Onan P-Series Ignition Module Replacement [Photos]

[BMW Phil 0]

20 hours ago, lynnmor said:

I believe that the insulator under the module is to lessen the heat transfer from the block, earlier models didn't have it but you should add one.  You can make one from gasket material.  You can download the Operators Manual and the Onan Service Manual here.  The troubleshooting methods will be in there.  The module is indeed grounded thru the mounting screws.  You can add a temporary line to to insure that 12 volts are getting to the coil.  Coils fail from heat much the same way as the module.  The trigger ring may be faulty, early black ones had more failures than the newer gray ones.  Be sure that you installed the flywheel key correctly.

That was my conclusion as well. I wondered how thick the insulator was, in case the sensors height in relation to the trigger ring was critical.

[lynnmor 9,043]

3 hours ago, BMW Phil said:

That was my conclusion as well. I wondered how thick the insulator was, in case the sensors height in relation to the trigger ring was critical.

I think the material is between .02” and .03 thick, it isn’t critical.

[davem1111 2,382]

Thanks to everyone who contributed to this thread. I'm going to be replacing one of these on a 416-H P216g this weekend.  The engine has been dying after 5-15 minutes when it gets hot (running time has gotten shorter and shorter).  Very frustrating problem. I'm hoping that this solves it. Also, I didn't spring for the OEM part at around $200 or more (almost as much as the tractor is worth at this point) - hoping that an aftermarket part will do the trick. The insulator tip is a good one also, @lynnmor.

 

The part and an appropriate puller will be here Saturday.  I tried rigging up a custom puller but it didn't work. I'm getting a steering wheel puller like @Duramax7man7 had suggested and shown in pictures. 

 

Just to be clear, the flywheel bolt should be loosened but left in, but turned out just a little so the flywheel can pop loose when applying the puller?  Any tips if it doesn't want to pop loose?  Somewhat gentle tapping on the backside of the flywheel?  (I know hammering hard could damage it....)

 

I had replaced the coil, regulator, condensor, and wires, and thought the problem was solved but it wasn't. Had the tractor sold to a neighbor but it came back after the problem kept happening and got worse. Unfortunately he no longer wants the tractor even if this fixes the problem - says he wouldn't trust it. 

 

Will let you all know how it goes.

[wh315-8 641]

I done this with my 520H a few years ago and haven’t had anymore issues. Replacing the 9 pin wire connector was a big issue because pins and wires were corroded which could be what caused the ign module to go bad. I was able to get a module and ring for around 140$. I also replaced the coil, plugs, condenser also.

the flywheel can be temperamental. A good solid hammer blow on the end of the bolt and spray lubricant on the crank helps. Figure a whole day to do the job, it takes so much just to get the flywheel cover off, nothing like on a Kohler K engine. And while you have so much off the engine, good time to check the valve adjustments.. Onan Service Manual in downloads if you don’t have it yet. 

12 minutes ago, davem1111 said:

Thanks to everyone who contributed to this thread. I'm going to be replacing one of these on a 416-H P216g…

[davem1111 2,382]

5 minutes ago, wh315-8 said:

I done this with my 520H a few years ago and haven’t had anymore issues. Replacing the 9 pin wire connector was a big issue because pins and wires were corroded which could be what caused the ign module to go bad. I was able to get a module and ring for around 140$. I also replaced the coil, plugs, condenser also.

the flywheel can be temperamental. A good solid hammer blow on the end of the bolt and spray lubricant on the crank helps. Figure a whole day to do the job, it takes so much just to get the flywheel cover off, nothing like on a Kohler K engine. And while you have so much off the engine, good time to check the valve adjustments.. Onan Service Manual in downloads if you don’t have it yet. 

 

Ah yes, thanks for mentioning the 9-pin.  I'll check that out also.  Valves are a good suggestion too.

 

I already have the flywheel shroud off. I'm more worried about getting all that back together properly. 

[wh315-8 641]

5 minutes ago, davem1111 said:

 

I already have the flywheel shroud off. I'm more worried about getting all that back together properly. 

It can get tricky, I have 3 Onans, if you get in a bind and need pictures of where things go, don’t hesitate to ask. I will be happy to help as I can.

[Bill D 3,164]

Having done a couple of these modules myself you can save a step if you're patient.   You can get a 5/16" box end wrench under the stator to remove the screws holding the ignition module.  This will save you from having to remove the stator.  Clean everything well with electric motor cleaner and compressed air before reassembly.  Changing the module should fix your issues. 

[lynnmor 9,043]

12 hours ago, davem1111 said:

Just to be clear, the flywheel bolt should be loosened but left in, but turned out just a little so the flywheel can pop loose when applying the puller?  Any tips if it doesn't want to pop loose?  Somewhat gentle tapping on the backside of the flywheel?  (I know hammering hard could damage it....)

 

The flywheel bolt is loosened a turn or two so that it will keep the heavy flywheel captured when it pops loose, just be sure that the puller doesn't turn the bolt back in as you turn the puller bolt.  I won't use a two bolt puller due to the extreme force on just two.  You can hammer on the puller bolt to help with breaking it loose.