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[unlucky mark mv6]

Do a compression test mate,ive got one you borrow if your in the midlands.

[Lazydocker]

Sounds like stem seals to me... But as above, a quick compression test will confirm there's nothing out of order below the valves

[Kevin Wood]

I doubt brand or grade of oil will make a lot of difference, TBH.

My initial thoughts were that I wonder if the same batch of sh1te stem seals went on them.

IIRC, you said compression was great. Although that doesn't mean there isn't a problem with rings I'd say it makes it less likely.

Check breathers (oh, and while you're at it, start it up with a breather disconencted and see if there's a load of blowby) and if that doesn't fix it, schedule in a change of stem seals at some point. I guess you know the drill in that respect.

Nice, sweet running engine despite its' thirst. now the cam timing is right. 

Kevin

[jimmas]

does sound like stem seals to me as well.

[Taxi_Driver]

Taxi Driver - if you see this, maybe you can recall how much oil our trusty Veccy B went through?

I recall getting through about 3 litres on a trip to scotland and back, it drank oil like it was going outta fashion - however, never any smoke, or leaks... and it went like the clappers!

Not a lot of oil when i had it....2/3L per 10K miles....remember i had it rented out....and i had to buy the oil for it....only gave the driver a 5L tub every couple of oil changes...(10k between oil changes)

But i used vx semi synth on it.....i seem to recall you put full synth in it.....which would have been far too thin for it.......plus you had the top end apart to fix the broken valve.....that might have contributed to oil usage  :-/

[JamesV6CDX]

Been monitoring the situation -

200 miles, no noticable loss.

smoke when started from cold - and smoke when you rev it after it's been idling - whether hot or cold

But if you are say on an A road after normal driving, pull into a layby, and rev her hard - no smoke

Can oil get past stem seals at idle then?

[Kevin Wood]

Certainly sounds like stem seals to me.

Remember at idle the whole intake area is at about 1/3rd atmospheric pressure so rather than the stem seals preventing oil dribbling down the valve stems, there is 0.7 bar of pressure trying to force it down. Put the engine under load and the inlet vacuum drops.

In addition, I reckon oil is collecting in the intake tract or even the cylinder and not burning off until revved meaning the smoke is more noticeable then.

Do check the breathers are clear though, as any pressure in the crank case will make an oil consumption problem 10 times worse.

At least it sounds like it can be lived-with for now.

Kevin

[JamesV6CDX]

Certainly sounds like stem seals to me.

Remember at idle the whole intake area is at about 1/3rd atmospheric pressure so rather than the stem seals preventing oil dribbling down the valve stems, there is 0.7 bar of pressure trying to force it down. Put the engine under load and the inlet vacuum drops.

In addition, I reckon oil is collecting in the intake tract or even the cylinder and not burning off until revved meaning the smoke is more noticeable then.

Do check the breathers are clear though, as any pressure in the crank case will make an oil consumption problem 10 times worse.

At least it sounds like it can be lived-with for now.

Kevin

Breathers clear - the crankcase pipe is flowing...