[AT] Well, I guess I didn't really want it to be easy

[Dean Vinson]

Or I'd have bought one that was all restored and perfect.

Decided to take a vacation day today just to work on the tractor, and it's
been a good day, if you define that as "getting to work on the tractor."
Short version is that the 1950 Farmall M is still in my back yard, still
won't start, and the problem now seems to be electrical:  no spark.   (It
had a spark last week when I tested it, and when it started yesterday, but
now I can't get anything.)

Tried to start it this morning to see if sitting overnight had fixed
anything, but no luck.  A couple of folks had suggested trying some ether,
but I didn't have any.  Tried some WD-40 into the air intake pipe on the
carb, but no luck there either.

Gasoline looks okay to me, although maybe it's bad or watery and I can't see
it.  Nothing noticeable in the sediment bowl, and when I open the drain plug
on the carb and let it run out and collect in a pan it looks fine.  Flow
rate seems fine.

I tested compression just to see what it was, and found that it's low in a
couple of cylinders:  115 psi in #1, 118 psi in #2, but only 90 psi in #3
and 105 in #4.  But that problem didn't suddenly pop up overnight and the
tractor started easily before, so it doesn't seem like low compression could
be the only problem.

(I guess 90 psi is low, since it's a lot lower than 115.  But does that mean
that 115 is okay?  What's a reasonable range?)

Walt had suggested that low compression might be making it easy to flood,
and the carb has been noticeably dripping gas after I choke it.  I don't
normally choke unless it doesn't start on the first few cranks, but it
hasn't been starting.  I took the air cleaner off so I could clean it and so
I could see the air intake pipe on the carb.  After cranking the engine with
the choke out (on), when I open the choke back up and stop cranking I can
see gasoline literally running out the air intake pipe.  It stops after a
few seconds, so I guess gasoline builds up against the inside of the choke
butterfly while cranking, and then just runs out when I open it up.  

Rick had thought maybe the float was stuck, so I took the carb off and
opened it up.  Float seems fine, but there was some watery brown crap in the
bowl, looked like the same mess I'd cleaned out of the air cleaner cup
yesterday.  (Cecil, looks like I owe you some shim stock).

Second thing I noticed was that the main adjusting screw wasn't even close
to the seat, like about ten turns backed away from it, just the very tip of
the needle sticking through the body of the carburetor.  It had evidently
been that way a long time, since there was so much gunk built up around it
that it wouldn't screw in any farther.  I had to take out the packing nut
and clean the gunk out of the hole in the carb body with a little
screwdriver.   I cleaned everything up as best I could and put it back
together, closed the main adjusting screw all the way then opened it back up
half a turn, and put it back on the tractor.  Cranked it over but still
nothing.  Tried opening the main screw another half turn, but that didn't
make any difference.  Same deal as before with gasoline accumulating behind
the choke when I close it, then running out the air intake when I stop and
open it back up.  Cranks over fine but not so much as a sputter.

By then Charlie had suggested putting a 12V battery in, which sounded like a
good idea.  Cranks like hell now, which I kind of like, but still doesn't
start.  I tried a few adjustments to the carb but nothing.  So okay, all
kinds of cranking power, air and gas, but not even a sputter?  Back to
electrical.  Went to look at the spark, just to see how they compared to the
ones I saw on Sunday when I'd first run into the no-start problem and still
had the 6V battery in.  Figured they'd be nice and big tonight with that 12V
battery, but I couldn't get any at all.  Tried three of the four plugs, and
nothing. 

Jumped a wire around the ignition switch, made sure polarity was correct at
the coil, and re-checked plug wire order and grounds (thanks, Farmer, Mike,
Jim, Lew, James... :-), but still nothing.

Rick has been patiently suggesting I replace the condenser, so that seems
like next on the list.  Only trouble is I can't figure out how to get the
distributor apart to get at it... as Jim had mentioned in a previous thread
I guess I've got an after-market distributor since it's one of those
90-degree vertical drive units.  If that little plastic disc under the rotor
lifts up out of there, I sure as heck couldn't see it.  I'll try again
tomorrow... it has to come off somehow.

Meanwhile, I've at least gotten some other stuff done on the tractor in
between all these attempts to start it.  New oil pressure and temperature
gauges, new engine oil and filter, and I gave the air cleaner its 50-year
cleaning.  I bet that breather tube from the cylinder head hasn't been open
in years.

So as it got dark I put the air cleaner back on and filled the cup with
clean oil, and at least had the satisfaction of a dirty but necessary job
completed.  Until... the damn cup started to leak from a pinhole in the
bottom.  I'd seen a little pit in the bottom of the cup when I was cleaning
it out, but didn't think it went through.  It does.  *@&#!!.

Dean Vinson
Dayton, Ohio
www.vinsonfarm.net