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

Jim, if your displacer crank is at 12:00 o'clock, then your power piston crank would be at 3:00 o'clock, 90 degrees out of phase.

Hope that helps!

It´s just a plug to close the casting, after drilling the channel inbetween displacer and workpiston.

As part of my "Peanut - Rider" routine maintenance, I remove the plug and insert a pipe cleaner soaked
in meths to clean the passage out. Oil from the displacer piston bushing can accumulate in the passageway and reach the piston and cause problems. I normally clean and lubricate my engine before
each run especially after it has been sitting awhile.

I have a PM #13 that never would run. I got it a few years back from a relative. I wondered if it was assembled correctly, but oddly PM Research has no online (PDF etc) assembly or operating instruction . But they will send a hard copy of the instructions by mail for a few dollars.
Anyway, just to be sure, when looking from the perspective of displacer side (w/pin @ 12o’clock) .... the crank pin on the power piston (the graphite colored piston?) should be at 3 o’clock , not 9 o’clock.?

You are correct. Looking from the displacer side through the flywheel, the power piston crank pin should be at the 3:00 o'clock position and the power piston connecting rod should be fully extended with the piston skirt showing maximum exposure out of its cylinder, at the "bottom" of its stroke.

Perhaps I should add that the flywheel then rotates Counter-Clock-Wise (CCW) as seen from the displacer side, when set up in this fashion .... that is to say, the top of the flywheel moves toward the displacer, heat cap and flame. Also of note is that the flame should really be adjusted such that the very end of the heat cap does have flame engulfing it as well as the cylindrical sides of the heat cap, but the flames really shouldn't get too close to where the heat cap enters the body where the cooling fins are located. The power piston should never get any oil of any kind, but the displacer shaft can use a very little, far less than a whole drop, very light grade of oil occasionally, right where it enters the guide bushing. All other mechanical motions, bearings, wrist pins & etc, should be oiled lightly and regularly.

I believe you to be absolutely correct Dennis .... the mechanics of the Stirling Cycle suggest it to be so!

Thanks to Jim (OP) and those who answered this thread I finally got the PM #13 to run, but only in short 10 second burst. I think this was the first time this PM Solar Engine #13 was even ran, and it looks like the original owner must have given up after they built it. The PM #13 is a basic pre-machined kit model (vaguely similar to the Op’s #7) that the “thinking man” assembles. https://www.pmmodelengines.com/shop/solar/solar-engines/solar-engine-13/
This is the only solar/stirlling engine I have, but I can see a lot of little areas where a novice could simply make an assembly mistake. I thus wonder why PM doesn't have better YouTube videos for their products, especially with the massive influx of cheaper Chinese engines flooding the marketplace.
So, anyone have advice on how to tweak any longer run times from these PM Solars ?
[apologies if I am mis-stepping into the original intent of this thread]

Jim, Do you think using a file on some pencil graphite to make powder will work?
How to you get the powdered graphite on to the pistons ?