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HoosierDaddy
06-01-2008, 02:13 AM
12.5 kw kohler/perkins 1978 Newell. When I tried to start the generator this spring it just would not fire. I have been chasing fuel problems for 2 weeks now. Even R/B the lift pump. Today I'm finally getting some fuel dripping from the injector lines but then the generator quits cranking. Its dead... apparently no 12v at the no.3 terminal on the control box circuit board (the power that goes to the remote switch at the instrument panel) The fuse on the back of that panel in the control box checks OK...it has 12v in and out. If I manually trip the relay (CR) on the panel it will crank. Is there another fuse that I'm missing? Thanks, Dean

fulltiming
06-01-2008, 02:25 PM
Dean, the manual lists two fuses: a 10 amp fuse on the relay controller (typically next to the Preheat/Prime Switch and an 8 amp fuse located in the end bracket assembly or junction box. The engine should crank, but not start if the 8 amp fuse is blown. If the 10 amp fuse is blown, the engine will not crank. The junction box is the large box directly behind the fuel filter and the end bracket assembly contains the connector and the automatic voltage regulator near the junction box.

You might replace the 10 amp fuse even though it is showing voltage across it. Sometimes a fuse element will develop a slight fracture and show no load voltage but will fail to pass load current.

Looking at the wiring schematic, power from the battery goes directly to the starter solenoid, then from the starter solenoid to the air heater relay, then into terminal 1 on the connector at the rear of the controller, then to the connector strip (position P, next to 1) inside the controller then to the 10 amp fuse. You might want to confirm that the connections are good and clean at the solenoid, the air heater relay and that the contacts on the connector strip in the controller on both sides of terminal P are clean and tight. You could try a jumper from the each side of the rear of the 10 amp fuse to the trigger on the starter solenoid to verify that you have power coming into the controller and to verify that the fuse is good.

You should also be getting more than just a little fuel dripping from the injector lines.

Let us know what you find and we will continue to track down your problem.

fulltiming
06-01-2008, 02:29 PM
As a further thought, if you can start by jumping from the fused side of the fuse unit to the trigger on the starter relay, the potentially the ground is being broken by a defective low oil pressure switch or a defective high temperature switch.

HoosierDaddy
06-11-2008, 02:54 AM
Here's what we found: A small piece of rubber had lodged in the fuel line between the lift pump and the filter....causing the initial fuel starvation. After repeated cranking the starting system went dead. There is a re-set switch on the back side of the control box which is not normally visible. After resetting the generator would crank again. We put new rubber seals on the fuel lines and installed a new lift pump and starter motor and it's good to go. (Actually feeling my way through all this was much more involved than I can describe!!!)
Thanks for the help, Fulltiming!!!
Dean

fulltiming
06-11-2008, 03:58 AM
Glad you got to the root of the problem. Thanks for updating us. I will remember to add those fuel lines to my list of needed updates.