Hello, this is my first posts to the forum but I have been reading, admiring and learing by reading here sense Ive started machining.
This is my 2nd IC build. 400 hours work over the last 7 months and about 400 parts finally came to life and I got it running reliable yesterday.
It currently runs on glow fuel but I would like to eventually convert it to gas and fit a CDI ignition.
I dont have any build pics, just pics of the parts as they where completed.
The engine is a 120cc 4 cylinder 4 stroke. The plans are from Germany. I did a fare amount of modifying and redesigning the parts. More to experiment then to fix problems. Also to convert all the metric dimensions to imperial as thats the only tooling I have.
Here is where I found the plans. They have many aero motors and that is my real passion.
2nd test run 600 rpm idle 5200 rpm at 3/4 throttle.
The pistons and rods are 2024, intake and exhaust is 304, cast iron cylinder sleeves, valves are 416 and bronze on the valve cages and bushings.
The exhaust tubes where filled with lead bent using a custom made bender then the lead was melted out.
I made a custom valve seat cutter that I learned about from this forum and it worked perfect, only a light lapping was needed.
The valve springs are wound on the lathe using a technique I found online. They are then stress relived in a toaster oven. They where easy to make but tricky to make all the same.
The rods have needle bearings in the big end and bronze bushings in the other.
The roller rocker arms are 6061 with hardened W1 rollers and roller shafts.