# Honda en3000is inverter generator turns over hard



## blacktrain (Apr 1, 2015)

I have a Honda eu30001s inverter generator. (GCAE-1276265) The engine runs good and the generator produces power like it should. The problem I am having is, as the rotor rotates around the stator there is a lot of resistance, so much resistance that the electric starter does not have enough power to turn the engine over. Also you can't start the engine with the rewind rope either because there is so much resistance, you can't pull it fast enough to start the engine. The electric starter is new, I pulled the cam shaft out to make sure the compression release was functioning correctly, everything is in good shape. With the engine tore down, if you remove the rotor from the stator the engine turns over very easy, put the rotor back over the stator and rotate the rotor by hand and there is so much resistance you can hardly rotate the rotor. I would appreciate anyone's help. Thanks...


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## ToolLover (Jan 13, 2020)

blacktrain, I have seen this happen when the armature is bent. 
I experienced this with starters.
As you stated you have already had it removed, so put it into a lathe and see if it is warped.
Don't ask me how it happens, but old starters often had this problem.


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## blacktrain (Apr 1, 2015)

I appreciate the quick response, the armature is not bent, it is almost like it is reverse polarity. Remember, this is an inverter generator. You don't have a rotor that slides inside the armature, you have a rotor that looks like a flywheel that goes over the outside of the stator. If you rotate the rotor (flywheel) that sets over the stator by hand it seems that the magnetic field is so great that it turns hard. Before I fork out $400.00 for a rotor and stator I need to make sure this is what the problem is. I sincerely appreciate all the help...


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## drmerdp (Apr 10, 2018)

I’ve heard of this before but on a EU6500is. Try unplugging the inverter unit and attempt to pull start the motor.


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## blacktrain (Apr 1, 2015)

I have tried un-plugging the inverter unit but still get the same results. I appreciate your thoughts, I am sure with everyone's help we will get to the bottom of this yet. Thank you so much for your help...


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## drmerdp (Apr 10, 2018)

Ok, how many hours would you guess is on the unit? 

If the valve lash is out of wack, (too much lash) then the decompression mechanism won’t function. This would increase starting efforts.


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## RedOctobyr (Aug 8, 2018)

He said it only happens when the rotor and stator are installed together, though. Making me think it's not something like valve lash messing with the compression release.


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## iowagold (Jan 22, 2020)

sounds like a short in the stator or a clearance issue with the rotor to the stator or engine block bearing...
paint pen on the rotor and see if it is rubbing...
maybe distorted stator (coils for the inverter are stationary)
rotor has magnets...
I have seen clearance issues on the plastic formed stator from over heat as well as coil flash over issues from coil overload hot spots...
ohm meter on the 6 wires for the stator and also check to make sure they are open or no connection to ground with the ohm meter.

they all pull over hard...
but then I have a bad right shoulder right now.
make sure the battery is a fresh new one and full charge.
note: they are not full charged when you buy them from the parts store.

new hd start cables hot and ground are nice!!
I have swapped out the oem ones on the 7000is units for 4 gauge welding cable for the units in the fleet.
sure helped on the spin!!
also I use the battery maintainer charger on them solor brand from napa.
poust usa
link for that is on the poust home page.
they sure help keep the battery's in good shape for units that are not used every day!
I also have those on every car truck or heavy equipment in the fleet!
nice for cold winter starts!!
these work better than battery tender brand for me.


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## blacktrain (Apr 1, 2015)

Just a quick message to everyone, I want to say thank you for all your much needed help and I want everyone to know how much everyone is appreciated. I am going to do more tests and I will respond soon with the results. I know with everyone's help we will figure this out, again a huge thank you to everyone...


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## RedOctobyr (Aug 8, 2018)

I am not an EE, but as iowagold said, I would want to check the resistance of coils, both "along" the coil (one end to the other), as well as to ground. 

I don't know if something like a short to ground would make it harder to turn, but it seems possible.

If it helped for testing, you could also remove the spark plug, to make the engine easier to turn.


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## drmerdp (Apr 10, 2018)

RedOctobyr said:


> He said it only happens when the rotor and stator are installed together, though. Making me think it's not something like valve lash messing with the compression release.


Whoops, missed that. Had to reread his first post.

So if it’s only hard to turn over with the stator and rotor assembled it can only be 2 things. The rotor physically rubbing the stator, or an electrical anomaly causing the stator to magnetically drag on the rotor. 

Found where I saw the Hard start EU6500is. Good old Taryl Dactile. 

https://youtu.be/tBJkV8uF4-s


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## iowagold (Jan 22, 2020)

drmerdp said:


> Whoops, missed that. Had to reread his first post.
> 
> So if it’s only hard to turn over with the stator and rotor assembled it can only be 2 things. The rotor physically rubbing the stator, or an electrical anomaly causing the stator to magnetically drag on the rotor.
> 
> ...


yea but we have already been there with disconnecting the coil load!
that is basic inverter gen 101 stuff.
if the inverter caps are shorted it will load the coil to zero ohm load...
the magnetic field is locked at that point. 
has to be a drag on the rotor to stator or bearing or block.

just a darn shame honda has to pot all of the modules to keep the inverter spies at bay...
other wise we could repair at a component level the inverters!

oh yea if you have a bad honda inverter.
pm me!!
I buy the bad ones!!


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## iowagold (Jan 22, 2020)

did you unplug all of the wires on the inverter unit??
also with the spark plug removed
if not try that to see if it pulls over easy.

it should role over easy!


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## RedOctobyr (Aug 8, 2018)

blacktrain said:


> I have tried un-plugging the inverter unit but still get the same results. I appreciate your thoughts, I am sure with everyone's help we will get to the bottom of this yet. Thank you so much for your help...


Assuming that this un-plugging provides a complete disconnection of the inverter from the rotor/stator, it sounds like an inverter interaction has kind of been ruled out.


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## blacktrain (Apr 1, 2015)

Yes, all wires have been unplugged from the inverter unit, and the spark plug has been removed, and still turns hard, again, nothing is rubbing or scraping, once the rotor has been placed over the stator it turns over with a lot of resistance.


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## iowagold (Jan 22, 2020)

did you un plug the spark module too?
if so then

next would to be remove the stator...
then put the rotor in place to see if it free wheels then.

a shorted stator will almost lock up the rotor..


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## iowagold (Jan 22, 2020)

oh yea a thought did you disconnect all the wires to the stator??
the full wave bridge for the dc!!
the dc diode pack could be shorted...
maybe 25% more load if it is shorted..

unplug all the wires to the stator then try the role over.:tango_face_devil:


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## blacktrain (Apr 1, 2015)

I have disconnected the spark plug module and got the same result. I did as you suggested and removed the stator and put the rotor back on and with the stator removed it turned over very easy. Yes i disconnected all the wires from the stator and with all wires removed it still turns hard. I was just wondering, if everything is working correctly, is there suppose to be any resistance at all when turning the rotor? As always, I appreciate everyone's help, I would not be able to get through this without you guys...


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## iowagold (Jan 22, 2020)

one of two things is happening
rotor is physically hitting the stator or the stator has shorted coils. 

will all the wires disconnected from the stator.
the rotor will free wheel as there is no path for resistance in the stator coils.

if you short the coils then the current generated has no path to release the energy.
so it loads the stator coil as coupled to the rotor. (hard to turn over)

the same thing happens when the inverter shorts out inside..
hard to turn over.

you did the paint pen trick on the rotor to see if it was rubbing off on the stator right??

if so the rotor has to be bad. check it close again with a good fluke meter.
page 78 of the owners manual has the diagram for the stator coils
the down load for that manual is up on the honda forum
in the files section.

did the stator have any discolored windings?


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## blacktrain (Apr 1, 2015)

The rotor is definitely not hitting or rubbing on the stator. I guess i am leaning toward a bad stator because with all the wires disconnected from the stator like you have suggested, the rotor will free wheel but if there are shorted coils then like you also suggested, the current generated has no path to release the energy. Makes complete sense. Thinking about spending the money for a new rotor and stator, what are your thoughts, or am i jumping the gun? I really want to be sure because i hate the thought of buying a new rotor and stator and not solve the problem. As always, i appreciate the guidance and your expertise through all this.


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## Melson (Dec 8, 2019)

blacktrain said:


> _is there suppose to be any resistance at all when turning the rotor?_


I would expect to feel a slight resistance in both directions from magnetic flux.


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## RedOctobyr (Aug 8, 2018)

Have you checked the stator resistances with a multimeter yet? I would imagine you'd need to check through each coil(s), as well as from each coil to ground.

Ideally there are specs that you can check against. But barring that, if a coil has a short to ground, for instance, you can probably conclude that it has failed.

Forgive me if I'm missing something, and I haven't worked on these. But I'd expect that a meter will answer the question fairly conclusively.


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## ToolLover (Jan 13, 2020)

There are two things that can cause resistance when turning.
First is the magnetic resistance as Melson explained.
It can be determined by a slight hold back and increase to full strength.
Then it will release or in some case the rotor will jump back.
Similar to trying to put two magnets together.
The other is drag on a rotor is as it comes into contact with the field.
This type usually holds the rotor steadily and does not release its hold.
You mentioned that you had disconnected all of the wiring to the fields.
That leads me to thinking that there is no magnetic hold on the rotor.
One other thing lacking is the exciter coil and what part it could play in this resistance.
The exciter coil is activated by two magnets on the flywheel.
As for any drag, I doubt the exciter magnets are of any consequence.


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## blacktrain (Apr 1, 2015)

The rotor on this generator has 17 magnets. If i can figure out how to, i will post some pics.


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## Osviur (Sep 7, 2015)

Hi Blacktrain,
IF you can start the genset, it is possible to check the AC voltage produced by the stator windings. The main winding is a 3 phase, star connected, giving a variable voltage and frequency, depending on the engine RPMs.
Unplug the connector with the 3 red wires and check the output voltage in the 3 possible combinations: AB, AC, BC, running the engine at low RPM. Be very careful doing this, due to the high voltages present.
All the readings must be the same, one low reading is a short in the corresponding coils. It means stator replacement.
Hope this help


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## iowagold (Jan 22, 2020)

blacktrain said:


> The rotor on this generator has 17 magnets. If i can figure out how to, i will post some pics.


if it is only 17 magnets something is wrong..
it should be 18 magnets on the inside









or click the pix here
http://www.poustusa.com/GENERATOR_HELP_PAGES/HONDA_EU3000I_PIX/eu3000isrotormagnetpix.jpg


:tango_face_devil:

the devil is in the details!!:tango_face_grin:


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## iowagold (Jan 22, 2020)

stator coils on the eu3000i should look like this
click the below links for the stator pix
coil 1
http://www.poustusa.com/GENERATOR_HELP_PAGES/HONDA_EU3000I_PIX/eu3000isstator1pix.jpg

coil 2
http://www.poustusa.com/GENERATOR_HELP_PAGES/HONDA_EU3000I_PIX/eu3000isstatorbacksidepix.jpg

3 plugs 
www.poustusa.com/GENERATOR_HELP_PAGES/HONDA_EU3000I_PIX/eu3000isstatorplugspix.jpg

make sure all 4 plugs are disconnected when testing for the rotor turn

the 3 red wires are the 3 phase main winding 1.4 - 1.5 ohms
the two grays are the sub winding 0.1 to 0.2 ohms
the 2 brown#7 are the dc winding 0.1 to 0.2 ohms
and the 2 brown or red#8 are the onboard battery charge winding 0.1 to 0.2 ohms

all of the 4 sets windings should not conduct to each other
watch for hot spots and or corrosion.

more pix and data are on the honda forum
https://hondagenerator.groups.io/


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## blacktrain (Apr 1, 2015)

It does have 18 magnets I must have hit the 7 instead of the 8. My fault. sub winding I get 0.2 ohms, dc winding 0.2 ohms, charge winding 0.2 ohms, 3 phase main winding 0.7 ohms.


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## iowagold (Jan 22, 2020)

or you could buy a matching rotor and stator new
stator 31120-ZS9-C31
https://www.partsfish.com/oemparts/p/honda_power_equipment/31120-zs9-c31/stator-assy

rotor 31130-Z03-C02
https://www.partsfish.com/oemparts/p/honda_power_equipment/31130-z03-c02/rotor

then it would be new. and matching.
the numbers look off on the stator 3 phase.


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## RedOctobyr (Aug 8, 2018)

blacktrain said:


> It does have 18 magnets I must have hit the 7 instead of the 8. My fault. sub winding I get 0.2 ohms, dc winding 0.2 ohms, charge winding 0.2 ohms, 3 phase main winding 0.7 ohms.


What are the resistances to ground? As iowagold said, the 3 phase is low. If it also has continuity to ground, that could help confirm that something is wrong with it. It could presumably have a failure between the windings, without shorting to ground, but it's something to check. I'd also check between the coils, from to another.


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## iowagold (Jan 22, 2020)

if you were closer blacktrain I would say bring it over!!
I do maybe 7-8 gens a week...
always learning!!
there is always a new twist on the equipment!!
LOL!
always use a good fluke meter to check these honda gens..

and a scope meter or an classic scope is nice to look at the wave form if you are having inverter issues...
you can see if a section of the inverter is not working right.

yea guys hand on to your old parts and old carbs..
ship them to me.
I use the carbs as jigs for making housings / throttle body's from scratch...
for fuel injection.

I have on my list a 3d metal printer.

right now I use a polymer printer for prototype..
then we flow bench the parts then back in to cad with the tweaks..
then to a mill with t6 aluminum billet...
and make out own valve body's.. 
big bucks!! takes about 5 k in time to do one...
at least the first time..
then it is about 500 bucks after the numbers are in cad to make one.


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## blacktrain (Apr 1, 2015)

I have ordered a new stator and rotor and when i receive them and install them i will post the results. I appreciate everyone's help, you all have been great. Thanks...


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## drmerdp (Apr 10, 2018)

Alrighty, let’s see what happens.


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## blacktrain (Apr 1, 2015)

I received the new rotor and stator, put it all back together, held my breath, and started it up, ran like a new generator and performed perfectly. I certainly learned a lot from all this and i could not have done it without everyone's help. I want to thank each and everyone of you for all your patience and help it has been greatly appreciated. Thank you, Thank you, Thank you.................


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## Melson (Dec 8, 2019)

That was a unusual problem. For example, over 42 years of telecom power work I had but two failures directly attributable to rotors.

Glad to hear you got it working. 
Question: Did stare-&-compare to see if you could discover the issue?


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## drmerdp (Apr 10, 2018)

blacktrain said:


> I received the new rotor and stator, put it all back together, held my breath, and started it up, ran like a new generator and performed perfectly. I certainly learned a lot from all this and i could not have done it without everyone's help. I want to thank each and everyone of you for all your patience and help it has been greatly appreciated. Thank you, Thank you, Thank you.................


That’s awesome, gotta add this fix to my memory bank.


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