austinyazookees
Member
- Joined
- Jul 3, 2019
- Threads
- 3
- Messages
- 15
Hi all. New to forum. But reading some of the threads here, I think I've finally come to the right place for some answers about fixed ignition coils.
I have an old (as in 2000ish vintage) Yazoo Kees ZTR with a Kohler CH25 V twin engine with a fixed timing ignition system, i.e., no SAM.
I bought it a while back from a mower repair guy outside Waco (I'm in Austin, about 100 miles away, saw it on side of road while driving back from Dallas, bought it on a lark). Repair guy had modified it with a push button starter after the ignition switch starter mode failed (though "on" position still works to power the harness), so wiring harness has been modified (the oil sentry oil pressure sensor on the breather has also apparently been disabled/bypassed as well but not the oil level sensor).
The tanks totally clogged up, but have since rebuilt the entire fuel delivery system. New tires all around as well. Replaced the main seal and rebuilt the breather (as I was thinking the main seal oil leak was caused by pressure blow from a broken breather reed). So I am vested in the ZTR now.
It's served me well for almost a year.
Cranked it up after sitting the winter to cut an acre property I have. It ran a bit warming up (with help from some starter fluid to get it going), then it suddenly stopped running, so checked the three things an ICE needs: compression, fuel, spark.
Compression and fuel are good, but spark appears inconsistent: weak to non-existent, both using a tester (automotive -- the HFT in-line spark type with a very faint orange light) and directly thru the grounded plug (sometimes a spark, sometimes not).
I want to replace the coils first and see if that is the issue, but apparently Kohler doesn't offer the simple single blade coils for the fixed ignition system on the CH25 anymore: instead, Kohler makes an ASAM/MD (something speed something module / magneto discharge?) retrofit kit (24-755-308-S) that includes new 2 blade coils, some new harness wiring and a new flywheel/magneto -- and is priced accordingly, i.e., expensive.
I am not too motivated to go retrokit and replace the flywheel (yet), so I would like to see if I can find some aftermarket coils that are compatible (even if they requires modification like rewiring or an additional resistor in-line) with the CH25 fixed ignition setup.
I've read about some aftermarket coils that work with some modification -- two specifically, one suggests adding a 4K ohm resistor in-line to get the coil resistance up-to-spec, and another suggests just disconnecting the kill ground wire to the coil altogether and just letting the carb fuel cutoff shut down the engine.
I'm looking for anyone who has the same system and has found some coils that will work -- even with some modification.
Thanks in advance for any help you might be able to provide me.
I have an old (as in 2000ish vintage) Yazoo Kees ZTR with a Kohler CH25 V twin engine with a fixed timing ignition system, i.e., no SAM.
I bought it a while back from a mower repair guy outside Waco (I'm in Austin, about 100 miles away, saw it on side of road while driving back from Dallas, bought it on a lark). Repair guy had modified it with a push button starter after the ignition switch starter mode failed (though "on" position still works to power the harness), so wiring harness has been modified (the oil sentry oil pressure sensor on the breather has also apparently been disabled/bypassed as well but not the oil level sensor).
The tanks totally clogged up, but have since rebuilt the entire fuel delivery system. New tires all around as well. Replaced the main seal and rebuilt the breather (as I was thinking the main seal oil leak was caused by pressure blow from a broken breather reed). So I am vested in the ZTR now.
It's served me well for almost a year.
Cranked it up after sitting the winter to cut an acre property I have. It ran a bit warming up (with help from some starter fluid to get it going), then it suddenly stopped running, so checked the three things an ICE needs: compression, fuel, spark.
Compression and fuel are good, but spark appears inconsistent: weak to non-existent, both using a tester (automotive -- the HFT in-line spark type with a very faint orange light) and directly thru the grounded plug (sometimes a spark, sometimes not).
I want to replace the coils first and see if that is the issue, but apparently Kohler doesn't offer the simple single blade coils for the fixed ignition system on the CH25 anymore: instead, Kohler makes an ASAM/MD (something speed something module / magneto discharge?) retrofit kit (24-755-308-S) that includes new 2 blade coils, some new harness wiring and a new flywheel/magneto -- and is priced accordingly, i.e., expensive.
I am not too motivated to go retrokit and replace the flywheel (yet), so I would like to see if I can find some aftermarket coils that are compatible (even if they requires modification like rewiring or an additional resistor in-line) with the CH25 fixed ignition setup.
I've read about some aftermarket coils that work with some modification -- two specifically, one suggests adding a 4K ohm resistor in-line to get the coil resistance up-to-spec, and another suggests just disconnecting the kill ground wire to the coil altogether and just letting the carb fuel cutoff shut down the engine.
I'm looking for anyone who has the same system and has found some coils that will work -- even with some modification.
Thanks in advance for any help you might be able to provide me.
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