Ur,Ur,Ur, but no Vroom!
You say the car cranks but won't start.
1. Start by seeing if you have a spark. Take an spark plug and connect
it to one of the wires and wedge the threaded metal end of the plug
against a good ground. Be sure you can see the point gap. Have someone
crank the car over while you are watching the plug. You should see a
blue spark jump across the gap. If you don't have a spark, or the spark
is weak go on to section 3.
2. You must have a spark if you got here. Now its time to check wiring.
Remove the distributor cap and observe which way the rotor turns as
someone cranks the engine over. The service manual will provide both
the cap position of the number 1 spark plug wire and the firing order.
The number 1 cylinder is the front most cylinder of the engine, and they
are counted sequentially as you go to the rear of the engine. Start at
the number one wire position on the cap, an verify it is connected to
the number 1 spark plug. Going in the direction the rotor turns around
the cap, verify that the next wire is connected to the proper spark plug
and so forth until all connections are verified.
Now check the static timing. Verify that the engine is on the
compression stroke of cylinder 1. You can do this by placing your
finger over the spark plug hole and cranking the engine by hand until
you feel the pressure blow your finger off the hole. Line up the groove
in the vibration dampner (front crankshaft pulley) with the 10 degree
Before Top Dead Center line on the stationary timing mark. Connect your
test light from ground to the - coil terminal. Rotate your distributor
so the light just goes off and the rotor points to the number 1 wire
position of the cap.
In theory, your engine should now start unless you have a fuel problem.
3. No spark, or weak spark. Hook one end of the test light to ground.
Hook the other end to the + side of the coil. Turn the ignition on, the
light should light. It may not be very bright, as there may be a
ballast resistor. If you have no light, you are not getting 12 volts
from the ignition switch or the ignition relay on '77 - '80.
Remove the distributor cap. Verify that the rotor turns as the car is
cranked. If not, the distributor is not fulley seated or the gear(s)
are stripped.
3a.Now hook your test light up with one side connected to gound. The
other end should be connected to the - side of the coil. Turn the
ignition on, and as you turn the engine by hand you should see the light
flash as the points open and close. If it does not go off, the points
never close or you have a bad ground (go to 4). If the light does not
go on, the points never open or you are not getting power to the coil
(go to 5).
3b. Well the light flashes. The next step is to recheck your point gap.
Make sure that the follower block on the points is on one of the high
spots of the distributor cam before you adjust the point gap. Now
recheck for spark with your test spark plug, if you have spark, start
you engine.
3c. If you do not have spark, connect a spark plug wire from the coil
to your test spark plug. Crank the engine and see if there is spark, if
not it is most likely the coil or the one spark plug wire you are using
is bad. If you have spark the problem is most likely either a wire or
the connection through the distributor cap / rotor.
Take the distributor cap off again and visually check it for arcing.
Also try to determine if you are making a connection between the center
tower and the edge towers through the rotor.
4. The light did not go off in step 3a. Connect a short peice of wire
from the - coil wire (leaving your test light still connected to the -
coil terminal). Connect the other end of this wire to a good ground (do
not touch any of the bare wire or terminals as you will get a shock) and
the light will go out (sanity check). Now take that wire and touch it
to the base plate of the points, the light should go out. If it does, go
to 4b.
4a. If the light did not go out in step 4, touch the wire to the case of
the distributor. If it now goes out, there is a flex wire that connects
the point base plate to the distributor that may be broken. If it
doesn't go out, the case of the distributor is not grounded, look for
dirt between it and the engine.
4b. Verify that the points are closed by visual inspection whiling
cranking the engine by hand. Touch the wire from step 4 to each side of
the points. It should go out when either side of the points is touched.
If it only goes out on one side, either the points are dirty or are not
making contact. If the light goes out when either side is touched, then
the wire from the points to the coil is open.
Note: The wire from the condenser to the coil can break if extra wire
was not left to allow the base plate to rotate for vacumn advance.
5. The light never went on in step 3a. If the light doesn't light,
disconnect the wire to the points and condenser. If the light lights,
then the condenser or the wire may be shorted to ground. Replace it.
If the light still doesn't light, and it does light when connected to
the + terminal, then the coil is bad. Replace it.
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