Kohler 6.5ESZ Control Board Relays

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arob

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I have a Kohler 6.5ESZ generator that will crank and fire, but shuts right off after letting go of the start switch. You can eventually get it to stay running if you tap on the relays on the control board. the control board is almost $200, and i have a hard time replacing the board because of a $5 relay. the relays look like they got hot, and the writing on the front is all bubbled off, so i cant get part numbers off of them. does anybody know what brand and part/model number of the clear relays in the picture? I can solder new relays onto the board, but not sure what they are. I'm assuming its just a spdt relay with the solder pins, but not sure. im thinking something like an Omron PCB power relay G2R-1. anybody have any insight?
 

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alldodge

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Describe how you get it started a bit more. I have one that has issues starting but its not the relays.
 

arob

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using either the start button on the power distribution panel in the cuddy or locally on the gen set itself, it does the same thing. if you hold the start, it fires and starts to come up to speed, but as soon as you let go of the start button, it shuts down. it stays cool once you get it to stay running, so its not getting hot. its oil level is ok, so im assuming its not because of oil level/pressure. once you get it running, ive run it for hours with no issue, but it always does the same thing if you shut if off and attempt to restart.

i tapped on the relays with the butt of a screwdriver as i let go of the start button and about 1 out of 3 times it'll stay running.
 

alldodge

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My kohler does the similar starting issues.

My gen: try to crank and it does a lot of it. It use to have a fuel shut off solenoid which was bypassed and replaced with an anti siphon valve at the tank.

If I held the start button it would keep running. To help it start and hold sooner I would do it at the gen. As it started cranking the choke solenoid would cycle on/off. I would hold the choke close while starting and it would start and hold with less times. This tells me its not getting enough fuel.

So I installed a by pass switch to turn the fuel pump on before I tried to start it. This was a momentary ON switch like the start switch. I would hold the fuel pump switch ON for a good minute or more before I tried to start it. By doing this it was able to start and run with only a couple to three tries.

The issue I was looking at was the fuel line feeding the gen was 3/8 ID and the little fuel pump on the gen only needed 1/8 to no more then 1/4 ID fuel line. It takes quite a bit to fill the large hose up with fuel, then to be an issue the fuel bowl also needs to be filled.

The kohler gen fuel pump only runs when the motor is running :facepalm: which leads me to who ever thought of that one :noidea:
The fuel pump will run while starting but only after it has been cranked long enough to signal the oil pressure switch to close

Just what has gone on with mine, not sure if yours is the same
 

arob

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hmm...i'll have to do some troubleshooting on mine to see if i can find a similar situation as yours. i did notice that my choke turns on while cranking, but as soon as it fires off, it opens back up. is that what its supposed to do (it would make sense as that's what you do when you manually choke any other engine)?

i don't think i want to install a bypass switch for the fuel pump, at least down near the generator. i want to be able to start the gen from my pdp in the cuddy. as you probably know (since you're a formula owner too), its kind of a pain to get down in the bilge on these older formulas. my 34pc, i have to fold up all my seats in order for the hatch to be able to open. i run my generator for short periods a couple times a day, so i don't want to have to disrupt my guests to start the gen.

my only difference from yours, is i can get it to stay running on a dry start after its been sitting all week by doing my relay tap method.

do you remember what your led's did on your control board? i believe the top left led lit during cranking on mine, and once it lit off, the top right led would light up. if it stalled out, the top right led would go out.
 
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alldodge

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Mine is a 94 model and don't have led's. My choke would flip on and off has it was cranking. This is the reason I tried to keep it on.

The prime switch could also be added to the interior panel, but since I rarely use my gen (only about 120 hours) it doesn't get started but maybe 3 times a season and that's only if I remember.

Yours has probably a newer design then mine and may not have the same issue
 

HT32BSX115

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Howdy, Welcome aboard!

This thread should really be in the Electrical, Electronics, Audio and Trolling Motors section. Maybe a Mod will move it for you!!


I had a similar problem with a "control board" for a gas furnace. The relay that powered the hot surface ignitor had burned contacts.

I scrounged around in my "junk box" and found a relay that was on a microwave oven controller that I had caniballized many years ago and it was the same coil voltage with the same number of contacts and size.. It was a simple process to desolder the old one and install the replacement.

2213728-40.jpg


If you cannot get the part number of the relay, you might have to measure the coil actuation voltage and count contacts to determine what will replace it.

If you can't find the exact replacement, you could wire in a suitable relay and hot glue it to the chassis etc.


It's doable, but it's probably not worth paying someone to do it. In that event, it's probably better to just buy the replacement board.


Regards,


Rick
 

alldodge

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If you go after market relay I would recommend making sure the relay is sealed
 

mjf55

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arob, Can you read any of the information off of either relay? Looks to me some of the information on the bottom relay ( in your picture ) is somewhat legible.

I found that for your kohler 6.5esz generator, the controller board is part number c-229388. I found a site ( old site, ) but it has the best picture of the board that I found so far. I can read some, but not all of the information on the relay. Perhaps with what you can read ( take a close up picture of the top surface of the relays ) and this photo, we can figure out what part it is.
Photo on this page -> http://www.generatorpanels.com/229388.asp

Also, searching found a few sites that will repair this board for about 100 dollars.
 

HT32BSX115

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Pretty hard to read the model numbers of those relays. You might be able to get them to tell you the relay part numbers or sell you relays.
All said, $89 is a pretty good deal to "repair" your board..

Most relays are either 6, 12 or 24v coils. Those are probably 12v. All you would need to do is match the contacts etc...

Found that Omron relay on eBay for $7.95

And it looks like the other relays with the clear covers are also 12v
 
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arob

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Howdy, Welcome aboard!

This thread should really be in the Electrical, Electronics, Audio and Trolling Motors section. Maybe a Mod will move it for you!!


I had a similar problem with a "control board" for a gas furnace. The relay that powered the hot surface ignitor had burned contacts.

I scrounged around in my "junk box" and found a relay that was on a microwave oven controller that I had caniballized many years ago and it was the same coil voltage with the same number of contacts and size.. It was a simple process to desolder the old one and install the replacement.


If you cannot get the part number of the relay, you might have to measure the coil actuation voltage and count contacts to determine what will replace it.

If you can't find the exact replacement, you could wire in a suitable relay and hot glue it to the chassis etc.


It's doable, but it's probably not worth paying someone to do it. In that event, it's probably better to just buy the replacement board.


Regards,


Rick

yea, i had looked around the garage in what i had for spare junk laying around, but no dice. i could always just solder some leads on it and solder them to a relay terminal block and install any relay i need, but i'd like to do it the right way.

your picture is exactly the omron g2r-1 i referenced above. i would assume its just a 12v single pole single/double throw relay (spdt or spst). i doubt it pulls more than 10 amps, so getting a bigger g2r pcb relay would probably suffice. the g2r is also offered in sealed relays, which i would definitely prefer. I'm an electrical engineer, so soldering, using a meter, etc is childs-play for me, so i definitely wouldn't pay someone to do it. this is the kind of stuff nerds like me love to do, but the "work smart not hard" euphemism made me ask if someone may know the part number/manufacturer of the relay. i'm sure i can find something to make it all work, but i didn't know if anybody had a simple answer for the exact factory relay that was on the control board.

arob, Can you read any of the information off of either relay? Looks to me some of the information on the bottom relay ( in your picture ) is somewhat legible.

I found that for your kohler 6.5esz generator, the controller board is part number c-229388. I found a site ( old site, ) but it has the best picture of the board that I found so far. I can read some, but not all of the information on the relay. Perhaps with what you can read ( take a close up picture of the top surface of the relays ) and this photo, we can figure out what part it is.
Photo on this page -> http://www.generatorpanels.com/229388.asp

Also, searching found a few sites that will repair this board for about 100 dollars.

no, both relays are illegible. i was searching a few places for a relay board as well, but the ones for $100 look about the same condition as mine, and i don't know if i trust those relays any more than the ones i have. i did however see the repair for $89, which may be a possibility, but i'm 90% sure one of the relays are to blame. mine are in pretty sad shape, at least of top, but i don't think it will be readable even with a close up pic. i will be on the boat on saturday, so i will see if i can get a better picture for you. maybe you can see something i neglected.
 
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arob

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Pretty hard to read the model numbers of those relays. You might be able to get them to tell you the relay part numbers or sell you relays.
All said, $89 is a pretty good deal to "repair" your board..

Most relays are either 6, 12 or 24v coils. Those are probably 12v. All you would need to do is match the contacts etc...

Found that Omron relay on eBay for $7.95

And it looks like the other relays with the clear covers are also 12v


i thought about calling kohler, or one of the repair places to see if they would sell me a relay or two. i'd even pay a bit more than retail since they told me the correct relay to put in it. usually places like that are pretty stingy with their information, but would probably be worth a try. i'll have to give a few a call and see what i can dig up. i would agree that the coil is probably 12v, and the contacts are probably just a normally open single pole. i can't see it with everything still installed. i'm going to try to pull the board out this weekend and bring it home with me. once i can get it unsoldered, i should be able to do some probing with a meter and a few power supplies to test them and get some more information
 

HT32BSX115

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i thought about calling kohler, or one of the repair places to see if they would sell me a relay or two. i'd even pay a bit more than retail since they told me the correct relay to put in it. usually places like that are pretty stingy with their information, but would probably be worth a try. i'll have to give a few a call and see what i can dig up. i would agree that the coil is probably 12v, and the contacts are probably just a normally open single pole. i can't see it with everything still installed. i'm going to try to pull the board out this weekend and bring it home with me. once i can get it unsoldered, i should be able to do some probing with a meter and a few power supplies to test them and get some more information

Yeah, they usually don't want to reveal much for liability reasons (and they want to sell you another board!) Sometimes they hot-glue or "pot" everything to reduce vibration problems. Makes it pretty hard to 'fix' cold solder connections etc!

If you have CB desoldering tools, you can easily remove the other relays from the board and pop the covers off to get inside those relays. I wouldn't hesitate to wire any suitable relay where needed.
 

arob

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update. i pulled out the control board and started probing with a meter and a 12v power supply. it seems that the relay is working ok, but the pcb itself seems to be shorted. the one normally open contact is constantly shorted to ground. The contact on the Stop relay is where the short is located, so its working as long as its cranking, but as soon as you let go of start, the stop relay is shutting the gen set back off. I guess i'm going to have to buy another board....unfortunately.

fyi, the relay is a Schrack part number RP821012. Its a 12v coil with double pole, double throw relay contact.
 

mjf55

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arob, how do you know it is the pcb and not the relay. Are the coil contacts energized? Are the burn marks anywhere? With a little more trouble shooting / isolation maybe we can fix this thing.
 

arob

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i checked the contacts with the relay installed, and then de-soldered the relay and checked it again. the NO contact is still shorted to ground with or without the relay installed in the pcb. once the relay was removed from the board, the NO contact on the realay is now showing open. there are no burn marks on the pcb. it seems that one of the layers in the pcb must be damaged and is allowing two layers to touch each other.
 
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mjf55

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Agreed it is the board. I was hoping you cut cut a trace and make a wire jumper. I don't think it will be possible unless you can find the shorted spot, but with no visible indication, it would be shooting in the dark. Great job on the diagnosis.
 

CaleKee

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Hi..as per my knowledge this was a momentary ON switch like the start switch. I would hold the fuel pump switch ON for a good minute or more before I tried to start it. By doing this it was able to start and run with only a couple to three tries.
 
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