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Foretravel Motorhome Forums => Foretravel Discussions => Topic started by: AC7880 on August 26, 2017, 11:07:39 pm

Title: Generator overtemp shut down
Post by: AC7880 on August 26, 2017, 11:07:39 pm
10KW Power Tech w Kubota.  Today the generator is shutting down after 2-3 minutes with overtemp light on. 

Coolant tank full, overflow bottle full, oil level normal no contamination.  New coolant at OTM in Nac in March, ran about 8 hours since then.  Total hours around 868.  Both glass fuses look good, I reset the breakers, squirrel cage blower on radiator running fine, see no slippage on belt to water pump.  Checked connections on wires to senders - looked ok.  Near full tank of fuel.

My guess is stuck thermostat or failed temp sender.  Have not researched yet.  Will do search here and look in my coach documents.

 Bad day to happen, running south on I5 in Oregon with heavy traffic and HOT - no roof airs. Is the temp sensor the one at top? Where is the thermostat and how much coolant will I lose to pull it? Part numbers for sender and thermostat?  (I may find the answers when I search and check my coach documents tomorrow).

Stationary for at least one month at Escapees park in Sutherlin Oregon, so time to figure it out and hopefully fix it myself.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 12:29:28 am
Found this so far: thermostat 19203-73010 and thermostat 19434-73010 .

Thermostat gasket 15676-73270

I'll have to look tomorrow at the tags on the generator for the specific model number. 
Parts: Senders (https://www.powertechgenerators.com/collections/senders) 

And: All Parts (https://www.powertechgenerators.com/collections/all-parts) 

Title: Re: Generator overtemp shut down
Post by: Mark D on August 27, 2017, 12:32:15 am
If you find a harbor freight you can buy their infrared temp gun and shoot it at the coolant outlet on the generator.  If it's a stuck thermostat the temp right at that outlet should be high.
Title: Re: Generator overtemp shut down
Post by: ltg on August 27, 2017, 12:43:14 am
After a coolant change, if the generator is not properly burped, it will shut down as you are experiencing. However, for it to start after 8 hours of service would be unusual.  All it will take to check that out is a little time. Foretravel has provided an instruction sheet that explains the procedure. The procedure is posted on Beamalarm.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 01:02:54 am
If you find a harbor freight you can buy their infrared temp gun and shoot it at the coolant outlet on the generator.  If it's a stuck thermostat the temp right at that outlet should be high.


I have a infrared gun. I'll try that. Shut down comes very quickly, so I'm thinking over temp sensor versus thermostat. I wonder if NAPA has parts, or I need special order from the links I posted above?
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 01:03:33 am
After a coolant change, if the generator is not properly burped, it will shut down as you are experiencing. However, for it to start after 8 hours of service would be unusual.  All it will take to check that out is a little time. Foretravel has provided an instruction sheet that explains the procedure. The procedure is posted on Beamalarm.

I'll look for the burp procedure. Can't hurt to try that.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 01:16:00 am
Have a plan for tomorrow. Measure temp, remove wire from temp sensor, remove temp sensor to remove air pocket if present.

Generator Engine Troubleshooting (http://www.beamalarm.com/Documents/Generator/generator-engine-troubleshooting.html) 

Flush and Fill Generator Cooling System (http://www.beamalarm.com/Documents/Generator/flush-and-fill-generator-cooling-system.html)

Procedure for bleeding the coolant system on Powertech Generators (http://www.beamalarm.com/Documents/Generator/procedure-for-bleeding-the-coolant-system-on-powertech-generators.html) 
Title: Re: Generator overtemp shut down
Post by: rbark on August 27, 2017, 01:20:35 am
The two ball valves going into and out of the expansion tank must be in the closed position. Handles must be in the up/vertical position.
Title: Re: Generator overtemp shut down
Post by: sedelange on August 27, 2017, 01:21:59 am
On my 2005, when generator shuts down due to clogged fuel filter I get an Overtemp light.  If your generator isn't hot, change fuel filters and try again.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 01:31:45 am
The two ball valves going into and out of the expansion tank must be in the closed position. Handles must be in the up/vertical position.


That's the current position on the ball valves  with the over temp light coming on and gen shutting down.

Thanks to all for the info and suggestions. 
Title: Re: Generator overtemp shut down
Post by: Old phart phred on August 27, 2017, 01:57:24 am
The two ball valves going into and out of the expansion tank must be in the closed position. Handles must be in the up/vertical position.
Huh, so what is the expansion tank for if both valves are in closed position? Lost in translation somewhere.
Title: Re: Generator overtemp shut down
Post by: Mark D on August 27, 2017, 12:07:58 pm

I have a infrared gun. I'll try that. Shut down comes very quickly, so I'm thinking over temp sensor versus thermostat. I wonder if NAPA has parts, or I need special order from the links I posted above?

You're probably right.  Thermostats have a tendency to fail open.  I believe mine is probably on the way out as it takes the generator like 20 minutes to warm up.
Title: Re: Generator overtemp shut down
Post by: wantabe on August 27, 2017, 12:54:51 pm
First check to be sure that infant the engine is over heating or maybe a bad sensor.  if it is too hot, check the radiator cap seal and pressure and the concentration of the coolant. If the coolant is too concentrated, it won't cool well. If the water pump is putting too much water through the radiator too quickly the coolant won't have time to cool. and be sure the water pump is rotating in the proper direction for the impellers to pump.


wantabe
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 02:36:22 pm
Two comments before I dig deeper into the gen over-temp issue.

1.  The overflow plastic bottle is much fuller than before.  Since I have added no additional coolant this would "seem" to mean air trapped somewhere in the system, though I can't see how that would have happened.

2.  The temp sensor does not want to come out.  I'm afraid I may break it off if I put more pressure on it.  The sealant used when installed must have set up VERY hard.

Title: Re: Generator overtemp shut down
Post by: rbark on August 27, 2017, 03:46:10 pm
Old phart phred
  Those valves/hoses are for bleeding air out of the system after changing fluids. That's what my instruction say anyway.
 Maybe yours is different.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 03:52:13 pm
Old phart phred
  Those valves/hoses are for bleeding air out of the system after changing fluids. That's what my instruction say anyway.
 Maybe yours is different.

Yep, and here is the link: Procedure for bleeding the coolant system on Powertech Generators (http://www.beamalarm.com/Documents/Generator/procedure-for-bleeding-the-coolant-system-on-powertech-generators.html)

Those hoses to be removed were stuck on so hard I had to cut them off.  Haven't pushed air thru yet.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 05:32:43 pm
After a coolant change, if the generator is not properly burped, it will shut down as you are experiencing. However, for it to start after 8 hours of service would be unusual.  All it will take to check that out is a little time. Foretravel has provided an instruction sheet that explains the procedure. The procedure is posted on Beamalarm.


It was apparently a small  air pocket at the very top of the generator where the temp sensor is.  Ran the beam alarm procedure, and ran generator one hour afterwards with a load and with 97 degrees ambient temp.

It was a fairly small burp with air out of the two hoses (or one of the two).  Burped it twice using 1/2 gallon of fresh 50/50 coolant to replace what came out while burping the coolant into a container..

On a side issue, the overflow tank is not recovering into the surge tank.  No pressure at radiator cap after one hour run.  Cap looks fine and is fairly recent (replaced by PO).  I suspect the soldering at the filler neck of the surge tank, though I see no coolant loss at filler neck (suspect just vapor release).

I'll post some pics later.  Thanks to all for help and suggestions.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 07:09:50 pm
The two hoses from the aeration valves on the surge tank come in just behind the back of the temp sensor area - one upper and one lower.

Looking in from the front, the temp sensor is upper right side.  Belt driven water pump at right side.

Last pic is the solder that I think has pinholes letting pressure out.  I wonder if JB weld is capable of retaining the 13 psi and heat??



Title: Re: Generator overtemp shut down
Post by: Pierce & Gaylie Stewart on August 27, 2017, 07:24:33 pm
I've used JB Weld several times on a radiator. One time, I hit a bump in my old van and the fan sliced into the radiator. I crimped off the broken tubes and filled the ends with JB Weld. Worked fine.

It's pretty easy to use a HF small torch or even a plumbing torch to solder brass/copper. Use flux and plumbing solder. I used this method to repair the overflow tube at the radiator cap on our U300. Everything has to be very clean or the solder won't flow correctly. It's not like the old days with lead in the solder. Probably good it's not the old days.

What is the white stuff?

Pierce
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 07:27:36 pm
I've used JB Weld several times on a radiator. One time, I hit a bump in my old van and the fan sliced into the radiator. I crimped off the broken tubes and filled the ends with JB Weld. Worked fine.

It's pretty easy to use a HF small torch or even a plumbing torch to solder brass/copper. Use flux and plumbing solder. I used this method to repair the overflow tube at the radiator cap on our U300. Everything has to be very clean or the solder won't flow correctly. It's not like the old days with lead in the solder. Probably good it's not the old days.

What is the white stuff?

Pierce


The white stuff is actually silver in good light, and a previous solder repair.
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 07:31:19 pm
I haven't soldered anything since I was 17 years old in a high school electronics class. 

I'm thinking of wire (small fine brass)  brushing it well, using electronic cleaner next, one final wire brushing, then a coat of JB water weld. Specs show that it "should" work.  Much easier for a home repair, but if it doesn't work harder to clean well enough for future pro repair.

WaterWeld Epoxy Putty | J-B Weld (https://www.jbweld.com/products/waterweld-epoxy-putty) 
Title: Re: Generator overtemp shut down
Post by: Michelle on August 27, 2017, 07:32:55 pm

The white stuff is actually silver in good light, and a previous solder repair.

That was done by FOT in October 2012 (when we replaced the rad cap).  They basically used what I call a "creme brulee torch" as I have the same model at home and that's what I use it for....
Title: Re: Generator overtemp shut down
Post by: AC7880 on August 27, 2017, 07:39:12 pm
What do you think about using JB weld?  Not sure I want to buy solder and a torch, since I have no experience soldering in the last 40 plus years.

So many types these days.

Epoxy & Adhesives | J-B Weld (https://www.jbweld.com/collections/epoxy-adhesives)

Specialty Products | J-B Weld (https://www.jbweld.com/collections/specialty-products)
Title: Re: Generator overtemp shut down
Post by: Michelle on August 27, 2017, 08:09:19 pm
What do you think about using JB weld?  Not sure I want to buy solder and a torch, since I have no experience soldering in the last 40 plus years.

Dan,

If that question was directed to me/Steve, I defer to the forum expertise.  That said, the Big Green Egg (BBQ) community I'm part of uses JB Weld to repair their BGEs, and those get up to temperatures much higher than a radiator. 
Title: Re: Generator overtemp shut down
Post by: AC7880 on September 17, 2017, 11:27:18 pm
I never followed up on this.  I did use JB Weld over the existing solder in a fairly thick and wide coat (after thorough wire brushing then cleaning), let it dry 48 hours since we had no need to use it.  Seems to have worked.

So, burping the gen using procedures above in the thread, then sealing gen surge tank filler neck with the slow drying version of standard JB Weld has resolved the issues.