LP Generator not putting out voltage? HELP!!!

[ClydesdaleKevin]

What the heck?



It is raining cats and dogs here in Utah, and cold.  So the batteries didn't charge all the way up from the solar panels today.  The battery bank got down to 12.2 volts, so I turned on the generator.

It started right up and runs great.  And then I plugged the shore cord into the generator outlet...and nada!

The fuse in the generator is fine, and it doesn't matter which way I have the two side breakers switched too...no power to the outlet!

If I plug the coach shore power cord into the inverter plug I installed, everything works great, so it isn't any of the interior coach breakers.

Right now I'm running the diesel engine to charge the coach batteries, and running off inverter power (with the converter switched off). 

The generator is an Onan NHM 6500 watt LPG, circa 1995.

The coach came with two manuals, but no troubleshooting guide in EITHER manual.

HELP!!!

Kev

[joanfenn]

https://www.bing.com/videos/search?q=onan+6500+generator+troubleshooting+guide&qpvt=onan+6500+generator+troubleshooting+guide&view=detail&mid=1CD53465660E70A84A371CD53465660E70A84A37&&FORM=VRDGAR

[ClydesdaleKevin]

https://www.bing.com/videos/search?q=onan+6500+generator+troubleshooting+guide&qpvt=onan+6500+generator+troubleshooting+guide&view=detail&mid=1CD53465660E70A84A371CD53465660E70A84A37&&FORM=VRDGAR

Thanks Joan.  Those are the three things I knew to check, and checked them, and still no power.  I'll check them again in the morning when I have some daylight...and hopefully a break from the rain.  Hopefully it IS something that simple, and it isn't an expensive fix, or a complicated fix like replacing a breaker in the generator itself.  That would suck, especially with the HUGE puddle right under where the generator is from all this rain.

Kev

[DaveVA78Chieftain]

All the manuals for NHM Generator are in the documents area.

[ClydesdaleKevin]

So until I figure this out, does anyone know if it is okay to run our Cummings diesel at idle for an hour or so once in a while to top off the batteries?  Rick?

Kev

[Rickf1985]

I answered in the gear box about idling the engine and yes you can but try to keep it under and hour without going up there and revving up to around 1200 and holding it there for a few minutes to clear out unburned fuel. Diesels run very efficient at idle and therefor run cold. The air fuel ratio for a diesel engine at idle is 160:1! Compare that to a gasoline engine at stoichiometric ratio of 14.7:1. If you have to run the diesel engine for an extended time get a stick to hold the throttle at around 1,000 to 1,200 rpm.


As far as the generator, when you started it did you hold the start switch for a few seconds after it started? This is required on a lot of sets to excite the winding and get power going.

[Froggy1936]

Hi Kev. On my Honda Generator Twice i had to replace the built in voyage regulator, One time my fault (allowing it to shut down under a load) They try to supply 110 V even as they die out. The second time was from the squirrels eating insulation off the wiring in the control box . That time i was away and did not have shop available, So i replaced it @ Harbor Freight The new one has breaker,for either problem . Disassembly and repaired after i got back home ! Its not really all that hard to do, Frank

[tmsnyder]

I think Flight Systems has the best troubleshooting guide out there:


https://www.flightsystems.com/troubleshooting/

[ClydesdaleKevin]

Thanks guys!  I did indeed hold the start button down until it started fully and let it run for a few minutes before checking the voltage output.

Today I checked voltage to the outlet...nada.

So I checked voltage to the junction box where the wires come out of the generator...nada.

Then I pulled the front cover off the switch panel on the generator and tested voltage going to the breakers...nada.

I'm stumped.  This thing runs great and only has around 80 hours on it.  Could it be something like the control board or voltage regulator?  Is there some sort of solenoid that goes from the control board to the wires that feed the coach?

Kev

[ClydesdaleKevin]

I think Flight Systems has the best troubleshooting guide out there:


https://www.flightsystems.com/troubleshooting/

Thanks Tmsnyder!  Sounds like it might not be field flashing.  It started raining again, but when it clears up I'll check the voltage at the pins mentioned in the troubleshooting guide.

Kev

[Froggy1936]

Follow the TS manual to the letter, (the one mentioned by tmsnyder looks very good and easy
to follow ) And always remember  Reddy Kilowatt is not your friend , Finding 220V sitting in a puddle can come as quite a shock ! If possible before starting make sure brushes are not stuck . Frank happy hunting !