PowerTech 8KW generator runs 45 minutes and stops
Been chasing an intermittent failure of my 1997 IDL 8000FT 3 cylinder Izuzu 3LB1PV-02 1.12 L diesel generator. When it stops the overspeed/no speed error shows up on the ES52 control box as a steady (not flashing) error every time. This indicates overspeed, however, the generator is running and sounding normal when it dies, operating under a load with steady voltage and 60 to 61 HZ. It sounds like it has simply been turned off. It will generally run for 20 or 45 minutes before shutting down. Temperature as indicated with IR thermometer shows normal temperature, about 165 F at thermostat housing. I have had it shut down from high temperature due to a loose fan belt, bad radiator, and inadequate airflow around fan shroud. Then the error was "high temperature." All those issues have been corrected for several years. A fellow Foretravel owner walked by while I was testing my generator and said, "It sounds perfect." Then it just died.
I removed the PreHeat relay and swapped it with the Shut Down relay in the control box. No difference. I have disconnected and cleaned the fuel shut off solenoid and run resistance checks on both the start and hold in coils. The higher amperage start coil measured 2 ohms resistance, while the hold in side measured 36 ohms resistance. Searched around and found the resistance on a John Deer tractor solenoid is 2 ohms and 12 ohms, so my hold in resistance is 3x what a John Deer tractor specs out as normal. All my research indicates that the start side of the solenoid has low resistance, and the hold in side has higher resistance. Haven't found data on the proper range for the 3LB1 solenoid.
My best theory at this moment is that the hold in circuit of the fuel shut down solenoid is out of spec, and after it has been on for 20 to 45 minutes, it stops holding in and shuts the engine down. I did have one instance where the engine started and then immediately died on three separate sequential start sequences. That's a pretty classic case of a hold in malfunction on the fuel shut off solenoid. Of course the next day it started right up and ran for 45 minutes. It does seem to run much shorter if I try to run right after an ES52 indicated shut down with overspeed error.
If the fuel shut off solenoid hold in circuit breaks down, would the falling RPM from fuel shut off trigger an "overspeed" error in the ES52? I.E., RPM is out of range of normal operation while it falls to zero.
At the moment we are at the SKP COOP Ranch in Lakewood, NM where we recently purchased a lot. I would like to get this resolved before Quartzsite in January. I read Frank's generator saga while camped with Al at Gone Fishing Resort. It was a bad connection at the shutoff solenoid, which is why I removed my connector, cleaned it with Deoxit D5 and reconnected. The contacts looked like they would benefit from some cleaning.
The "work perfectly and then not" scenarios can be frustrating to diagnose. If 36 ohms is out of spec for the solenoid, then a new solenoid looks like the next step. One other possibility is that the AC to DC transformer that feeds the no speed and overspeed inputs on the ES52 could be going bad. Any help would be appreciated.
Topic: PowerTech 8KW generator runs 45 minutes and stops (Read 462 times)
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