Jump to content

ONAN P220 on 520H won't start

Recommended Posts


Well, I put the washers on the flywheel side of the engine and that seems to be working better as far as the starter to flywheel, but the engine won't start. I have a new coil, condenser, plug wires, plugs (not sure about the correct gap though), and a new electric fuel pump with filter. The mower ran one time and mowed the yard a month ago but has not started since then. It started one the first crank when I put all that in new. Is it possible the coil has failed? I even put the old plugs back in to see if that was the issue. The were not burnt. What should I check to test possible failures of the coil or fuel? I think the fuel is going to the carb but not sure if this is enough pressure? Not ready to give up yet...

Share this post

Link to post
Share on other sites

I had similar problems with mine and got it fixed :banana-wrench:Check some of these threads and it may help you:


Download these manuals:


Let us know if you have any more questions there are a lot of knowledgeable people here who are glad to help :)

  • Like 1

Share this post

Link to post
Share on other sites

I used a Match Book to set air gap

Also if the Magnets are rusty it wont create a spark

They say that the carb gums up fast on a onan, remove the fuel line at carb and crank engine, if you have fuel the carb float may be stuck

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • lsc1257
      By lsc1257
      I have a 1996 520H Wheel Horse for sale.  The tractor has just over 800 hours on it.  It comes with a 48 inch deck.  The deck is a 1995 and has over 1,500 hours on it, as it came brand new with my 312-8 that I sold several years ago.  This 520-H has the swept front axle so it can handle a 60 inch deck.  I just replaced the battery and the deck belt this summer.  The engine is a 20HP Onan and it starts right up but requires the full choke.  The transmission is an Eaton 1100-062, hydrostatic.  The deck is in rough shape but the spindles appear to be in good working order.  The right rear tire has some cracking.  The original operator's manual for the 520H is included, as is the original operating and maintenance instructions for the deck, plus the installation instructions for the deck.  Also included is a new PTO belt and several miscellaneous deck wheels and rollers.  Additional pictures available upon request.  Asking $500.

    • Joe Warren
      By Joe Warren
      Onan model BF-MS2425A Engine for parts. This engine pulled from NOS Bolens QT16 tractor that sat for 40+ years. Engine has less than 25 hours on it. Engine currently stuck. Local pick up in  Easton  MA.  $49  or offer.

    • Joe Warren
      By Joe Warren
      Wheel Horse
      Service Tool Kit
      Onan Industrial Engines
      Kit is missing oil filter tool, otherwise complete. Tools in excellent condition. Small crack in plastic case, bottom, middle. 
      $129 plus shipping cost.
      Message me if you are interested in purchasing. Thank you. Joe

      By SPINJIM
      1992, Wheel Horse 520-H.   Onan overhauled: New rings, cylinders honed, valves lapped, new carb., new seals and filters, new fuel lines and primer bulb for easy starts.  Seat is like new.  Front tires are new.  All tires hold air.  Some repainting, but didn't need much; was stored indoors.  New decals.  Other new parts.
      Has swept front axle and Variable Ratio Steering.  Belt cover ventilated to cool back cylinder.  Rear wheel weights are 55 lbs. each.  

    • odee61
      By odee61
      Will the PTO work from the 312 Hydro with a 12 hp Kohler onto the 416-8 Onan?  My PTO disc went today. Any help would be most appreciated.
  • Create New...