Thanks Jan...I am enjoying it!
Update: First, I want to say that I am absolutely sure this engine would have ran on "steam" power, right out of the box,... However...it was not in a high state of tune.
Before adjusting anything, I just oiled it and connected to my aquarium pump at 2.32 PSI...it would "try" a little but not run on such low PSI
I did notice the power pulse was much stronger from the outboard cylinder and the "closer" that I got the crank pins to "true" 180 deg from each other the more the inboard cylinder power started to equal the outboard cylinder power, so I have answered my own question about that!
Next I trued both cylinders to be square to the Flywheel axle and with a bit more oil and gentle adjustments so as not to break any solder joints she slowly started to run on the 2.32 PSI and after running for a few minutes even started to pick up speed!
I am quite thrilled with the D12 running on this low PSI because it is doing it with "Stock" springs!....I had to drop down to a soft "ink pen spring" to get my D5 to run on 2.32 PSI
I had forgotten just how much smoother Twin Cylinder engines run, she is whisper quiet on aquarium pump power!
I am only about half done with my tune, the Rods are now square to the Flywheel axle(looking down from above the engine)
But if you view the L shape parts the Cylinders mount to from the front firebox door side...those are a little out of square to.
Tomorrow I am going to partially dissassemble the engine and get the "timing" to perfect 180 deg...also my inboard oil cup is flowing MUCH less oil so I want to inspect if it is slightly blocked by powder coat or if the outboard bearing hole is just larger.
Current state of tune the D12 will run at about 85% of full throttle on my aquarium pump, my best running Wilesco will run with the aquarium pump set at only 40% so I Can measure if I am making improvement.
Neat little engine, and I am loving "tinkering" with it to get it to run on such low PSI.
Photo: there is oil everywhere and the chimney is removed so I can wrench without bumping it off...so not a beauty photo...BUT...it is running in photo on aquarium pump, the spokes are transparent at this speed and nice and quiet!
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