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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 13581
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
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I have a 12.5 Onan diesel generator, which starts, runs for

Customer Question

I have a 12.5 Onan diesel generator, which starts, runs for 30 seconds to 2 minutes, then shuts off. Runs great while running, no missing, no rough idle. will not take a load. just shuts off. i took it into Stewart Stevenson 2x, and they determined there were sensors to be replaced and a new radiator. Went through the entire system, and released. Picked it up the second time, and does the exact same thing. It still stalls randomly, and I cannot count on it. They said they would just have to rebuild the entire unit, as they cannot determine the problem. Extremely frustrated. The unit has been excellent until now. It has new water pump, radiator, sensors, etc, and lightly smokes for 30 seconds at cold start. does not smoke after warm up. I think just throwing more parts hoping it would work is not getting the job done. It does not need rebuilt. We are looking for help, as we took the unit to an authorized dealer, spent $3k on repairs and have no answers. Can anyone help me figure this out?
Submitted: 2 years ago.
Category: Small Engine
Expert:  Hank F. replied 2 years ago.
My name is ***** ***** I am going to assist you with this.
What is the full model number of the genset, exactly as it appears on the data label?