Forum Discussion

LI-Camper's avatar
LI-Camper
Explorer
Jul 30, 2013

Locate Onan oil sensor switch

I have an Onan 4kw generator on a 2004 Jayco Greyhawk. It is a 4KY type gennie. I am experiencing generator shutdown after running about 15 - 30 minutes. This is with or without load. I would like to check the oil sensor but can't find it . It does not appear to be on the right side as my diagrams indicate. Could it be in the oil pan? Besides the oil sensor my next culprit would be the fuel pump. Any suggestions would be helpful.
Class C

10 Replies

  • j-d's avatar
    j-d
    Explorer II
    Aug 01, 2013
    Glad you have it running! Thanks for letting us know what worked. So often, the OP doesn't give us an update.
  • LI-Camper's avatar
    LI-Camper
    Explorer
    Aug 01, 2013
    Got the new fuel pump installed this morning. The generator ran for half an hour without any issues. Thanks for all the suggestions. We leave for Niagara Falls this Sunday.
  • LI-Camper's avatar
    LI-Camper
    Explorer
    Jul 31, 2013
    Thanks for all of these suggestions. When the generator quit last time after running 14 minutes, it wasn't getting any fuel. This is after replacing the fuel filter to see if that was a cause of the problem. Looks like the fuel pump is the problem. I'll report back after the pump is installed.
  • Steele_Grey's avatar
    Steele_Grey
    Explorer
    Jul 31, 2013
    If you recently added oil, it could be overfilled. This happened with me once when I topped off the generator and it would die after 12-15 minutes. I drained some oil out till the dipstick showed a bit below the full mark and it ran for hours without a hiccup.
  • _40Fan's avatar
    _40Fan
    Explorer
    Jul 31, 2013
    It is that time of the year again. Voltage regulators are way too common.
  • CloudDriver's avatar
    CloudDriver
    Explorer
    Jul 30, 2013
    Had the same symptoms with our 4KY Onan a couple of years ago. Turned out to be the fuel pump.

    Your generator should have a "prime" function on the start stop switch at the generator itself. When the generator shuts down by itself, hold the prime side of the switch to see if you can hear the fuel pump running. It makes a buzzing sound. No sound = new pump needed.
  • TyroneandGladys's avatar
    TyroneandGladys
    Explorer
    Jul 30, 2013
    We had similar issue at campground one time and it was from overheating. Left compartment door open problem solved.
  • LI-Camper's avatar
    LI-Camper
    Explorer
    Jul 30, 2013
    Thanks, J-d. I put in a call to a Onan distributor and that's what they told me.Now I have to determine why the generator stops after running for 15 - 30 minutes.
  • j-d's avatar
    j-d
    Explorer II
    Jul 30, 2013
    L-C, it's a better Tech Issues Forum question.
    I don't have the details but I understand that somewhere in the evolution of the KY series, ONAN discontinued that sensor. Somebody over there (or on smokstak.com) could tell you, but you may be looking for something that's not there. It depends on the Spec Code of the generator.
  • Mich_F's avatar
    Mich_F
    Explorer
    Jul 30, 2013
    My 97 4K wouldn't skip a beat if it just sat on level ground. When I drove it on any incline or went around a corner it would die. The problem was the low oil shut off, which in my case was in the pan. My repair shop just disconnected the wire or wires from the sensor and I haven't had any problems since.

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