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Hank F.
Hank F., RV tech - emphasis on gensets
Category: RV
Satisfied Customers: 15281
Experience:  RV tech since the beginning of the millenium.
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Generator cranks and idles very high, turn AC on ,generator

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Generator cranks and idles very high, turn AC on ,generator almost stalls out. The breaker switch inside of the RV will throw, the AC shuts off, the generator again will idle very high. I have an Onan 4000 genset the model number is ***** thank you
JA: Is the check engine light on? Does the car stall at idle or when driving?
Customer: I am referring to the generator and rooftop ac in my Winnebago rv.
JA: What year is your 4000?
Customer: 1996
JA: Are you fixing your 4000 yourself? What have you tried so far?
Customer: Nothing yet , just started this.
JA: Anything else you want the mechanic to know before I connect you?
Customer: Will the serial number of the generator be of help?
Hello, my name is ***** ***** I am going to assist you with this.
I need you to turn off the breaker at the genset, remove the control panel, and connect a voltmeter to the back of the circuit breaker, on the terminal farthest away from you, and start the genset.
How much voltage is being produced?
Now set the meter to read frequency.
What frequency is it running at?
Hank F. and 2 other RV Specialists are ready to help you
Customer: replied 2 months ago.
On my way to get the voltmeter.


I have the drawings uploaded.

The first page is the parts list. Compare it to what you have, and let me know which parts need to be replaced.

The second page shows the 2 adjustments I was talking about. The sensitivity is the screw you were looking for, and the speed adjustment is a nut.

Test both to make sure they will adjust, and are not froze up. If they are froze up, we will need to replace, them, also.

Click here to download the drawings.

Just reply to me here to let me know what we need.

Customer: replied 2 months ago.
Finally got the file to open ! The end of part 7 is what I was trying to describe to you as being broken . I check the the parts you circled tomorrow . Thanks a lot Hank . I will be in touch,

That part is listed as obsolete, and is no longer available.

You might could try some internet searches, but you are going to be hard pressed to find one, short of running in to someone who has a genset that they are scrapping.