Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Command CH18 s magneto gap?


hurleyii

Recommended Posts

Ok guys so I cleaned engine completely . Pulled flywheel and all. No wonder it had charging issues the main seal was shot. Replaced and need to set gap on magneto now.

The magnum in the Duetz said right on the Magneto .042. The Magnum I did last week did not and per Kohler website it was supposed to be installed at .018 and after torq down should be .012-.016 . I can’t find a book on the Command on Kohler website nor have I been able to find on hear what I should set it on. No topic in search about gap . Lots of diagnostic and install from coil ignition but no luck on gap . 

So I set my gap to .016 with a final check of .014 . Is this correct or do I need to change it.

Thanks for all the help guys and gals. 
Soon as that’s done I can assemble shields and stat my frame modding for the command. 

Link to comment
Share on other sites

 

29 minutes ago, hurleyii said:

I can’t find a book on the Command on Kohler website nor have I been able to find on hear what I should set it on.

 

 

Looks like it's 0.012" per the Command Service Manual: 

image.thumb.png.aab7baea19e28908dee0c446fb1d2cab.png

Above is from:

image.png.3b6d9c3d8f22a3aabfd0be7db64055a3.png

 

There's a version available in the Downloads Forum:

https://simpletractors.com/files/file/59-kohler-ch-engine-repair-manual/

 

Link to comment
Share on other sites

Loose coil pack / magneto, business card between them and the magnet, tighten it up, rotate the flywheel a bit and pull the card.  Perfect, every time.

Link to comment
Share on other sites

19 minutes ago, Brettw said:

Loose coil pack / magneto, business card between them and the magnet, tighten it up, rotate the flywheel a bit and pull the card.  Perfect, every time.

I've used that method on several Briggs single cylinder engines and it's worked fine.  

Any clue why Kohler seems adamant about not using a business card?

From step 4, above:

image.png.826daa234eb2dc6947998d86c6b6ba4b.png

Link to comment
Share on other sites

It's called air cooled engine trying to survive 87 octane . The larger the gap the easier for predetination or misfire. This mistake cost me 7,000 dollars on a forced performance engine.( That was just the top end damage. )  I melted one piston in half and a second in 1/4.( I bought a used sb) My mistake was many but after I rebuilt it I found out very quickly that the gap is very important on proper ignition burn. There's a very large difference between running and properly running . Your gap effects spark temperature. Improper temp can cause premature or late ignition. Premature creating overheating which will melt pistons , late ignition will cause fuel wash down and power loss. Both are deadly to the engine.

My cylinder head on the engine I blew looked like someone took a plasma cutter to it for micro seconds at a time. My car now has 4 additional computers to control it's ignition and boost system. If there's any predetination my check engine lite now flashes. The gap on the plugs is so tight a dollar bill won't fit thru them. 

I have a K301 10hp head in a scrap pile that looks the same . Most of you would call it a K241 . However the block says 301.

Link to comment
Share on other sites

12 hours ago, PhanDad said:

Any clue why Kohler seems adamant about not using a business card?

This depends on what version(s) of magneto pack is installed on a Command. Kohler has had several revisions of the ignition systems and replacement packs since the days of the Sovereign Command.  Some required something like a precise gap and others did not.  Depends on the packs installed.  They are not mix and match.  Different packs must be replaced in pairs. There are several service bulletins on the various systems.  None of them affected the plug gap.

Link to comment
Share on other sites

11 minutes ago, rbstuartjr said:

So should we replace coils in pairs when one  goes bad then?

Always, it’s like changing a shock or brakes. If you can get the exact same part number then maybe not but even that’s questionable and coil would require testing. If we can ohm it out and test voltage draw on firing sequence and as I never became a master tech that’s far above my pay grade as to what can actually be tested or most of the how. But it would need to having matching test results technically. Basically would need to find out how it tested before it’s shipped from plant. Which probably happens once every so many times per amount produced. Then one could test new and have working parameters to test old . ( that last sentence is assuming new is slightly out of spec but having what OEM wants to see would give an idea if the new and old are compatible. )

There is also the fact we are talking about a lawn mower engine. I buy mine for 100-300. Then there is also the fact that Horizontal engines in 10 years is gonna be as rare as our tractors are to find in good condition. Not even ZT tractors are using them much these days.

Link to comment
Share on other sites

The commands I have are from the 90’s with original coils. Those coils have been superseded with different part numbers. I guess with pulling the engine and getting the shrouds off, it makes sense to replace both if one of them goes bad.

Link to comment
Share on other sites

Now your thinking . With that said I’ve now ripped enough engines out I believe a spring engine removal will be being added to my maintenance list for my tractors.

Link to comment
Share on other sites

10 hours ago, rbstuartjr said:

So should we replace coils in pairs when one  goes bad then?

If you can't locate the same part number pack new or in the used market, you should replace both and get the latest rev.  Kohler has 'conveniently' supplied kits (including a needed wiring harness) for the conversion.  I have seen the kits on eBay. I haven't had to replace a pack recently but then they looked different (but no more so than being from different vendors for the same PN).

Link to comment
Share on other sites

2 hours ago, CarlH said:

If you can't locate the same part number pack new or in the used market, you should replace both and get the latest rev.  Kohler has 'conveniently' supplied kits (including a needed wiring harness) for the conversion.  I have seen the kits on eBay. I haven't had to replace a pack recently but then they looked different (but no more so than being from different vendors for the same PN).

Here is the pics of mine. Not sure if that number is good enough to find specs or not.

IMG_20210321_100758.jpg

IMG_20210321_100753.jpg

Link to comment
Share on other sites

A couple of digits have disappeared but fortunately they are the first 2.  Kohler Command twins unique PN's generally start with 24. sm01  The complete PN is 24-584-01.  With that PN (and spec #?) OPEengines.com will identify the later rev's.  Used to be able to figure out the original PN on the Kohler website.  I haven't been there recently.

Link to comment
Share on other sites

57 minutes ago, hurleyii said:

So your saying these modules have a defect and fail??

That’s my understanding. When the modules age they start to fail when hot.  It starts as an intermittent problem and gets worse.  I haven’t experienced the problem personally.  

@steve-wis comment from above linked post:
“With both of the original modules, I had good spark on right bank, weak on the left when cold and none on the left as it warmed up.”


I wasn’t aware of the issue when I installed the above pictured Command in 2014. It’s been running fine since then, but the engine doesn’t get many hours. 

Edited by PhanDad
grammar
  • Like 1
Link to comment
Share on other sites

2 hours ago, hurleyii said:

So your saying these modules have a defect and fail??

Everything can fail.  Not everything will fail.  It's almost always a question of 'how often', not 'defect'.  Kohler's requirements for unacceptable failure rates were exceeded so they revised the design.  Like Bill, I have that PN pack in some of my Kohlers with no failures.  I have upgraded others.  Each of us trades that off differently.  My thoughts are that if you are going to change one (for whatever reason), you should upgrade both to the latest rev.  That's mainly because I don't want to do the job twice.

  • Like 3
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...