I use a fuel called 'cool power' 15 %. Not sure on what lubricant. I obvioulsy need to examine it further but whilst stuck at work i thought id do a bit of back ground. I took the glow plug out (renewed it)and it was still stuck - thats why i had to take the back plate off and give it a nudge. I wondered if there was any other obvious reasons for a lack of power other than a ruined piston ring etc. Also, is excessive white smoke symptomatic of a knackered ring/sleeve. The engine is a tt39.