Onan propane generator off season maintenance

[Horizonchase]

I have taken steps to winterize my motorhome but what should I do with the propane generator? After the MH sat for a month we took it out for a long ride and fired up the genny under a load and ran it for about 15 minutes. Is that all that I should do? I did the same thing last year and it runs fine without any problems ( so far) but I read of other folks having no start issues and I want to be a little more proactive than what I am now doing. Please advise me on the proper caring of our generator. BTW, the oil was checked & changed 3,000 miles ago. Should I have done another change at the end of the season?

[mel s]

Originally Posted by Horizonchase

I have taken steps to winterize my motorhome but what should I do with the propane generator? After the MH sat for a month we took it out for a long ride and fired up the genny under a load and ran it for about 15 minutes. Is that all that I should do? I did the same thing last year and it runs fine without any problems ( so far) but I read of other folks having no start issues and I want to be a little more proactive than what I am now doing. Please advise me on the proper caring of our generator. BTW, the oil was checked & changed 3,000 miles ago. Should I have done another change at the end of the season?

Horizonchase
My genrator is a 6.3kw Onan LP.....(although it is 17 years old it has been used less than 400 hours).
I seldom exercised my generator, but I will NOT make that mistake again.

I recently diagnosed and corrected a "starts but will not run when switch is released" problem.

I cleaned the "slip rings" of the rotor, checked resistance of the rotor coils, checked the operation of the control board, the oil pressure switch, and the stop relay...and replaced the bad voltage regulator......(PLUS, in mid project, I had to order a new "starter drive" and repair the starter because I ruined it with the repeated attempted starts necessary for diagnosis).

The complete DIY generator repair project took me 6 weeks and cost me nearly $300.

That repair would have not been possible without the "trouble shooting" and "technical advice" of Flight Systems: Generator & RV Controls | Engine Monitors | Idle Limiter | Repair & Rebuilding Services

I suggest that you obtain a owners manual for your specific generator and follow the recommended "exercising" and "oil change intervals".

Mel
'96 Safari Sahara

[sswilson]

Originally Posted by Horizonchase

I have taken steps to winterize my motorhome but what should I do with the propane generator? After the MH sat for a month we took it out for a long ride and fired up the genny under a load and ran it for about 15 minutes. Is that all that I should do? I did the same thing last year and it runs fine without any problems ( so far) but I read of other folks having no start issues and I want to be a little more proactive than what I am now doing. Please advise me on the proper caring of our generator. BTW, the oil was checked & changed 3,000 miles ago. Should I have done another change at the end of the season?

I start and run mine under load for about 1 hour/month during storage. The WORST thing you can do with these generators is to start or stop them while under load. Always warm up before applying load and remove load before shutting down. If done wrong, the generator is straining to produce the required power with low or reducing RPMs. I had to replace a regulator and they are not cheap.

[mhs4771]

Propane does have the Varnish problems as Gasoline engines, but when I asked the Onan Rep at a Rally he still suggested running it for 30 to 60 minutes at least every few months to keep the generator armature and contacts clean. Sitting too long and they can oxidize and loose contact or at least have high resistance which will effects it's ability to produce AC power.

[Lovin2Camp]

Hey MHS
Propane has NO Varnish Properties, which I am assuming you meant to type....

[mel s]

Originally Posted by Lovin2Camp

Hey MHS
Propane has NO Varnish Properties, which I am assuming you meant to type....

Lovin2Camp
You are correct that propane has NO Varnish Properties, (it can be stored for long periods, and then used, with no danger of "gumming up" the carburetor/engine of the genset).

As MHS said, sitting too long without being exercised can/will allow oxidation of the copper "split rings" of the rotor, (on which the brushes ride), creating high resistance.
If that resistance is to high it can cause the voltage regulator to fail....

BTW, a bad voltage regulator is only one of the many causes of the dreaded "starts but will not run when start switch is released" condition....(A bad oil pressure switch or a bad stop relay are 2 other causes).

Mel
'96 Safari, 6.3kw LP Onan

[Cooperhawk]

My problem always was the points would become corroded over the Winter. I usually had to clean them to get it to run in the Spring. I also had a condenser give up the ghost one year.

Running the genset once or twice over the Winter solved that problem.

[Hooligan]

Oil change is a least once a year, or 150 hours operating. (For NHM propane) - I do my change at the start of the season but also have low annual hours. Some recommend putting in fresh oil before storing. Exercising the genny is important!!!

Good information here: RV Tech Library - Generator Topics

[Horizonchase]

Originally Posted by mel stuplich

Horizonchase
My genrator is a 6.3kw Onan LP.....(although it is 17 years old it has been used less than 400 hours).
I seldom exercised my generator, but I will NOT make that mistake again.

I recently diagnosed and corrected a "starts but will not run when switch is released" problem.

I cleaned the "slip rings" of the rotor, checked resistance of the rotor coils, checked the operation of the control board, the oil pressure switch, and the stop relay...and replaced the bad voltage regulator......(PLUS, in mid project, I had to order a new "starter drive" and repair the starter because I ruined it with the repeated attempted starts necessary for diagnosis).

The complete DIY generator repair project took me 6 weeks and cost me nearly $300.

That repair would have not been possible without the "trouble shooting" and "technical advice" of Flight Systems: Generator & RV Controls | Engine Monitors | Idle Limiter | Repair & Rebuilding Services

I suggest that you obtain a owners manual for your specific generator and follow the recommended "exercising" and "oil change intervals".

Mel
'96 Safari Sahara

Thanks for pinpointing what could be the specific problems that people have had with their generators. I knew that they were having some problems but I didn't understand the cause of them.

[wa8yxm]

Fuel type does not matter. Run Generator 1/2 hour under at least 1/2 load every month, or if you really want to continue the theme 1/2 month but once a month is ok, I do mine on the 1st usually.

Or this month on the last 3 days.

But I also woke up 800 miles north of where I am not 3 days ago. (800 miles including 100 of "Mountain type" driving (Foothills) in 48 hours, best time I've made in years).

(Turns out I had a medical problem.. Doctor fixed it, THANKS DOC).

Nice and warm here.