We started running this JKSON in 2013 to drive an Utterpower PMG for off-grid service. It has given relatively trouble free service so far. An oil change every 250 hours, the valve gear gets oiled before each run, it gets wiped down once in a while, other than that, it just gets run. The engine lives outside under a shed roof here on the Canadian we(s)t coast.
A few days ago, pulled the head for a 1000 hour decoke and to check on things generally.
Found carbon build up to be very little in the head and comet. The exhaust valve and port had most build up. I pulled out the valves and gave them a clean-up and light lapping. Noticed that the piston head had an area of no carbon and some light pitting. Every so often, I spray about 1 litre of water into the intake at high loading, this may account for little carbon and the pitting. A visual check showed no discernible wear in in the bore, some cross hatching was still visible and no ridge can be felt at top of ring travel.
When I first started running this engine, I knew next to nothing except to pull it down, clean out the sand, reassemble, and run. Over the hours and years, much has been learned from the expert advise and sometimes questions and mistakes from other amateurs like myself here on the forum. I kept this in mind when putting things back together.
A major item was to check bump clearance! Before I pulled the cylinder off, The bump measured .120" .No wonder it was hard (read nearly impossible) to hand start in cooler weather. What a difference in starting with the bump set at .075". Now this JKSON starts as easily as my Dursley 6/1.
One reason for the large clearance was several thick cylinder base gaskets. Another problem, the wet sleeve protrusion above the deck was out of tolerance......too proud by about 7 thou. That was remedied with one of my hand operated milling machines.........patient draw filing did the trick to bring the protrusion into limits.......made the head gasket seal the water passages better as well!
Just for grins, visually checked the crank journal, shiny no scratches. Rod bearing clearance was in tolerance.
Drained the sump, wiped it out with a quart of diesel, changed the aftermarket filter, oiled it up and it is ready for another 1000.....I hope many 1000s!
Thank you all for the help, advise, and assistance. The readily available wisdom and information here makes things lots easier.
Cheers,
Hugh
BTW, I still have that SR2 to give away. Found some time to reassemble it, so might be easier for one of you to get it.