Os Fp 40/tank Needs To Be Cleaned?
 

Just bought a sig mark-2 with a OS FP 40 it had been sitting for about 6 or 8 years changed the glow plug and it started right up but then dies.I think the tank needs to be cleaned out Any ideas on how is the best way to do this?Real thick oil came out of the exhaust when the nose was held in the air.I asume that this was old castor after the fuel had evaporated.

Os Fp 40/tank Needs To Be Cleaned?
 

I'd just replace the tank and fuel lines, to start with. Cleaning it is fine, but the rubber seals and fuel lines are probably due for replacement.

Os Fp 40/tank Needs To Be Cleaned?
 

And the thick oil is not unusual for a two stroke. It can build up in the muffler and will pour out afterwards.