm the blue smoke is down to the valve stem seals?

[Rich in Vancouver]

Back in the day we would do a compression test.
If a cylinder is low it is generally either the rings or the valves.
Once you find a cylinder is low you squirt some motor oil into the cylinder
then repeat the compression test. If the pressure goes up that means it is the rings (now sealed by the oil) if it doesn't go up that means it is the valves.

[Avulon]

Originally Posted by Rich in Vancouver

Back in the day we would do a compression test.
If a cylinder is low it is generally either the rings or the valves.
Once you find a cylinder is low you squirt some motor oil into the cylinder
then repeat the compression test. If the pressure goes up that means it is the rings (now sealed by the oil) if it doesn't go up that means it is the valves.

Just note that this won't help diagnose leaky valve stem seals at all.

[SD1too]

Originally Posted by Gate Keeper

Apart from examining the seals, is there a definitive test to confirm the blue smoke is down to the valve stem seals?

In my admittedly limited experience of this fault Phil, I’d say that the plume of blue smoke visible only after the engine has been standing for some time is proof enough. Can you think of any other fault which would cause these precise symptoms?

Simon

[sworks]

Originally Posted by SD1too

In my admittedly limited experience of this fault Phil, I’d say that the plume of blue smoke visible only after the engine has been standing for some time is proof enough. Can you think of any other fault which would cause these precise symptoms?

Simon

As Simon has said, valve stem oil seals generally cause smoking from cold or going down hill with no throttle