[Quirkrjiii]

After 15 years of flawless performance, our 12.5kw Kohler has just shut itself down for the first time. I'm certainly looking for suggestions.


     Travelling from D.C. to Elkhart, Indiana and 50 miles before arriving at our destination, our generator stopped running. Since that happened last Sunday, I have been reading the manual, troubleshooting the genny, talking to the great folks at Newell Coach, and calling Kohler dealers. Here's what I think I know at this point: When I push the switch to the start position, the generator turns over and fires up. That is: the engine is running. As soon as I release the switch, the engine dies. The fuel solenoid engages and remains engaged for as long as I hold the switch in the start position. If I physically hold the fuel control lever (attached to the fuel solenoid) in the engaged position and release the start switch, the engine continues to run. However, the generator does not produce electricity. At no time does the blower fan come on, nor do the AC appliances work.

     Other details: I have checked the 10 amp fuse on the controller, and it has continuity. I can't find the 8 amp fuse that the manual states is located in the "end bracket assembly". In fact, I don't know where that assembly is. The fact that the fuel solenoid disengages as soon as I release the starter switch could indicate that the engine shutdown mechanism is causing the problem. It seems that there are three components to the shutdown mechanism. They are: a low oil pressure switch, a high coolant temperature switch, and a switch that causes shutdown if the halon fire extinguisher is inoperative. I have detached the wires attached to the fire extinguisher and tied them together and that did not fix the problem. I have not yet tested the other two switches and am not sure how to test them. Finally, the oil pressure gauge on the dash has been a bit undependable right along; so I can't be sure it is giving good readings. It typically shows a pressure for a time, and then cuts out completely, going to zero. At the present, it is sitting at about 38 pounds even with the generator and the coach ignition off, and that reading doesn't change when I attempt to start the generator or turn the ignition on.

     Tomorrow morning, we are driving the coach to a Kohler service facility in Byron Michigan (Michigan Critical Power). they have graciously deferred their scheduled work to the afternoon in order to look at our generator; but they are not familiar with this old model, not confident that they can fix it, and don't have parts. Another facility in Chicago (Illini Power Systems) has suggested beginning by checking the starter solenoid. They state that I should check the three wires connected to it. One will be ground, one will be hot when I engage the start switch, and the third will go hot when I release the start switch but the engine is running. If it works in that way, then they suggest the problem is with the fuel solenoid itself, because it is receiving the necessary power to do its job. If those two hot wires do not act as described, then the engine shutdown system is killing the engine, and further investigation should focus there.

     I am looking for any recommendations on how to proceed: how to continue the troubleshooting to include how to check the low oil pressure and high coolant temp switches. No one has been able to advise on why the generator is not producing AC power.

     Any help would be appreciated.

Dick Quirk

[bestgenman]

Your problem is likely there is no output from the generator.  The control looks for AC from the generator and without it, it shuts down.  

I would suggest you ask your service technician to look at the voltage regulator or the brushes.  You have not stated the hours on this set or when it or even if the brushes were checked.  The key here is that your cooling fan is not running.

Parts are readily available for this set even though it has some age.

[Quirkrjiii]

Your problem is likely there is no output from the generator.  The control looks for AC from the generator and without it, it shuts down.  

I would suggest you ask your service technician to look at the voltage regulator or the brushes.  You have not stated the hours on this set or when it or even if the brushes were checked.  The key here is that your cooling fan is not running.

Parts are readily available for this set even though it has some age.

Thank you for your advice. We will suggest that to the tech tomorrow. I do appreciate your help.

Dick Quirk

---

Your problem is likely there is no output from the generator.  The control looks for AC from the generator and without it, it shuts down.  

I would suggest you ask your service technician to look at the voltage regulator or the brushes.  You have not stated the hours on this set or when it or even if the brushes were checked.  The key here is that your cooling fan is not running.

Parts are readily available for this set even though it has some age.

Thank you for your advice. We will suggest that to the tech tomorrow. I do appreciate your help.

Dick Quirk

I've replaced hourmeter once. Not knowing what i don't know about the previous owner, it appears that the generator has about 4500 hours on it.

[ccjohnson]

Sounds similar to our experience. We took ours to Lofton equipment in Phoenix, AZ. They are a servicing Kohler distributor. They replaced the slip ring & brushes. It would still not make power. They replaced the control board with used ones off work bench a couple of times to no avail. They made several phone calls looking for advice. Finally the tech was able to find the problem. A spade connector in the control box was cracked & broken. It had been taped together with electrical taped by some PO. We were very grateful that the tech there had the patience and determination to stick with it until we finally had power about an hr after closing time.

[MrE]

It could also be the squirrel cage cooling fan, if it's not working the generator won't stay running either.

[oldmansax]

The Wanderlodge Owners Group board has just about any info on the Kohlers that you would need including all manuals and parts lists, trouble shooting and complete rebuild with pics if needed. I have had two Kohlers and here are a few things I found out the expensive way.

The Perkins 4.108 engine will run longer than you will ever need it providing it is maintained; the generator head, not so much. Early Kohler generators bought the heads from the cheapest supplier. That lead to there being multiple changes even in the same model year, sometimes in the same model week! Known failures are rear bearing (resulting in stater and armature damage), voltage regulator ($350) diode array ($300+) control box wiring/components ($??) etc. The rule of thumb is if you have to spend more than $500 total, replace the head, Central Georgia Generator is our friend. About $1300 for a new tech brush less head. Bolts right up. Clean reliable power probably for as long as you own the coach.

One more cautionary tail. One guy on WOGGERS board is a stickler for ALL ORIGINAL on his 1985 model coach. He has both the skills and the facility to do things right. He spent $4000 ( not including his labor) before he gave up and installed a new head.
YRMV Good Luck!

TOM

[Quirkrjiii]

Thank you all for your advice. It needed new brushes, springs, and holder. The brushes were totally worn out, and the holder was damaged, probably by what was left of the brushes.

From Elkhart, Indiana, we looked for a knowledgeable Kohler service facility. Most were backlogged with work. After many phone calls, we happened upon John Maher at Michigan Critical Power Systems in Byron Center, which is near Grand Rapids. He alone was willing to push his other projects back to get us fixed in a reasonable time. He quickly isolated the problem, ordered the parts: all of which were still available from Kohler, and, coming in on a Saturday, got us operational within only two days. He also cleaned the rings, which were otherwise in good shape.

To gain access to the generator head without dismounting the unit, John removed the Dayton blower from the front, right side compartment, and worked through the square opening into the hush box. Considering the age of the unit and the difficulty in access, we had him go ahead and replace the voltage regulator as preventative maintenance.

We highly recommend John and his company.

Again, thank you all for pointing me away from wasting hours on the engine.

Dick and Maura Quirk

[ccjohnson]

On our '92 there is an access panel that can be removed directly behind the generator compartment. This provides access from underneath the coach.

[ccjohnson]

As an add on to this post and another, sometimes there are zebras! Last night we stopped to eat at Railroad Pass outside of Vegas. We left generator on and a light on inside coach. When we got back generator had died. Started it up and it ran for a short time then died. "dirty fuel filter" I exclaimed. We ran into Kingman with no generator. Got to TA at 1 am. They did not have filter but could change it in an hr if I had one. Could not find my spare. Dry camped at TA. Called Speedco at 7 am. They are changing out filter vendors & did not have that one in stock yet. Called NAPA they had 4 in stock. I bought 3. Went back to coach & slid out generator to change filters. What a surprise! The v-belt had broken. I grabbed my trusty spare belt, wrong size. I had gotten spare for Dayton blower. Searched around & found generator spare I had intended to put on last year. Didn't change last year because I did not want to slide radiator forward to make the repair. Also found my spare fuel filter. Now I have 4 spares and put them all in filter storage area. Had I taken the time to make sure it was horse hoofs instead of zebras, (slide generator out & look before going for parts) I would have saved some time & cash. It is also nice to know that high temp safety shut off is working! I did change the v-belt btw.