Starter solenoid won't kick in... Ignition test points?? I've got a 74'
Merc Montego that recently failed to turn over when the key was put into the
start position. The standard 'screwdriver' test, where the screwdriver is
used as a bridge between the positive side of the main relay lugs and the
field pole of the relay, works just fine. Car starts (with key in on
position). In the short term, I have adopted a 'starter switch' to crank
the engine. The wire going back to the firewall looks OK (no breaks), So I
suspect something either in the firewall or in the ignition circuit. Any
Sure it can. The screwdriver just proves there's power going across the
solonoid; not that the coil that operates the solenoid is working. You could
very well be right, but the solenoid can also be bad. It's also much easier to
work on than the switch.
Act, it does prove the solenoid works as the current from the battery is
applied to the 'field winding' then energizing the magnet that throws the
switch and kicks-in the starter. Also, the solenoid was replace (making the
engine compartment look nice and the old one looked like crap anyways. Same
result), The new unit also does not 'throw the switch'...
I know the 'key' moves a rod down the column to the actual 'Switch'. Is
this where we think my problem is?, and is it a matter of replacing this
unit (if it's available)? Wouldn't think that part would go bad... but
No, he activated the solenoid by applying 12v to the proper terminal of it.
If he used the screwdriver to jump the low gauge 12v wire on teh battery
side to the low gauge wire on the starter side then he would have bypassed
the solenoid. He simply took the ignition switch out of the equation.
As Neil mentioned, it could also be the neutral safety switch. I didn't
think of that. I bypassed mine in my '68. In '68 ford installed these
cheesy-assed neutral safety switches with plastic 'clip-on' part into the
column shift linkage and a cheesy casing and internals for the switch. I
tried replacing the whole thing and it worked twice then broke in the same
way the original broke. Very low quality, when compared to the high quality
part used the previous model year, but the collapsible steering column
necessitated a new type of neutral safety switch.
Anyway, it could be the wiring, the neutral safety switch, or the ignition
switch. I would first bypass the neutral safety switch, then check the
ignition switch with a multimeter to ensure it is making the connection when
in the 'start' position. If neither of those does it the problem must be
Ah, never thought about the neutral safety switch! That would be an easier
fix! This is a fixed column car (no tilt), but I will take a look at the
switch. Where should I be looking for it? What does it look like?
If you have a column shift it should be on the steering column down low near
where it goes through the firewall. If you have a floor shift it is probably
mounted on the side of the transmission or below the shifter. The column
mounted one should look like a little half-moon shaped thing wrapping around
maybe 1/4-1/3 of the column. It may also be a different type with a peg
sticking out into a linkage that you can see. It ought to be fairly obvious.
I'm not sure what the column shifted type looks like as I've only worked on
one column shifted car before and never needed to touch the transmission or
neutral safety switch. It should be connected somehow to the shift linkage
though and have wires coming out of it.
You can't just disconnect it, you need to 'jump' a connection between the
two wires that it connects when in neutral. On my '68 the plug has 4 wires
(neutral safety switch controls reverse lights too), so I didn't get the
right two wires the first time.
My Pinto is in the same boat, exactly. I have the cheap universal horn
button on the center console to jump the starter relay. My problem is only
intermittent, so I use the button when necessary. My neutral start safety
switch is ~$30, so I'll get around to replacing it sometime in the future...
Put a test light on the wire that energizes the relay and ground. Turn the key
to start. If the light laminates everything up to that point is ok. The relay is
grounded through the relay housing to the body. Are the fasteners tight and
clean? Use a ohm meter to test the primary circuit to ground. Again with the
test lamp, this time at the starter motor. Install the test lamp on the wire
from the relay to the starter. Turn the key to start, does the lamp light?
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