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Intermittent overheat on Power Tech 10kw w/ Kubota engine

August 03, 2020, 06:22:09 pm

I have a Power Tech 10000 SI on our 2000 U320 that is having an intermittent overheating issue.  On our last trip, coming into camp at Palo Duro Canyon State Park, after the long decent the genset cut out.  Upon investigation once we hooked up to shore power, I found an overheat status light was showing in the genset itself.  I let the unit cool for an hour or so and fired it up without a load for an hour or so and no problems.  Fans was running fine and fluid levels were good.  Made it 5 days and no more overheating for the trip.  Yesterday, was heading out on the road again so I fired up the genny to get things cooling and it cut off with an over heat condition again after about 10 minutes.  A little frustrated, but checked fluid levels and things were good. Waited an hour or so on the trip and fired her up again and she ran fine for the rest of the trip.  Anyone have any thoughts?  I have one, but thought I would check here first to see if anyone has run into this before I start throwing parts at it.  We have about 1700hrs on the generator, about 1000 since we bought the coach last year.

Thanks in advance!
Dave

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Re: Intermittent overheat on Power Tech 10kw w/ Kubota engine

Reply #1 – August 03, 2020, 06:26:26 pm

Just had this on another coach power tech Genny, try burping the the cooling system. He had the same issues. He called Jeff at power tech and he thought that was the problem.

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Reply #2 – August 03, 2020, 08:17:14 pm

Does  your gen has an internal belt driven water pump?  Loose belt? 

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Reply #3 – August 03, 2020, 09:05:48 pm

Dave,

On your 2000 does it have 2 high point vent lines with valves that goes back to your surge tank?  Somewhere along there they changed the system.  If you have them they should be closed.  Here is a thread that hits the high points of these valves.  Generator Coolant shutoff valves If not closed it can mess with the thermostat operation.

Mike

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Reply #4 – August 03, 2020, 10:05:11 pm

A diffferent approach, it could be a wire connection on the ES-52 control board or a bad wire or connection over to the sender.  The ES-52 would be the module with all of the lights on top of the generator head.  Worth a look.

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Reply #5 – August 11, 2020, 12:09:07 am

Looks like the system had air trapped in the system.  An FOT Tech helped me purge the radiator and she took on 1/2 gallon more fluid.  Hopefully this helps.  She's purring now.  Only time will tell.  Hoping it's a simple as they didn't get all the air out when I had the system flushed.

Thanks for all the input.  I'll post if there's any new updates.

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Reply #6 – August 11, 2020, 08:54:13 am

Yeah they do that. On my trip from Texas to Vermont had to purge it several times. Each time, thought all air out, ran for 8 or more hours straight with no issues. Then overheat. Belt seems good. Next year Genny is coming out. New mounts, powder coating the base, new water pump, bearing, belts. And replacing the overheat sensor.

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Reply #7 – May 15, 2022, 12:06:39 pm

I have the same issue. Started and ran my PT10 yesterday for most of the day. Saw the antifreeze level in the bottle was low so I added more fluid. Ran ok for the rest of day. Then today ran it for about half hour and it quit. High temp light on. Reset it and it fired right up. Quit again after about 30 seconds.  Same fault light. Tried it again with same results. Same start and stop. This purging thing....is it something I can do myself?  Ir so is it reasonably achievable??
Suggestions would be appreciated

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Reply #8 – May 15, 2022, 12:24:47 pm

You need to take the radiator cap of and fill it from there. Do you have a leak somewhere.
There is a lot of hose clamps on this system so a lot of places to leak from.

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Reply #9 – May 15, 2022, 12:40:57 pm

Yes I do notice there is a little bit of leakage. Slight drips that end up in ver small pools on the ground. When it is cool how full should I fill the radiator? Till it just starts to overflow. The reason for asking is it is rally hard to tell the level where the radiator is. Seems there is a drip off the overflow bottle but I do not see that it is cracked.  The hoses on the top look ok. See pics

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Reply #10 – May 15, 2022, 01:21:16 pm

I tried pouring more antifreeze in. Started purging out the side at location of the pic

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Reply #11 – May 15, 2022, 01:28:31 pm

Pics

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Reply #12 – May 15, 2022, 01:30:37 pm

And I definitely found part of the problem the attached pics show a weld that hold the radiator still is broken. Geez these units two bit ya to death.  On to a welding shop I guess. More coach bucks to spend...

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Reply #13 – May 15, 2022, 01:51:26 pm

Look for posts on how to separate the radiator from the engine. Not too bad of a job.

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Reply #14 – May 15, 2022, 02:30:54 pm

On my 8Kw with attached radiator it rattled to pieces. Separated radiator from engine mount after rebuilding radiator along with new motor mounts. Was a big job but a good time to address multiple issues from insulation to thermostat etc.

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Reply #15 – May 15, 2022, 03:27:27 pm

A few years ago I had a failing start capacitor on the fan that caused intermittent  over heating problems on my generator.

The fan worked fine most of the time, until it didn't, then overheating.  Keep this in mind if burping the radiator doesn't work

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Reply #16 – May 15, 2022, 03:45:57 pm

That weld has been broken for a long time, it needs fixing but I don't think it's part of your
problem.

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Reply #17 – May 15, 2022, 04:24:39 pm

I had a similar issue last summer. Generator would run all day powering the refrigerator and computer, but would quit if I added an air conditioner while going down the road. MOT was supposed to check on it, and they said there was no problem, and, in fact, it powered the refrigerator and both air conditioners just fine while sitting on their lot. As soon as we started down the road, though, it would quit. When we got back to Riverton I talked to a shop, thinking that I needed to have the radiator removed, cleaned, and replaced. They said to try a purple spray cleaner (I've forgotten the name of it, but it comes from Wal-Mart) first. I pulled the generator out as far as I could, removed or loosened as much around the radiator as I could, then sprayed everything I could hit. Used a hose to rinse it off, then sprayed and rinsed twice more. Seems to have taken care of the problem.

Yes, I did make sure that I had plenty of coolant, burped it, and even replaced the radiator cap.

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Reply #18 – May 15, 2022, 05:21:19 pm

Mine was an air bubble or thermostat. Replaced the thermostat, the sensors  and the gasket.. The thermostat didnt look to good so maybe that was the issue. One time it was fine and then it wasnt.. This last round it wouldnt run past the time for self check so not sure... bled the system after and purged the air (found on the forum).    All is well now.

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