ONAN ELECTRIC PLANT

heres another plant that i would like some help with. it's tag reads ONAN ELECTRIC PLANT, model# 5CW-3P, spec# 1A, serial# 103B489767, A.C. volts 115-230, k.v.a. 5, watts 5000, P.F. 1, amps. 43.5-21.8, cycles 60, phase 1, D.C. volts,amps,watts:these spaces are blank., Generator #403039, gen.data no. 5CW3C1A, R.P.M. 1800, use 12 volt battery, manufactured by D.W. ONAN & SONS,INC., Minneapolis,Minnesota U.S.A., bottom left corner of tag has:99-115K, bottom right corner made in U.S.A.,

as with the others i have listed i would like to know what year this one was made in and possibly how many h.p. it has, i can describe it as 2 cyl.,gas,magneto fired,hand crank or electric start,has oil filter,aluminum downdraft ZENITH carb.,air cooled,

i believe that the model# and the fact that it says electric plant and not just generator and the fact that it says D.W. ONAN & SONS instead of just ONAN will be good indicators to the right person as to when this was made and how many horses:remember 2 CYLINDER and only 5000 watts!

thankyou in advance for ANY help you can be on this and have a good night...

Onan dating prior to 1967 is as follows: First one or two letters is the month. Second letter is the last number of the year. The letter indicates the decade,

A=1940, B=1950, C=1960 The last five or six numbers are actual S/N. This system only dates back to the forties, prior to that Onan used a decimal point after the first two or three numbers.I think the numbers work the same way, but the year is in the thirties. I'm not sure if this is correct, but it seems right. After 1967, the first two are the month, the second two are the year.

A 10 KW version of this generator was used in Mr. Softee Ice Crean Trucks...The 5 Kw and 10 Kw machines were identical in size and appearance...Onan used a standard of 1 HP per 5oo watts, hence a 5 KW machine would have a 10 HP engine...The 10 KW machines used by Mr. Softee were rated at 20 HP...