170VAC coming from my Onan generator

Thank you all for the great advice. I wish there were "like" buttons for posts. You all are great.
I am also contacting Flight Systems soon.

Voltage regulator located behind start/stop panel

Parts manual See pages 46-47

Note that 170v is standard AC sinusoidal ‘peak’ voltage that relates to 120v which is RMS... Perhaps check your instrument settings...

3 tons

https://onan.xmsi.net/965-0530%20Onan%20BGE%20BGEL%20(spec%20A-C)%20RV%20Genset%20Service%20manual%20(05-1986).pdf

Page 87. Doug

transformer is incorrectly
connected or defective.

This is the "regulator". Doug

Voltage Regula ti ng Transformer
The voltage regulating transformer helps to provide
stable generator output voltage under varying load
conditions. Voltage transformers are constructed
with two primary windings and a single secondary
winding. Each primarywinding (Hl-H2and H3-H4) is
connected in series with one of the generator AC
output windings. The transformer secondary winding
is connected in series with the field current circuit.
Taps on the secondary allow for field current
adjustments.
The voltage regulating transformer mounts on the outside of the generator housing and is enclosed with a
special cover. The cover must be in place during operation for transformer cooling.

Before calling Flight Systems, get as much information a you can. Exact model and spec number, locate the regulator and get exact numbers off it. Take readings and have them available.
Did you see the linkage to the throttle moving? With genset off, try moving the linkage by hand. Doesn't take much pressure.

This might be comparing apples to oranges, but on my Generac 5500 I had a similar problem. I had driven through a very humid and rainy day. When we pulled in for the night (boondocking) I fired up the generator to make dinner. I always take a glance at the Kill-o-watt to see the output of the gen. It was showing 155 volts.

Long story short, I removed the control panel cover and found a buildup of years of dirt on the regulator module. It almost covered the connection. That plus the excessive humidity was causing a short in the connector. After thoroughly cleaning, fired up the generator and everything was fine.

Gjac wrote:
If the engine governor/regulator is high to cause 170 v you would hear it reving high. First before you take it in, plug your volt meter into your house circuit and see that it reads 120 v or so just to verify meter. Is it reving high? Did you verify your meter is good? There is a company called Flight Systems that have helped me in the past with my Genset and other systems. If you call them 717-590-7330 and describe your problem they can help you fix it. They also have a troubleshooting guide for your genset on line.

My meter is accurate and the genset is not revving high.
Thanks for the Flight Systems tip.

If the engine governor/regulator is high to cause 170 v you would hear it reving high. First before you take it in, plug your volt meter into your house circuit and see that it reads 120 v or so just to verify meter. Is it reving high? Did you verify your meter is good? There is a company called Flight Systems that have helped me in the past with my Genset and other systems. If you call them 717-590-7330 and describe your problem they can help you fix it. They also have a troubleshooting guide for your genset on line.

theoldwizard1 wrote:
Under some circumstances digital volt meters can read "ghost voltage". This typically occurs when there is no voltage at all on the probes but there is voltage in nearby wires. Ghost voltage is usually unreasonably high.

Best solution is to use a very low wattage light bulb across the points you want to test and the meter leads across that. If the high voltage is real it may blow the bulb so be careful !

Exactly correct!