[Milsurplus] Gilbert MRCA Event AAR - MEP-025 noise

[Kenneth G. Gordon]

On 30 Sep 2019 at 20:09, David Olean wrote:

> Be glad you don't have a Detroit Diesel 2-71 genset. I have a 30 KW 
> military unit. a PU-708G Marine Corps genset. It runs at 1800 RPM but 
> the air blower runs at a very high speed and sounds like a 707 taking 
> off in your backyard. The first weekend I ran it, the neighbors 600 ft 
> away complained. We could not sleep anywhere near it. The next year, we 
> built a building around it. That knocked down the noise, but it was 
> still loud. It is not running now. It needs an overhaul.  I do not miss 
> the noise. That high speed blower really whined out! It sure made good 
> power though. Solid 60 Hz all the time and voltage fluctuations were 
> about a volt or two from no load to full load. It ran 208 3 phase .
> 
> Dave K1WHS

Hello, David: Yes. I can imagine that was noisy!

I have had several military generators over the years. But mine were never more than 5 kW. 
The one I liked the best was a PU-286G for a radar set. 4 cylinder, 1800 RPM, 
thermo-syphon cooling system, remote start/stop, 120 VAC 1 phase 60 Hz and steady as a 
rock. Also quiet.

Then there was another 5 kW job which I don't have the number for. It also had a 4 cylinder 
engine, but turned at a steady 3600 RPM. Had a recoil-starter (rope), and was switchable 
120/1/60, 120/3/60, 120/240/1/60, 208/3/60. Had postive rotating valves and was very 
noisy. It was brand new when I got it, but it had been dropped on one end and the motor 
mounts were shot, and the impulse-magneto had been ruined. I fixed it and used it for a 
number of years for our local club's Field Day.

I got both through MARS many years ago. Both gone now.

Ken W7EKB