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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 rpm loss sensor on my generac generator 20kw, I

Customer Question

I have a rpm loss sensor on my generac generator 20kw
JA: What's the make and model of the generator? And can you guesstimate how old it is?
Customer: I think it's about 6 or 7 years old generac 20kw is all I reall know
JA: Do you plan on doing the work yourself?
Customer: If possible yes; out of power; daughter not feeling well needs an asthma treatment
JA: Anything else we should know to help you best?
Customer: It was working earlier today but turned it off; to save on propane; last night didn't start and figured out it was dead battery; took battery off a spare car and that got the stater going and then it turned; ran for like 15 hours no problem
Submitted: 1 month ago.
Category: Small Engine
Expert:  Hank F. replied 1 month ago.
Hello, my name is ***** ***** I am going to assist you with this.
Try to start the unit manually.
Will it start and run in manual?
If not, what are the model and serial number of the unit?
Customer: replied 1 month ago.
In the midst of traveling right now, but can be back quickly. To check the serial and model. It does not start on Manuel or on auto
When u try to start on either position
Message reads rpm sensor loss
Customer: replied 1 month ago.
It's a generac 20kw system
Customer: replied 1 month ago.
Model:(###) ###-####(###) ###-####serial
Home now
Expert:  Hank F. replied 1 month ago.


Right beside the oil cooler is a bolt that has a wire number 18 connected to it.

Set your meter to VAC, and connect one lead to that bolt, and the other lead to a good ground.

Set the switch to MANUAL.

What reading does it give before the unit shuts down?

Expert:  Hank F. replied 1 month ago.

Have you tested this yet?