Author Topic: Witte CD-12... How slow can you go?  (Read 3203 times)


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Witte CD-12... How slow can you go?
« on: December 21, 2012, 01:17:54 AM »
I have a Witte CD-12 that is rated 12 HP @ 750 RPM.  The generator head is an ST-12 (1800 RPM 4 pole head) with a 13" pulley run off of the 32" engine flywheel.  There will be times when I don't need all 12HP (6KW) of power, and would like to slow the engine down for greater fuel efficiency. 
I have a 8.25" pulley that will fit on the generator.
Running it off of the 32" flywheel, would put the engine at approximately 464 RPM.
Assuming the oil pressure is where it needs to be (~30 lbs.) can I run the engine this slow, or will it cause problems with the engine?  Potential issues as I see them are poor lubrication (I'd think would be OK as long as there is oil pressure), fuel timing too advanced for the lower speed, increased bearing pressures.

Do you think any of these would be a problem at low speeds, or are there any other issues you can think of?

Thanks for any input.

1982 300SD, 1995 Suburban 6.5, 1994 F250, R170, Metro 6/ sold :( , Witte CD-12 ..... What else can I run on WVO?