generator shutting down

[Gary Winzenburger]

Last week, I decided to shut everything down including both banks of batteries, inverter/charger and let the coach sit while we were gone for the weekend. This morning, I tried to start the generator - low battery. So, I hit the battery, boost switch on the driver's console and it started. It ran for about 30 seconds and then quit after something tryed to start somewhere on the passenger side about half way back. I tried this same scenerio 3 times and it did the same thing. It started after using the battery boost toggle and then quits after about 30 seconds of running after trying to start something, which buzzes for a few seconds until it shuts down.  

I thought I had everything shut down, so I'm puzzled what's causing the generator to shut down after trying to start something.  I finally plugged the shoreline in and everything seems to be working including the inverter/charger. The generator starts and runs. I routinely check and maintain the batteries, so I don't know exactly what's going on. The system panel shows everything fine. Any ideas?
Thanks, Gary

[Bill Sprague]

Gary,

I'm doing some guessing here.  But, I have a hunch.  It is that the batteries that start both the engine and genset are too dead.

The 30 seconds is a normal "warm up time".  At the end of the 30 seconds, the transfer switch engages and the genset should power the coach.   At this point it is sensing one of several faults that cause shutdown.

The manual ( http://www.cumminsonan.com/www/pdf/manuals/981-0161.pdf ) has instructions on how to read the flashing light on the switch to determine the fault.  A few of them suggest when adding even a small load to very dead start batteries the genset senses an anomaly and shuts down.  

After looking at the book, can you post what the fault code is?

[Edward Buker]

You knew that the starting batteries were very low in charge. You boosted to make the start and then released the boost that leaves the genset running on low battery voltage. I think some load is being added after 30 seconds to the starting batteries and the voltage level drops low enough to kill the generator engine monitoring system and it shuts down. I say this because at times if I have the generator running and I crank the main engine it will kill the generator. If I use the boost while cranking the main engine the generator continues to run. Bill's comment may be on the mark, but I do not see how the transfer switch would add any DC load to the starting battery bank. There might be something else pulling a load after some lag time, you may have to find exactly where the noise comes from to know for sure.....maybe a hydo hot? The good news is that I think this is pretty normal and holding the boost down for several minutes while this initial charging and the added load kicks in may just eliminate the issue.

later Ed

[Gary Winzenburger]

Bill, I didn't think about looking at the switch on the genset itself. I was inside the coach. After about 4 hours with the shoreline hooked up, everything is in the green on the CMP-10 panel, but I'm kind of concerned that the Amps DC House indicator is jumping all over the place from 0 to 26 AMPs. I'll let things go a little longer and see if it settles down. The Heartface shows 30 AMP's with 13-15 Volts with the inverter/charger on. I've done the same thing with shutting everything down and leaving if for longer than a weekend with everything starting, so I'm wondering where the problem might be. A real head scatcher! Ed, I hope you're right!
Thanks for all your help!
Gary

[Jeff Watt]

I'll join this thread, although I don't have any solutions; more questions actually.

In early September on my way to the BAC to the future rally, I was running my generator on a hot day. Sitting in a Walmart it shut itself down - code said overheat and service required. No loss of fluid and oil pressure good. Let it sit for a few hours and it started up and ran. It also started and ran well the next morning.

Long story short, I assumed all was well, BUT one shouldn't assume! Coming home last Sunday, i tried to start it (by coincidence the same Walmart) and it will not run for more than a few seconds - 20 tops. Fault code shows service required and secondary fault is 13 which is low output voltage.

I am puzzled as it dies before I think it can produce any voltage. The manual says to shut off the breaker and try - no difference. It seems to just stop as if running out of fuel (lots there). Batteries good.

Read a previous post started by Dave Cunningham; I contacted Dave and he suggested (as mentioned by Bill) to try the boost. While the genset turns over faster - I think there may also be an issue here with starting voltage - it does not stay running even if the boost is held down.

While not necessary, I have even tried the priming procedure and while it may run for a couple of seconds longer, there is no fundamental difference.

I have an appointment for a coach service and I am going to have the tech see if there is anything obvious. If all else fails I guess I have to take it to the cummins/onan service in Winnipeg. I do note that the motor is a Kubota and as i have 3 Kubota tractors, i may give my Kubota dealer a call - the Beaver will look odd in their  yard sitting  beside the combines, tractors etc.

Thanks,

Jeff

[Steve Huber Co-Admin]

Jeff,
I had same symptoms on a 10K  (Izuzu powered), Ran only a short time and threw a 13 code. I serviced the unit; oil, oil filter and fuel filter but no change. Found that the fuel pump was failing. Apparently had enough fuel to start but not enough to get RPM  high enough to generate proper voltage before shutting down for lack of fuel. BTW, early symptoms was that it would run but not hold load.
Steve

[Edward Buker]

Jeff,

Not sure of this but the belts that drives the fan have been an issue with material breaking down and slipping on some gensets. That gave me an overheat condition. The funny thing is that there is no squeal associated with the slipping belt. I only had a little over 200 hours but t was an age issue at 10 years old. The belt was worn so that the V width was much reduced from what the new one was. This was from wear and the friction available did not drive the fan at speed. Replaced the belt, tensioned it and all is well. You may have multiple issues going on...

later Ed

[Gary Winzenburger]

After about 8 hours with the shoreline attached (30AMP), the CMP monitor is showing green, except for the Volts DC House batteries flashing red indicating 25.5 volts. The Heartface is showing DC volts at 130 and amps 20. Anything I should be concerned with and/or watching?

Thanks for all your help!!
Gary

[Edward Buker]

If you have a voltmeter measure at the battery bank with the charging system on. Should be about 13.8V. If that is so then ignore the CMP. Check the water level while you are at it. I presume the 130 was 13.0V.

Later Ed

[Jeff Watt]

Ed, Steve,

Thanks for the thoughts. The belt may be an issue as it is 6+ years old and the genset has 176 hours. May have it replaced anyway. If it is the fuel pump, then that will be a relatively easy solution. Hopefully it can be resolved.

Garry, I didnt mean to hijack your post - should have started another or added to Dave cunningham's.

Jeff

[Keith Oliver]

Jeff:

At 176 hours, your genset has not even been broken in yet.  I doubt anything needs replacement due to wear.  If you have cooked it somehow, maybe it is gone, otherwise, have a look at it and see how new it looks.  I know of gensets in commercial duty that run for 30000 hours before any mechanical work and get inspected no more than annually for such things as belts and hoses.  If run for a year, continuaously, (24x365)  8760 hours is the service interval.

[Gary Winzenburger]

No problem Jeff, I'm learing a lot from their comments!
Gary