1974 C3 4 speed won’t start
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1974 C3 4 speed won’t start
I have a 74 roadster 4 speed. Not getting power to the inside terminal on starter solenoid, purple wire I think, when I move to start position. Verified starter works when I jump the solenoid with a screwdriver. Outside solenoid terminal gets 12 volts when key is in run position. Battery is good. Wipers and other accessories energize with ignition switch. Moving to start position does nothing. Any tips?
Melting Slicks
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Check your grounds. Specifically the negative battery cable grounding to the frame on the bottom of the car near the battery box. Remove the bolt and clean the frame to ensure you’re connecting to good metal.
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Power goes from ign. switch to clutch safely switch through safely switch when clutch is fully depressed. Then one more connector on the firewall, just right of center. Then down to starter. Follow the wire.
Le Mans Master
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pbennett,
Always a good possibility that the solenoid is toast.
The starter itself will outlive 2 -3 solenoids.
Poor solenoids have to do all the work. Take current in, send current out, engage the Bendix / spin the starter.
All this, in extreme heat of the exhaust pipe. Worse with headers. Do you have a heat shield in place?
If you do end up replacing the solenoid, look for a brown end-cap. That is heavy duty and ceramic to handle the heat.
Always a good possibility that the solenoid is toast.
The starter itself will outlive 2 -3 solenoids.
Poor solenoids have to do all the work. Take current in, send current out, engage the Bendix / spin the starter.
All this, in extreme heat of the exhaust pipe. Worse with headers. Do you have a heat shield in place?
If you do end up replacing the solenoid, look for a brown end-cap. That is heavy duty and ceramic to handle the heat.
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Well I’ve checked the grounding to the frame,, confirmed the clutch safety switch, changed out the starter solenoid and still won’t start. Something clicks on the fire wall when I rotated the ignition switch but no power is transferring to the hot side of the solenoid. Any thoughts on what else to check?
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From: mount holly NC
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Do you have this on your firewall?
Remove the silver relay and by-pass like this:
This is the same as splicing the light green /black to the purple.
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pbennett
Since it does turn over when you jump the solenoid with a screwdriver I would try bypassing the neutral safety/clutch interlock switch..... just in case it just quit working. Easy and quick so worth checking.
Normally on a "click" I would say clean your battery posts and ensure they're tight but you said it turns over with a screwdriver???
Since it does turn over when you jump the solenoid with a screwdriver I would try bypassing the neutral safety/clutch interlock switch..... just in case it just quit working. Easy and quick so worth checking.
Normally on a "click" I would say clean your battery posts and ensure they're tight but you said it turns over with a screwdriver???
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Correct, starts when I put the ignition in the run position and jump the solenoid with a screwdriver. Solenoid isn’t getting power through the momentary position of the ignition switch. Tried bypassing the clutch safety switch and starter interrupt relay. Maybe ignition switch in the column?
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Looking for any help here. On the clutch safety switch there are two wires - purple and purple with a white tracer. I assume one of those is supposed to have 12 volts on the feed side to the switch… both are zero. I believe that feed (purple I think) comes from the ignition switch…. Which I just replaced. So what feeds the momentary start circuit on the ignition switch? What color wire and where does the feed come from?
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Red, from power distribution. Which I do not have a schematic for but I believe that is on the horn relay on a 74.
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2 Red wires coming into the ignition switch. From power distribution. Do you have power on both of these? Then see purple/ white wire to clutch safely switch.
The rest of the start circuit.
Best of luck.
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Thanks 4-vettes - that diagram was helpful. Turns out the purple wire out of the clutch safety switch is fried and doesn’t have continuity out to the starter interrupt relay in the engine compartment. I ran power to the purple wire and it also turns out the out from the relay - brown I think - doesn’t have continuity to the starter solenoid. So basically looks like both wires are fried.
Anyone know if they put fusable links in those wires?
Simplest solution seems to be to run a new wire off the clutch safety switch straight to the starter solenoid. I patched that together just to try it and it works.
Any big issue bypassing the starter interrupt relay in the engine compartment?
Anyone know if they put fusable links in those wires?
Simplest solution seems to be to run a new wire off the clutch safety switch straight to the starter solenoid. I patched that together just to try it and it works.
Any big issue bypassing the starter interrupt relay in the engine compartment?
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I would DEFINITELY bypass the starter interrupt. No, there were not fusible links in those wires.
yes, simplest way would be to run new wires from clutch switch to solenoid.
get wiring Mate, this has been broken for 2 long now!
yes, simplest way would be to run new wires from clutch switch to solenoid.
get wiring Mate, this has been broken for 2 long now!
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Glad to hear you finally got it going! 