Petter Harmonic

First public running of the 1936 16hp Petter Harmonic diesel engine. Only three survivors of the one hundred built are known to exist. The engine is first started on crankcase compression and then shifted to harmonic running. The exhaust length is still not quite right but she ran well at Easter for the first time on public display.

Category:

Science & Technology

Tags:

• petter
• stationary
• diesel
• engine
• harmonic
• museum
• two-stroke

[scotty2307]

If I understand this engine correctly than it is a two stroke design with exhaust tuned to provide scavenging to bring a fresh air charge in to the cylinder?

Does this design actually provide some power gain over a case pressurized system?

Would it hurt the engine to take some measurements of Amps vs. RPM running both ways? That could be interesting.

[semidiesel]

Correct.

It was certainly more powerful than a similarly sized crankcase compression two-stroke from the same company.

[Nec1228]

its got a great sound to it. how does it use crankcase compression to start?

[semidiesel]

There is a valve on the flywheel side operated by the small lever on the front. Lever up swops to crankcase compression along with a flap on the inlet (behind the engine) that switches in a read valve (in the flap). To changeover you need to throw the flap and lever at the same time.

[InflatablePlane]

WOW! Thats suprisingly silent and smooth for a 70 year old engine O_o! Awesome :D

[Nec1228]

cool