Thanks for the advice! .... ...Ahh Yes 4-stroke - I should have mentioned that
- And Yes: I adjusted the float valve - because the carb was over flooding - it's tricky to get it right but is now is OK.
- Rich fuel mix – well I know the sound the engine makes when the choke is accidentally on and the engine struggled a tiny bit like that – so I presumed (in error?) perhaps the mix was a bit rich.
- Carb: The idle circuit – There is a "Pilot Jet" which in some service manuals
shows a "Bushing" blocking the tube and in other manuals
no bushing – I’m not sure what this jet does: But at some point I ( experimentally) blocked the tube with a grub screw and the engine worked perfectly – so I left it like that until just recently – might put it back.
The spark plug
was black sooty - not so much oily - But I need to confirm.
The Sludge was definitely oil it felt clingy and slimy like engine oil does.
OK lots of good advice, if it's still hemorrhaging oil after a long hard run, i try an compression test - well - I have a leak down tester.