Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Quote from: 70Rcode on January 28, 2020, 02:10:48 am

..... this rubber O-ringed engine series is really intended for short run, novelty duty cycles.....

Yes, in my opinion, and enjoy it for the very affordable little gem that it is.  Machine an IC engine from scratch sometime for maximum appreciation of what JIN provides us.

I submit to you that if set up right, these engines work fine for long runs.


I set one up for the slowest possible run. I had retarded the spark to top dead center, I put much softer springs on the governor weights or stretch the original springs and remove one of them. Removed the lower O-ring (this was well before Jin started shipping them with 1 O-ring). Massaged the piston and bore with Simichrome polish before re-assembly. about once an hour, I put a drop or two of high grade synthetic clock oil at the piston skirt end of the bore. When completely full of the fuel/oil mix (about 16 cc), I got a run nearly 5 hours long with no load. It was 4:56 to be precise. Even toward the end of the run the head temperature read out on a laser thermometer was never over 98 degrees and was 95-96 most of the time.


For details on the run see reply #9 on this page:
https://www.officeofsteamforum.com/general-discussion-scale-model-gas-engines-hit-miss-throttle-governed-non-compression-etc/2-hours-17-minutes-running-time-with-full-tank-(10-cc)-with-a-jin-m90/ 


Gil