Total Generator Failure

[GDeen]

Tuga, if you kick off the output load breaker does it settle down? I had a similar problem last fall and it was a speed controller along with a attenuator adjustment for lack of a better description. Under load it would start chasing itself up and down with RPM and vibrate. The speed control and other adjustment cured it.

[merle&louise]

Gordon,

I am going to change the fuel pump since Lee's problem was identical to mine. It is 12 years old and as a preventative maintenance item I feel it needs to be replaced with a new one. If changing the fuel pump doesn't do the job I will have a generator repair shop try to adjust the speed controller as you suggested. Thanks for the help.

[Jon Wehrenberg]

I'm not saying the fuel pump is the culprit, but mine did what Tuga described and the fuel pump cured it. At the time someone mentioned the fuel pumps on the Kohler were a problem.

[GDeen]

Certainly the easiest quickest way to attempt a fix...

[merle&louise]

I ordered a Kohler fuel pump this morning. Should have it in about 2 weeks. I was glad to be able to obtain a factory part instead of an aftermarket. I know they cost a little more, but I always feel better with OEM parts.

Thanks for all of the help. Once again POG to the rescue!

[GDeen]

Might as well jump in with my own problem. Last weekend while dry camping at the OU FSU game, my generator shut down at 10:30 PM. It was very hot so I had been keeping an eye on temps and the voltage, etc. Even had the bus aired up to max height on level low to ensure good air flow under to the radiator. Let it cool down and it still would not re-start. Runs for a second and shuts down. Steve B was kind enough to take a call from me and we checked several things to no avail. Good coolant level, good connections on everything, checked some fuses, belt good, basically everything we could think of.

Nothing like spooling up all your tailgating stuff at midnight and moving to a remote lot. Ran the big engine on high idle and OTR all night. Next morning, a very generous gentleman walked all the way out to the edge of the overflow lot where we were parked and offered us an extra 50 amp spot. As is the case with most RV spots at big football programs, there is a long waiting list for the electrical spots.

I put in new fuel filter, new fuel pump in Dec, and had just changed the oil and filter ahead of the trip. Had about 25 hrs on the oil change and interestingly enough, while it was on the lift at Prevost 2 days before the problem, I took a close look at the radiator with a flashlight and it looked very clean. Temps would run up to 200+/-, and the high speed fan would kick in and drop water back down to 185 in short order. Pretty typical of the way it has always run for me.

Kohler 20 KW with Yanmar engine and 3525 hrs. Seems like some sort of a sensor or sender is bad. Spoke with Rick May and he is going to walk me through a few checks when I can get some time to run out to the barn.

Any other ideas?

Since this is a resource and it is always good to post results, I was able to fix the generator problem today. Was headed out to the barn this afternoon to start checking some of the sensing units under the assumption that I might have tripped an overheat condition, and they stayed open or closed. Was also going to start checking voltage to the control panel, etc.

Talked to Steve Bennett and he suggested I pull the front panel and look for an inline fuse that he recently had a problem with on another coach.

Pulled the panel apart and checked the fuse for continuity - no joy. Was an 8 am slow burn which I didn't have, but stuck a 10 amp in and we are back up and running! Buttoned up the front cover and will go back and replace with the proper slow burn fuse. Sometimes the littlest things can shut you down. Thanks for the suggestion Steve!

[merle&louise]

Gordon,

Glad you found your problem. It's nice when it is a simple fix. My gen has been running a little on the hot side (about 210) with 95 degree ambient temps this past weekend at LSU. My parking site has a 2X2 drain so the generator (in front of coach) is about 2" off of the concrete. Not exactly ideal conditions for running 4 compressors, Louise cooking, and all of our other tailgating crap. We have been tailgating in this spot for about 5 years and this is the first time the temps have gotten this high.

So I removed my radiator this afternoon and am bringing it to a radiator shop to have it cleaned and tested. I ran the generator with the radiator cap off and watched the anti-freeze/water moving around. It was not flowing, it was just moving around and bubbling a little. I did this to test the water pump and it looks to me like the water pump is not making the water FLOW at a good clip.

My next test will be to test the thermostat and see if it opens when sitting in a pot of boiling water. I may just change it out since I have a new spare.

If both the radiator and the thermostat pass mustard - I guess the only other culprit could be the WATER PUMP!

Any other thoughts or opinions will be appreciated!

[Danss]

Trade up Tuga! Its nothing several hundred thousand dollars won't cure!

[Jon Wehrenberg]

Tuga,

Unless the generator is hot and the thermostat is open it is unlikely you would have seen any vigorous flow when you looked in the radiator. Before condeming the water pump make sure the thermostat is functioning and the radiator has good flow.

I am assuming the radiator fan is pulling air.

[merle&louise]

Jon,

I removed the radiator and am bringing it to a shop this morning for a good cleaning and thorough testing. I also removed the thermostat last night and tested it in a pot of boiling water; it opened!

The exhaust air that comes out of the bottom of the generator compartment is strong, so I don't think it is an air movement problem.

When I get the radiator back from the shop, I will install it, fill with new anti-freeze and install a new thermostat and then see what happens.

I remember back when I had my Bertram 38' w/Cummins diesels, I removed the radiator (cold) and started the engine. When the thermostat opened there was a nice FLOW of water in one direction that was visiable thru the radiator neck. I would assume that meant that the water and thermostat were working properly. That is what I was trying to test here.

Another possibility: my generator exhaust pipe and my Aqua Hot exhaust pipe both exhaust thru the roof thru the same pipe. While tailgating we noticed a black soot coming from the exhaust pipe on the roof. I changed my Aqua Hot fuel nozzle and filter after I got home thinking the soot might be coming from the old fuel nozzle. I climbed up on the roof and felt the exhaust coming out of the pipe and it was a strong flow of hot air. Do you think that the exhaust pipe could have been clogged with soot and that was causing the high operating temps?