Starter not disengaging?

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GTXGreasemonkey

GTXGreasemonkey

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Long story sorry. Need the details. I have a 1972 Duster with a 360 LA block and a 727. I completely rewired the car using a painless universal Mopar wiring kit. As I got to a point I could ops check the engine starting system I bumped the ignition and it fired. I finished the complete car wiring and began putting the car together. I installed a brand new MSD mini starter. Went to start the car and heard grinding. Shut it off and duplicated the grinding two more times. After an inspection not turning much up I tried to start and only got a single click. Determined the new starter had a stuck solenoid now. Had another brand new MSD starter shipped and installed. Fired right up but still grinding. So I began checking wiring. I have a 00 battery wire going from the positive post on the batt to the large post of the starter. A 10 gauge wire going from the large post on the starter to the starter relay. Then a 10 gauge wire from the small post on the starter to the starter solenoid post on the relay. I have a yellow 10 gauge ignition wire straight from the steering column to the solenoid, and the neutral safety switch going to the other post on the relay. I’ve tested everything. The starter solenoid is getting 12.5v when the key is turned to run. The power goes away when the key springs back like it should. Battery power is solid. Tried two brand new batteries. The relay is getting power when the key is turned to run. When the power is off the starter gear is recessed back in the starter. Why is the starter not disengaging clean during operation? Is it a ground issue? Is it to much engagement? I know Mopar starters aren’t shimmed. I tried it with washers just to try, and it didn’t do anything. The mount seems aligned when installed. The front side of the flywheel teeth show the grinding evidence. I apologize for the length, and appreciate any guidance.
 
This is a new one to me on mopars. On most cars, this is caused by some binding or mis-alignment in the starter drive not allowing it to retract. Since you have replaced the starter two times I would suspect an issue with your bel housing or flywheel. Lets see what others think.
 
It sounds like your wiring path is wrong and you are powering the SOLENOID through the key switch RUN position, keeping the starter engaged.
12 volts from the key switch spring loaded START position should run through the neutral safety switch to the RELAY, and then to the solenoid which engages the starter.
The run position of the key switch should not have any power connection to the starter or solenoid.
 
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GTXGreasemonkey said:
I have a 00 battery wire going from the positive post on the batt to the large post of the starter. .
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Above sounds OK

GTXGreasemonkey said:
A 10 gauge wire going from the large post on the starter to the starter relay's LARGE POST .
Click to expand...
OK if that is what you did

GTXGreasemonkey said:
Then a 10 gauge wire from the small post on the starter to the SQUARE SCREW starter solenoid post on the relay. .
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GTXGreasemonkey said:
and the neutral safety switch going to the one of the flag push on post on the relay. I’ve tested everything. .
Click to expand...

OK if that is what you did

Remaining flag push on terminal should be "start" signal from the key

Quickest way to check this out is to get it "grinding" then quickly disconnect either of the small flag "push on" connectors on the relay. These should come from the "start" signal on the key and end up a the neutral switch. This should kill the relay and kill the starter OR IF IT DOESN'T

Prepare the next test in advance by getting tool ready or removing wire and connecting with a jumper that can be quickly disconnected. That is, this time disconnect the no10 coming off the 'square screw' of the relay which will confirm whether or not the relay contacts are sticking

MAKE CERTAIN that your IGN2 ignition bypass circuit is not interconnected with the start wire. THE ONLY connection on the start terminal of the ignition switch should be the starter relay. "Start" should NOT in any way be interconnected with ignition or coil

If none of these tests show anything good, I'd say its some problem down at the starter---dirt/ debri in the bell starter mount or some such
 
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If the sol is getting 12v in 'run' position [ as opposed to the 'start' position ], starter would engage as soon as you turned the key.
I have had grinding with MSD starters on GM cars. it is an alignment issue, most likely gear mesh is too tight.
 
Bewy said:
If the sol is getting 12v in 'run' position [ as opposed to the 'start' position ], starter would engage as soon as you turned the key.
I have had grinding with MSD starters on GM cars. it is an alignment issue, most likely gear mesh is too tight.
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How is this adjusted? I've cleaned the bellhousing and don't believe anything should be shimmed? I've tried two MSD Starters and one Speedmaster chinese starter. All have the same issue.
 
67Dart273 said:
Above sounds OK


OK if that is what you did





OK if that is what you did

Remaining flag push on terminal should be "start" signal from the key

Quickest way to check this out is to get it "grinding" then quickly disconnect either of the small flag "push on" connectors on the relay. These should come from the "start" signal on the key and end up a the neutral switch. This should kill the relay and kill the starter OR IF IT DOESN'T

Prepare the next test in advance by getting tool ready or removing wire and connecting with a jumper that can be quickly disconnected. That is, this time disconnect the no10 coming off the 'square screw' of the relay which will confirm whether or not the relay contacts are sticking

MAKE CERTAIN that your IGN2 ignition bypass circuit is not interconnected with the start wire. THE ONLY connection on the start terminal of the ignition switch should be the starter relay. "Start" should NOT in any way be interconnected with ignition or coil

If none of these tests show anything good, I'd say its some problem down at the starter---dirt/ debri in the bell starter mount or some such
Click to expand...

I'll take a look at this. Thank you
 
Murray said:
This is a new one to me on mopars. On most cars, this is caused by some binding or mis-alignment in the starter drive not allowing it to retract. Since you have replaced the starter two times I would suspect an issue with your bel housing or flywheel. Lets see what others think.
Click to expand...
I agree. I've removed and replace multiple starters dozens of times now. Is there any way to confirm this? As soon as power is disconnected i've watched the gear disengage immediately.
 
get under there with the inspection plate off and manually pry the pinion gear out to mesh with the ring gear. Does it go all the way out? Remove the small wire to the starter and check for voltage in start (good) and run (bad). Larger wire will always have power. These starters have a contact on the fork that moves the drive gear out to the ring gear. As soon as the solenoid is energized, the electomagnetic force pushes the fork out and makes this contact bridge the power connector to the motor. The contact is closed and the starter motor spins. The only switched voltage the starter needs is the relatively light solenoid load, that closes the contacts for the much higher amp draw starter motor. Hope this helps in diagnostics. check for lingering voltage at the solenoid after the ingnition switches back to run from start. Could be back feeding from somewhere. .
 
After further diagnostics there "IS" power remaining when the key springs back into the run position. I talked to Painless Wiring and they recommend a diode be installed in the circuit. We agreed the diode needs to be inline on the wire that runs between the Ignition post on the starter relay and the ballast resistor. We believe power is being back fed from the coil to the relay which powers to solenoid after the switch returns to the run position. I'm installing the diode tonight. We'll see?
 
sound theoretically possible......Hope thats the trouble. Someone here remarked about a few internet Mopar ECU diagrams that are wrong, with a possible back feeding issue.
 
GTXGreasemonkey said:
After further diagnostics there "IS" power remaining when the key springs back into the run position. I talked to Painless Wiring and they recommend a diode be installed in the circuit. We agreed the diode needs to be inline on the wire that runs between the Ignition post on the starter relay and the ballast resistor. We believe power is being back fed from the coil to the relay which powers to solenoid after the switch returns to the run position. I'm installing the diode tonight. We'll see?
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If power is coming from the coil IT IS NOT WIRED CORRECTLY and you don't need a diode
 
Installing the diode in the circuit corrected the problem. This isn't an exact match with the factory wiring schematic. Incorporating the Mopar orange box ignition and the ballast resistor created the back current issue. The red wire from the coil to the resistor meets with the wire coming from the starter relay ignition post wire. Once the motor started a small amount of current was flowing from the coil back to the relay preventing the starter solenoid from disengaging. A lesson learned. One can think it's not wired correct. As the car sits it's wired correct with what's installed. I appreciate the guidance and hope this helps someone in the future.
 
If you wire this correctly you don't need a diode. You do NOT tie the start terminal of the key to anything except the starter circuit. If you tie the IGN1 and IGN2 coming from the key switch together it will work fine.

This is where Painless NEEDS TO TAKE 5 ******* MINUTES and learn how Mopar starter/ ignition switches work
 
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