[Healeys] Help - Oil smoke in exhaust

[Alan Bromfield]

Team.
I need some direction from your collective wisdom. A fellow club member with
a MkIV Sprite has a recurring problem on his freshly rebuilt engine. 

Soon after startup if the car is left to idle for about 3 or 4 minutes it
starts to smoke, quite badly. After another couple of minutes or so, the
smoke clears and from then onwards everything is clean and sweet. We thought
it was a matter of rings needing to bed in, so the car has had about 40 - 50
miles of gentle running but it has made no difference.

The oil level has been reduced by just over a pint so that it is registering
about halfway between min/max on the dipstick (figuring we might be
overfull), but it has made no difference. Oil pressure is very good. I guess
the clue is that there is highest vacuum (manifold depression) when idling
but where can the oil be coming from? If it were valve guides surely it
would get worse as the engine gets hotter. If it's oil control rings I
figure we would see oil smoke when driving.  This is only when idling and
only as it starts to warm up. Not when cold (first started) and not when hot
(after a drive). It seems to start as the temperature begins to rise on the
gauge.

If it were dashpot oil it would have all gone by now I would have thought.
What else might be the source/cause? We are all flummoxed here.

Any ideas? All suggestions gratefully received.

Regards
 _______________________________________________
(______________  Alan Bromfield  _______________)
   (______     \____1957-BN4 ___/    _______)
          (_________________________)
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