UR-q blue smoke

[Paul Heneghan <paul.heneghan@bbc.co.uk>]

>The problem is only on overrunning; a brief puff on very hard up changes
>(c. 6500 revs) and when decelerating from high revs (such as lifting off
the
>gas on the motorway or going down hills off the gas). I'd like a good idea
>of the likely source of the problem before I go ahead and take the head off
>again or remove the engine to have a rebore.

Not a very satisfactory answer, I'm afraid, but I think the standard
seller/garage comment applies here:  "They all do that sir".  Even new cars
(by new I mean up to a couple of years old), give a puff of smoke when
changing up at red line.

My 80q has smoked on the overrun since about 80k miles.  In Germany in 1991,
I did 110mph for a couple of hours, then some berk pulled out in front of me
and I lifted the accellerator and stepped on the brakes.  This was
accompanied by a HUGE cloud of smoke as all the hot thin oil got sucked into
the combustion chamber.

It now uses a little oil (1 litre in a couple of thousand miles), but I have
never had the urge to replace the valve seals.

Paul