Blue Smoke on acceleration - Help

P

p6baseunit

Member
Topped up the engine oil yesterday to the high mark, it did take a bit of oil, as it was almost on the low mark ( al least a litre of 20w50) and I noticed on starting the car that it puffed a little blue smoke out on idle before warm. Since I hadn't started the car all weekend, and the blue quickly stopped, I didn't think anything of this..... But this morning, I noticed blue smoke out of the exhaust as I put my foot down. The car is a 1972 2000tc that I have just bought (with a so called rebuilt engine). The car doesn't smoke on idle, but only when you put your foot down.

Any ideas guys... sounds like valve seals to me, is this usual, or could it be something else? I put a new flame trap in the other day and made sure that the other breather filter was clean, as a matter of course...
My past understanding of these engines, was that they didn't really suffer from valve seal problems.
Also having bought the car from a specialist in p6s, whats my come back if the car needs work, bearing in mind that the engine was advertised as having been rebuilt and does look like it has been apart.

Thanks for you help and advice
 
A good test for valve seals is to let up on the accelerator at speed for a second or two and then hit the pedal again. A puff of blue smoke will indicate oil being sucked by the seals with the throttle closed. Blue smoke on normal acceleration is usually oil blowing by the piston rings.......not a good rebuild, I would guess.
But do make sure you haven't overfilled the oil. I have had engines which would quickly burn a quart off, and then keep a level.
 
Certainly sounds like bores/rings to me. How old is the rebuild? Perhaps the bores weren't properly honed or the rings installed incorrectly. Try a dry then wet compression test.
 
Turned out to be just over full with oil. The marks on the dipstick seem very misleading. Drained off a litre of 20w50 and it stopped smoking.
Just gave it an oil change (seemed that a lot more than 5.5 litres of oil came out on draining) and filled it with 5.5 litres. Haven't checked the dipstick, but will do later and I will then use this as the top up measure in future.
Thanks for the advice
 
Hope that you changed the filter as well, because the capacity is 8 pints (4.5 litres) without changing the filter and 9 pints (5.0 litres) if you change the filter - Hence, 5.5 litres still sounds too much to me.
Still worth carrying out a compression test to satisfy your own mind re: the engine rebuild.
Glad that you're smoking problem has been cured tho'.
Regards, John,
 
:) I did and always do change the filter with the oil. I have the oil cooler as well and my workshop manual tells me that the 2000tc with a filter change is 5.5 litres.
 
Well the engine has exactly 5.5 litres in it and the dipstick is showing just under the low...... This is with leaving the oil to drain down over night
 
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