carolinahunter
I've got a Generac 15kw 43903 propane generator. Gas line is about 20' long and 1/2' pipe. It has been serviced annually by the installation company and was installed in 2006. About 2 months ago I noticed it didn't do the weekly test. I checked unit and found the overcrank LED on. I tried to crank it manually and it would crank up for about 5 seconds and shut off. It would do this 4 or 5 times and go back to overcrank. I called for service and they told me the stator was bad. It can be repaired for $2500(90 day warranty) or I can replace the generator for $6200(5 year warranty). Is overcrank a symptom of a bad stator? I just want to make sure they are not just trying to sell me a new generator.
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MikeCB
carolinahunter;37232 wrote:
I've got a Generac 15kw 43903 propane generator. Gas line is about 20' long and 1/2' pipe. It has been serviced annually by the installation company and was installed in 2006. About 2 months ago I noticed it didn't do the weekly test. I checked unit and found the overcrank LED on. I tried to crank it manually and it would crank up for about 5 seconds and shut off. It would do this 4 or 5 times and go back to overcrank. I called for service and they told me the stator was bad. It can be repaired for $2500(90 day warranty) or I can replace the generator for $6200(5 year warranty). Is overcrank a symptom of a bad stator? I just want to make sure they are not just trying to sell me a new generator.


You always want to start with fuel on overcranks. That model should be 10-12"WC for propane. That pressure has to stay in that range while static (generator not running) as well as during cranking and running. Also, what is the temperature around the time of the fault in your region. Make sure you propane set up can handle the cold temps. Propane level can also be a factor.
Again, anything preventing that pressure to be sustained. Rotor and stator shouldn't be able to cause an Overcrank.
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ED01
carolinahunter;37232 wrote:
I've got a Generac 15kw 43903 propane generator. Gas line is about 20' long and 1/2' pipe. It has been serviced annually by the installation company and was installed in 2006. About 2 months ago I noticed it didn't do the weekly test. I checked unit and found the overcrank LED on. I tried to crank it manually and it would crank up for about 5 seconds and shut off. It would do this 4 or 5 times and go back to overcrank. I called for service and they told me the stator was bad. It can be repaired for $2500(90 day warranty) or I can replace the generator for $6200(5 year warranty). Is overcrank a symptom of a bad stator? I just want to make sure they are not just trying to sell me a new generator.


I'm only commenting on the price of a new generator. What are you getting for the $6200 he wants for a new generator. If your keeping the same transfer switch the install should be quick. I think you need an extra small wire for the battery charger. Ziller has a 16KW on their site for less than $3300 and I think that is delivered.
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78buckshot
I think the "overcrank" LED and the "overspeed" LED are sometimes mis-read, from your description it may be an overspeed and should be easy to remedy. If you can remove the control compartment cover and read the LED after it faults we can help diagnose.
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MikeCB
78buckshot;37235 wrote:
I think the "overcrank" LED and the "overspeed" LED are sometimes mis-read, from your description it may be an overspeed and should be easy to remedy. If you can remove the control compartment cover and read the LED after it faults we can help diagnose.


Good point, definately needs to be verified.

an overspeed still shouldn't be a rotor and stator issue though. "flashing overspeed" maybe. But i ussually find that to just be a bad AVR.
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John R
carolinahunter;37232 wrote:
I've got a Generac 15kw 43903 propane generator. Gas line is about 20' long and 1/2' pipe. It has been serviced annually by the installation company and was installed in 2006. About 2 months ago I noticed it didn't do the weekly test. I checked unit and found the overcrank LED on. I tried to crank it manually and it would crank up for about 5 seconds and shut off. It would do this 4 or 5 times and go back to overcrank. I called for service and they told me the stator was bad. It can be repaired for $2500(90 day warranty) or I can replace the generator for $6200(5 year warranty). Is overcrank a symptom of a bad stator? I just want to make sure they are not just trying to sell me a new generator.


Find a different dealer.
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Peddler
If I am understanding this correctly the unit doesn't start. There would be no way to determine the stator is bad if the unit didn't start and a bad stator would not prevent that unit from starting. As someone else said you need a new dealer. There are countless things that may prevent the unit from starting and may be minor or more serious but a bad stator isn't one of them. You may need some parts but unless the unit has a lot of problems repairing it is the smart way to go. Good Luck, Peddler
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MEC
As the others have stated.
Get another dealer.
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BrentB
If it started and ran in manual, then shut down and tried to start again,stator shouldn't be the problem! New dealer is agreed upon!
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redman
Before I would throw another dealer under the bus and run over him, there might be a reason, this customer was told this.

If he installed it in 2006, then he might know something about this generator, we don't, and if yearly service has been done, he has a history with it, and hopefully notes, to go back to on it.

I would recommend a second opinion, before spending the money.
I suggest that to homeowners when a big price item is needed on a generator.
Thanks, Mike
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carolinahunter
Thanks for all the input. I will troubleshoot the problem and get more information and may ask for more help in repairing. Thanks again.
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Mike03
Having a 20' length of gas line with a 1/2" diameter is wrong. I could see that causing issues over the course of a few years. Why take the chance of undersizing the fuel to your genset? You need 3/4" at 20'. So if you end up replacing the unit, make sure to upgrade your gas line.
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MikeCB
Mike03;37255 wrote:
Having a 20' length of gas line with a 1/2" diameter is wrong. I could see that causing issues over the course of a few years. Why take the chance of undersizing the fuel to your genset? You need 3/4" at 20'. So if you end up replacing the unit, make sure to upgrade your gas line.


it's propane though. 20 feet of half inch BEFORE the regulator is probably ok. I see that set up all the time. No issues.
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Mike03
If that 20' run is 11-13" wc it's undersized for a 15kW. It's only rated for 160,000btu. Generator at full load calls for 260,000.
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MikeCB
Mike03;37261 wrote:
If that 20' run is 11-13" wc it's undersized for a 15kW. It's only rated for 160,000btu. Generator at full load calls for 260,000.


Correct, but again it depends on the setup. Prop companies around here will run 1/2 or smaller to the generator at a much higher pressure. I can't quote the exact pressure but I've accidentally connected my gauges to that side and the gauge broke instantly. Then at the generator a regulator is installed to step it down to 11-13 usually about 18 inches before it actually enters the generator.

There are more factors than "pipe size @ pipe length" that we currently don't know.

Pressure and volume can be tweaked relative to each other for the same final BTU output. Similar to being able to get roughly 3600 watts through a 14 gauge wire at 240 volts. If you drop that voltage down to 120, you now need 10 gauge wire to accomplish the same 3600 watts.
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Mike03
MikeCB;37265 wrote:
Correct, but again it depends on the setup. Prop companies around here will run 1/2 or smaller to the generator at a much higher pressure. I can't quote the exact pressure but I've accidentally connected my gauges to that side and the gauge broke instantly. Then at the generator a regulator is installed to step it down to 11-13 usually about 18 inches before it actually enters the generator.

There are more factors than "pipe size @ pipe length" that we currently don't know.

Pressure and volume can be tweaked relative to each other for the same final BTU output. Similar to being able to get roughly 3600 watts through a 14 gauge wire at 240 volts. If you drop that voltage down to 120, you now need 10 gauge wire to accomplish the same 3600 watts.


I've installed gas lines to 100+ gensets and figured ide add some useful info to the op of the thread. I wrote if supplying the gen for 20' with 1/2" pipe at 11-13"wc, it would be wrong. I didn't see anything stating it was a 2stg setup. Installing the second stage regulator 18" away from the generator inlet is also incorrect.
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