Forum Discussion

tpcollins's avatar
tpcollins
Explorer
Jun 17, 2017

What are my options for replacing my 22 year old gen set?

My boy who is an electrician at Ford and does a lot of programing for them, checked out my Onan 6500 propane generator tonight. With his oscilloscope he found that the "K2 relay was not being energized while running".

This is suppose to deliver 12 volts to the circuit board which says "ok to keep running" or something like that. He said there should be another set of bands on the armature that would require pulling half of the gen set apart (possibly with bearings inside) and looks like more work that both he and I want to undertake.

I'll call an Onan dealer Monday to ask about repairs but my boy said replacing it with a good used or new one might be a better option. The one I have is 6500 watts and runs on propane.

Anyone ever replace their propane generator using a different brand/model that worked out? Any help would be appreciated. Thanks
Class A
  • dr3x's avatar
    dr3x
    Explorer
    Jun 17, 2017
    I don't pretend to be an expert. So with that said my son and I have pulled his gen and it isn't hard to do and then had stator out and replaced bearings and back together in just a couple hours with a minimum of tools and effort. Not knowing your MH and gen location maybe it would be worth a look at for you and your son. Parts can be purchased at several different web sites or stick and brick locations.
    Believe me it would be much cheaper that way than finding a good used unit and then also how good is the unit you get. Just my 2 cents.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Jun 17, 2017
    I think I'd have the old one re-built.. ONAN's last a long, long time with proper care, and even when they fail, especially the failure you have. they can be rebuilt and are nearly as good as new. Though it is labor intensive, the job is fairly straight forward.
  • dougrainer's avatar
    dougrainer
    Nomad
    Jun 17, 2017
    The normal sequence for the K2 relay is a GROUND signal from the Oil pressure switch. NOT a 12 volt positive signal. There should be 12 volts on 1 terminal of the K2 relay. If NOT, then either a wire is loose or one of the fuses on the Genset is blown. OR the K2 relay is bad. The signal from the Oil pressure switch is indeed a safe to run signal. Your problem is a common oil sensor problem when "it runs when the button is pushed and held, but stops when released". OR you could have a bad oil pump,(not likely). All you have to do is GROUND the wire connected to the oil pressure switch. If the engine stays running and you DO have oil pressure, it is a bad oil pressure switch. Doug
  • KD4UPL's avatar
    KD4UPL
    Explorer
    Jun 17, 2017
    I'd fix what you have. This is truly a matter of "they don't make them like they used too."
    Most all used replacements you will find will likely be Onan. You may find a few Generac but I'd avoid those. Onan is a solid name and a good generator.
  • chuckftboy's avatar
    chuckftboy
    Explorer
    Jun 17, 2017
    I once had a LP gen in a 98 Newmar. While it worked great, it didn't offer a lot of run time between tank refills. This may be a good opportunity to install a diesel gen. In the 90's diesel generators were pretty noisy and that's why the LP units were often used but todays diesel generators are pretty quiet and offer a lot of run time connected to your tank.
  • RLS7201's avatar
    RLS7201
    Explorer II
    Jun 17, 2017
    Your old 6500 engine runs at 1800 RPM and the generator is direct drive. The newer Onan generators engines run from 2400 RPM and up and are belt driven generators at 3600 RPM. You may not like the resonance, in your coach, of the newer Onans. Also, some creativity will be required to mount a newer generator.
    Your problem may be as simple as burnishing (cleaning) the slip rings on the armature.
    There are some very informed Onan folks at the Smokestak forum that may be helpful.
    Look here for technical information.

    Richard

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