520-H Ignition Trigger - Replacement

[Flat Thunder Channel 178]

Hello everyone!  I am going to replace the ignition trigger on my grandfather's 520.  Any tips, tricks or important things I should know before starting?  I already have the parts.  I just need to tear into it.  

 

I didn't know Cummins owned Onan.

[WHX?? 50,401]

55 minutes ago, Flat Thunder Channel said:

I didn't know Cummins owned Onan.

Yeah for a few years now... they wanted a piece of Onan's genny action I think. 

 

Change out is pretty straight forward. Quite a few threads on doing it here. Some may suggest taking a look at the governor as long as the flywheel is off. 

here's a manual if you don't have one. 

492-4006 Onan P216 P218 P220 P224 SM.pdf

[lynnmor 7,536]

Onan started using a gasket like material under the trigger, if it doesn't have it, I would add it.  Some think it is to reduce heat transfer.

 

You may need an impact wrench to remove the flywheel bolt if the tractor was exposed to water too many times.  I only had one that was frozen like that, the threads fought all the way out.  Clean the bolt and crank threads and make sure the bolt threads in easily with your fingers, I had to run a tap in on the frozen one.

 

Watch how the flywheel key is installed.  Clean the crank and flywheel thoroughly using 600 grit paper or crocus cloth, torque to 55 lb. ft.

[Flat Thunder Channel 178]

Thanks for all the information!  I wasn't overly worried, but sometimes getting others perspective is helpful / time saving.  I downloaded the manual for future reference too. 😁

[Flat Thunder Channel 178]

I fixed it!  Check out the repair video if you are interested in replacing a ignition module (crank trigger) on a 20 HP Onan.  The video illustrates the symptoms it experiences in real life.  Hopefully it will help others diagnose problems on their 520 Wheelhorse.  Dad and I struggled to identify this problem.  We never made it a priority and the problems it experienced were similar to a fuel delivery issue.  I am happy to say she is back in action!!!  Go team Wheelhorse!    520 HP WheelHorse; Engine Repair

 

 

[tom2p 2,394]

Nice job !

 

( commented in other thread )

 

[Pappy 4430 8]

Can you give me those part numbers please ? Can't read the trigger number.

 

Thank you very much

Edited April 17, 2021 by Pappy 4430

[Flat Thunder Channel 178]

20 minutes ago, Pappy 4430 said:

Can you give me those part numbers please ? Can't read the trigger number.

 

Thank you very much

 

166-0785 & 166-0767

[Pappy 4430 8]

7 minutes ago, Flat Thunder Channel said:

 

166-0785 & 166-0767

 

Thank you very much sir ! 

 

I have same problem with my 520-8

[Flat Thunder Channel 178]

18 minutes ago, Pappy 4430 said:

 

Thank you very much sir ! 

 

I have same problem with my 520-8

 

You are welcome!  Happy wheel horsing! 👍

[Shippey 2]

I know this post is old but wanted to pile on and say this video was outstanding.  I used it to fix my 520H.  I'd like to add a couple of notes and hope Flat Thunder doesn't mind.  First, when I went to order the parts I saw a note suggesting to order the rotor first as this was most often the problem.  The rotor was about $35 and the igniter about $140 so I thought I'd take the suggestion.  Turns out they were right.  Just changing the rotor solved the problem.  FYI since it was a little laborious to take apart and I thought it would be more so to put it together, I ordered the igniter anyway.  As it turns out, there was a 2 week delay to ship it so I put it together with the rotor only and cancelled the igniter after the problem was solved.

 

Second, the fly wheel cover comes off, and more importantly, goes back on if you take the regulator off,  It's the piece FT struggled with a little getting the fly wheel cover off.  It's only a short 3/8" head bolt and if you can keep from bending the sheet metal taking the cover off, it's a lot easier putting it back on.

 

Thanks Flat Thunder.

[lynnmor 7,536]

3 hours ago, Shippey said:

First, when I went to order the parts I saw a note suggesting to order the rotor first as this was most often the problem.  The rotor was about $35 and the igniter about $140 so I thought I'd take the suggestion.  Turns out they were right.  Just changing the rotor solved the problem.

 

Was your rotor black or a light gray like the one shown in the first post?  Usually the newer light gray ones had fewer problems.

[Flat Thunder Channel 178]

4 hours ago, Shippey said:

I know this post is old but wanted to pile on and say this video was outstanding.  I used it to fix my 520H.  I'd like to add a couple of notes and hope Flat Thunder doesn't mind.  First, when I went to order the parts I saw a note suggesting to order the rotor first as this was most often the problem.  The rotor was about $35 and the igniter about $140 so I thought I'd take the suggestion.  Turns out they were right.  Just changing the rotor solved the problem.  FYI since it was a little laborious to take apart and I thought it would be more so to put it together, I ordered the igniter anyway.  As it turns out, there was a 2 week delay to ship it so I put it together with the rotor only and cancelled the igniter after the problem was solved.

 

Second, the fly wheel cover comes off, and more importantly, goes back on if you take the regulator off,  It's the piece FT struggled with a little getting the fly wheel cover off.  It's only a short 3/8" head bolt and if you can keep from bending the sheet metal taking the cover off, it's a lot easier putting it back on.

 

Thanks Flat Thunder.

 

No problem!  I glad it helped out on the repair process.  Thanks for watching 👍😁

[Shippey 2]

The old rotor and the new rotor were both light gray.  But there's an update.

[Shippey 2]

I need to update my post above.  Specifically, "when I went to order the parts I saw a note suggesting to order the rotor first as this was most often the problem.  The rotor was about $35 and the igniter about $140 so I thought I'd take the suggestion.  Turns out they were right.  Just changing the rotor solved the problem".  Turns out it didn't solve the problem.  I replaced the rotor only in early Oct 21, when it was still warmish, and the 520H ran as it should.  So I parked it and waited for the snow.  When I went to use it in the cold of Jan 22 the shutdown problem returned.  In fact it was worse since it would only run for about 5 minutes when previously it would run for almost 10 before it shut down.  I ordered the ignition control from Jack's Small Engines which cost $163 with shipping.  Worst part was it took a month to get it.  I put the ignition control in and have run it for about an hour in 15 degree weather and so far so good.  It's parked again and waiting for snow.

[Handy Don 13,225]

12 hours ago, Shippey said:

I need to update my post above

Thanks for adding the extra post.

Supporters are able to go back and edit their earlier posts for up to, I think, 30 days. After that, depending on importance, you can ask an Admin to make the change. Non-supporters can only edit their previous posts for, again I think, 48 hours.

[Flat Thunder Channel 178]

  I wouldn't change one without the other simply because it's such a time intensive process.  Glad you got it fixed up!

 

  This was one of the most difficult faults that I had to diagnose on grandfather's tractor.  Cheers,

[RonnieB2nd 33]

What's the problem? Trouble starting?

[Shippey 2]

Started fine but would only run 4-10 minutes and shut down like I turned the key off.  Had to wait 45 minutes to restart.

[lynnmor 7,536]

Temporarily, run a jumper wire from the battery + to the coil + and see if the problem continues.  Of course only use the jumper while actually testing.