Powertech Generator/Kubota overheating

[Peter Amos]

After an intermittent amount of time (3 hours to 2 days) the generator in my Wanderlodge will shut off showing overheating. The push button is blinking three times meaning an overheat. Anyone have the issue and how did you resolve. I have checked the basics - water level, air flow on radiator, etc. Any help would be appreciated.

[Arcticdude]

Peter,

I'd say it's only a few choices here. The thermostat may not be fully opening, which would allow for a slow overheat. Depending on how hard you're working it, would determine how fast it overheats. Second, the squirrel fan could be stopping due to it getting hot. You'd have to watch it to see what's going on.

Where did you check the water level?

[cmillsap]

In addition to what John said above, the voltage regulator could be another reason. The radiator fan runs off the power from the generator. If voltage is lost intermittenly due to the voltage regulator overheating or going bad, the radiator fan will stop and the Kubota will overheat.

Do you know if the gen stopped producing power a few minutes prior to it shuting down? If it did then the problem is probably electrical.
If the bus had power from the generator up until the gen shut down checking the items John listed above should be done. Also a check of the wiring running to the fan motor for a loose connection would be wise. Be careful as that is 220VAC to the fan motor.

[mikebulriss]

(08-12-2014 15:10)Peter Amos Wrote:  After an intermittent amount of time (3 hours to 2 days) the generator in my Wanderlodge will shut off showing overheating. The push button is blinking three times meaning an overheat. Anyone have the issue and how did you resolve. I have checked the basics - water level, air flow on radiator, etc. Any help would be appreciated.

Peter,

When was the coolant replaced? I had a similar problem crop up out of the blue with the Powertech Kubota combo on my 91 after I had it for a short while. When it happened, flushing the rad cooling system had already been on my 'to do' list since the coolant looked somewhat dark. I discovered that a prior owner had already removed the thermostat, so that eliminated that as the cause of the overheating. I added two cans of Prestone heavy duty radiator flush and let it run the recommended amount of time and then opened the radiator petcock and drained the system. From the looks of the output, it definitely had scale build up and needed the flushing. I refilled with tap water and ran it some more, then opened the radiator petcock again, left the water hose running in the expansion tank filler and let it run some more until every thing coming out the radiator petcock was totally clear. After it cooled, I opened the block drain as well and drained the block water jacket. I refilled with a 50-50 mixture of distilled water and Fleet Charge SCA Precharged Antifreeze & Coolant, from the Tractor Supply Company. No more overheating problems and it runs at 160 degrees under all conditions now. I did not replace a thermostat since it is working fine without one.

FWIW, YMMV, etc. Good luck.

[timetravelers]

I had overheating problems, finally fixed it by taking grill out under floor under radiator, cleaning radiator thoroughly from underneath. Now has run for 12-18 months at 160 degrees.

[John H]

Our Powertech/Kubota overheated at Quartzsite in 2010 seven months after we bought our coach. I found the squirrel cage fan nearly seized up. Squirted WD-40 into the oil ports until it freed up. Now use Zoom Spout Cooler motor oil regularly. While we're talking generators, our exhaust pipe fell down while traveling I-90 in Montana this summer. The weight of the pipe broke the three saddle straps tack welded to the heat deflector. The exhaust had evidently been fitted up to the built in stack, but the clamp not properly tightened. The clamp is in the black box at the bottom of the stack. Something to check.

[GregOConnor]

Could be air in the coolant getting to the waterpump and causing the pump to just spin and rotate the air. in that instance look for the bleed or loosen a hose. the best way to determine if it is not pushing water is to check the temp at the radiator. when the engine is at temp ,t stat open,water should be pumping thru the radiator so temp should be high all thru the system. If it is in the 91-99 era bus there is also a squirrel cage fan on the back of the gen head under the bus that cools the gen head and genset compartment. the back fan doesn't spin fast, it just moves air. if you jack it up to see, remember to block up an escape. there could also be a need to rod the radiator. removal is easy and established radiator shops rod for less than 100. with a quick turn around. I replaced my squirrel cage with hayden dc setup because the blades were off balance. I can ship you the old motor for freight but would suggest the 12volt hayden mod if the fan is the issue.

[ernie ekberg]

Greg- good to hear from you

[bobloomas]

(08-19-2014 21:12)ernie ekberg Wrote:  Greg- good to hear from you

Times 2

[RetDA]

Never had mine "overheat", but last spring my generator seemed to be "lugging" (for lack of a better term). Seems my fan motor was about to go south. I bought a new motor and to install it, the techs had to remove the squirrel cage and fan.

When the squirrel case and fan was removed, the radiator underneath the squirrel cage was full of dirt, leaves, sticks, dead bugs, butterflies, etc. I cleaned it thoroughly, but the thought I had is there's got to be a better way to clean that bugger, lying flat on the floor of the genny compartment.

All that accumulated stuff has got to be bad for proper operation.