This one is pretty easy. Your points are probably corroded. But here is
the whole procedure..
1. Check for voltage at the hot side of the coil with the key on. You
should have battery voltage.
2. Check for voltage at the arm on the points with the key on. With the
points open, you should have battery voltage.
3. Take one plug and plug wire off. Hook them up to the high voltage port
on the coil. Ground the spark plug (laying it on the valve cover usually
works.) Unhook the low voltage wire between the coil and distributor.
Take a jumper and short out the wire between the coil and the points.
Every time you touch ground with the jumper, you should see a spark at the
plug. If you don't, the problem is somewhere in the coil.
4. Remove the jumper, hook up the low voltage wire from the coil to the
distributor, and roll the engine over. You should see sparks at the test
plug. If not, the points are probably corroded or the condenser is shot.
Replace both and adjust the points to the proper gap. Try it again. If
you don't see a spark this time, check the wires and screw terminal in the
distributor for worn insulation that is shorting to the distributor.
5. Put the high voltage wire back between the coil and distributor and
hook the test plug wire up to the open terminal on the distributor. Roll
the engine over. I would now almost guarantee that you will get a spark
now. If you don't, it's time for new plug wires, distributor cap, and
rotor. Also check that the wires are hooked up to the correct spark plugs.
6. At the risk of starting a Champion vs AC plug war, I will state that
old Champions seem to be much more prone to internal shorts that bleed off
the spark. Put in the correct plugs with the proper gap.
7. If it still doesn't start, and you are getting gas, check that when the
valves are closed and the piston is at top dead center of No. 1 cylinder,
the rotor in the distributor is pointing very close to the terminal for the
no. 1 plug. If not, rotate the distributor or redo the plug wires on the
cap so that it does. This is close enough on timing for the engine to
start and run. Finnesse can come later.
8. If this doesn't work, try a squirt or two of gas down the carburator
throat.
If you have compression, gas, and spark at the same time in the same
cylnder, it almost has to run. Nothing Chevy designed has any mysteries to
it about this.
Among the tools you need are a voltmeter or test light, a spark plug
wrench, a screwdriver, and feeler guages for the plugs and points.
Go to it!
Bruce Kettunen
57 3200
Mt. Iron, MN
>Finally some progress on the truck. Here's the latest hang up. We finally
>worked enough to get the starter to crank over the engine, and that is where
>we sit right now. The motor spins, but no spark. Any ideas where to start?
>How would a person check through the ignition system to determine if
>anything is either bad or just not hooked up properly? And what can someone
>do with just a multimeter and a screw driver to begin with? I am not afraid
>of hard work, but I prefer to start with the simple stuff and work out
>toward the more difficult possibilities.
>
>Any hints and/or steps (simple or detailed, detail preferred) would be
>warmly welcomed, as it finally begins to seem like winter in Minnesota (a
>light dusting of snow has tried to fall).
>
>Thanks again for the many great assistances in the past. You have all been
>very helpful.
>
>Mike Anderson
>1948 Thriftmaster 3804
>http://www.visi.com/~m1a20/Truck (someday the site will have a new look to
>it, not yet though)
>
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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