Hi all,



I'm doing up a 12a series II which I've recently purchased for next to nothing. The engine seems to idle and run fine and pulls pretty hard but it smokes like crazy once up to operating temp. This engine had been sitting for quite some time previous to me getting hold of it, my question is: what do you think is causing the smoke? Apex seals dried up? and is there any tricks to stop it from smoking save having to rebuild it?



Any advice appreciated



Regards

Marc

 

If the smoke is black, its fuel and likely some sort of tuning issue. Timing, carb jetting, etc.



If its white and dissipates quickly its coolant/water and one of the coolant seals is toast.



It its white or has just a slight tint of blue and it lingers until it eventually blows away then its oil. That would be bad oil control rings. Either the o-rings are dry and flat, the housing or the metal ring itself wore badly and leak, or there was some porting on that motor and it cut into the oil control ring path.



White smoke = rebuild

 

Or the rotor gear could of walked out and scuffed the plate, the scratches will make it impossible for the control rings to seal, if its oil smoke



Rebuild

 

I just tore down a motor with a similar problem. It ingested a worm gear hose clamp and punctured the rotor, made a nice smoke screen! Ran great other than the smoke.