On Tue, 02 Aug 2005 15:12:21 -0500, Scott Willing
[blah blah blah two coil failures on old Case garden tractor with 14hp
Kohler K321, starter/generator, voltage regulator, points etc.]
I sincerely appreciate your efforts to help.
Although my regular guy (he'd cringe at that) at Kohler was off this
week, another fellow at Kohler got back to me in a day or two.
Here's the 411, direct from the horse's mouth:
"No, this coil does not have an internal ballast resistor. The
ignition coil/system on this engine is not designed for a ballast
resistor. As you know, automotive coils are usually used with a
ballast resistor-however, not this Kohler system."
To help me determine if the coil I had was correct (since at that
point I thought there might be coils with, and without, a ballast
resistor) I also asked what the coil windings should measure,
DC-resistance wise. He said:
"4-8 ohms across the primary terminals 8,000-12,000 ohms from the
high tension tower to either of the primary terminals"
Then he went on to caution that a mere DC resistance measurement
doesn't prove that the coil is good; for that you need to have it in
service or on a tester. I agree, but it's nice to know when the
measurement you make indicates that the coil is bad for sure.
So... I put the thing all back together and once again it's running
like a dream.
This time I stuck a meter on the charging system. It freaked out -- a
cheap digital meter I use for "unfriendly environments" which was
apparently picking up RF interference, reading wild random numbers on
any range whether or not the leads were connected to anything. Good
I fished out a good old-fashioned analog meter, and using that I
measured 14V steady as a rock throughout the operating range. I was
quite impressed frankly; I expected more of a stepped response. Helps
that the battery is in good shape I suppose.
I'd love to analyse in detail how this particular voltage regulator
works. Replacements are still available but as an electronics guy I'd
be tempted to build myself a bullet-proof solid-state replacement.
It remains a mystery why I suffered two coil failures. I'm thinking of
mounting a couple of gauges on this thing - even gaff-taping my old
analog meter to it temporarily - to keep an eye out for some kind of
intermittent problem. If I lose another coil -- well, let's just say
it's a good thing I don't have any hair left to pull out.
BTW, I've been getting parts and manuals for my old Case from:
http://store.casegardentractors.com (that's >>tractorS<<, same URL
with a singular tractor is something else.)
This site is a treasure trove operated by an old enthusiast owner.
Unlike a lot of sites that turn up when googling for Kohler or Case
parts, this one has most everything they sell individually pictured on
the site with prices for each. And - of special note for Canadians -
the guy does not charge a fortune to ship into Canada, will ship by
regular mail (a must for my rural PO box) and his prices are better to
start with, even after exchange and shipping. Probably due to low
overhead. (E.g. US$38 for a set of three mower deck blades vs CDN$29
per blade from the local dealer???)
Anyhow, enough of a plug for the site, I'll be sorry when everyone
goes there and buys up the parts I need. :-)
One of the items in the catalogue is a wiring harness. I noticed in
the photo that there is an inline fuse-holder, which I found
interesting as my machine has no fuses or other protection. I know
where I'd want to put a fuse, and interestingly there's a wire splice
on my machine in that exact location -- ahemm. One of the manuals
that's on its way to me in the mail site should tell me for sure.
As long as I'm plugging stuff, permit me to observe that Kohler really
seems to be one of those rare great American companies (this from a
Canuck no less!) that one associates with mostly bygone times. Kudos
to Kohler for friendly, timely and detailed support.
And thanks again to all those folks who joined the thread. My first
experience of this newsgroup has been overwhelmingly positive (at