05-30-2018, 06:41 PM
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
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