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HD90 MKIV drill wiring

MrMajestical ยท 2016-05-23 23:43

Troubleshooting a HD90 mark IV drill electrical issue. Engine will not start. The hour meter doesn't work, so that being the trigger for a relay that triggers the fuel lift relay, I am wondering if this is an issue? Also the fuel pump doesn't work, I ran a series of jumpers to supply power to the fuel pump, and a couple other things and it started. I have a wiring diagram but it doesn't show some things that are on this equipment, like a solenoid on the bottom of the injector pump, and what looks like a temp switch on the left side of the engine that is wired to this solenoid. And info on how to fix this would be appreciated.

Replies3
  1. #1lantraxco2016-05-23 23:47

    Temp or oil pressure switch?

  2. #2MrMajestical2016-05-24 00:51

    I called a dealer and a tech there did say that the temp switch would go out and it was a known issue with this machine. I have spent dozens of hours troubleshooting this thing. I guess I need to pull every electrical component and test it. Another issue is there is no horn switch, which is wired into the emergency shutoff switch, so I'm wondering if that's a problem. I think it is a combination of several things. I know it will run, but it figuring out what's wrong w/o throwing hundreds of bucks in parts on it.

  3. #3charleseccles7@2016-05-24 01:25

    Hello Please visit the site http://www.reliable-store.com . It would be help you for solving your problem.They have all service and repair manuals and clear pictures for you.