Run Away Starter in 390

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Recently I have a starter situation with my 1968 AMC that has me rather confused....
Before I give the symptom, here is some background...

Car has started flawlessly for 2 years....  never had this problem before
RobbMc mini starter installed 1.5 years ago.
Reproduction AMC Battery installed 3 months ago, usually attached to Battery Tender when at rest
Wires to solinoid (all battery cables are new (1.5 years ago) and 0 gauge (THICK).
Connections at starter are good, clean.
Solinoid on starter is wired to the right post of starter solinoid per RobbMc instructions

Symptom:

At a recent cruise after the car sat for perhaps 1.5 hours I started up the engine.
Heard a kind of whizzing noise that I have never heard before for about 5 seconds then
it went away.
Upon garaging the AMX at home I checked the engine bay thinking perhaps the fan was loose or touching something... not the case.

One day passes...

Last evening upon starting the car the starter keeps going and going even when the key in the starter ignition is released.

I quickly disconnected the positive battery cable from the battery (Love those quick disconnects).

Then reattached the positive cable... the starter was at rest and not trying to start.
Humm I think what is this...?

I then figured this was a solinoid problem and having a spare removed the old one and
replaced it with the new one.

Tried starting again and yet again the starter just keeps going and going and going even when the key is turned away from start.

Your thoughts, comments and suggestions and trouble shooting tips are welcome.

Possible Culprits are:

Low Battery Amperage Condition ?
Ignition Switch is faulty ?
Both my solinoids (original and backup) are snafu and it is a Solinoid problem?
Wire problem from solinoid to starter?

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12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Topic: Run Away Starter in 390 Posted: Jul/09/2008 at 7:43am
	Recently I have a starter situation with my 1968 AMC that has me rather confused.... Before I give the symptom, here is some background... Car has started flawlessly for 2 years.... never had this problem before RobbMc mini starter installed 1.5 years ago. Reproduction AMC Battery installed 3 months ago, usually attached to Battery Tender when at rest Wires to solinoid (all battery cables are new (1.5 years ago) and 0 gauge (THICK). Connections at starter are good, clean. Solinoid on starter is wired to the right post of starter solinoid per RobbMc instructions Symptom: At a recent cruise after the car sat for perhaps 1.5 hours I started up the engine. Heard a kind of whizzing noise that I have never heard before for about 5 seconds then it went away. Upon garaging the AMX at home I checked the engine bay thinking perhaps the fan was loose or touching something... not the case. One day passes... Last evening upon starting the car the starter keeps going and going even when the key in the starter ignition is released. I quickly disconnected the positive battery cable from the battery (Love those quick disconnects). Then reattached the positive cable... the starter was at rest and not trying to start. Humm I think what is this...? I then figured this was a solinoid problem and having a spare removed the old one and replaced it with the new one. Tried starting again and yet again the starter just keeps going and going and going even when the key is turned away from start. Your thoughts, comments and suggestions and trouble shooting tips are welcome. Possible Culprits are: Low Battery Amperage Condition ? Ignition Switch is faulty ? Both my solinoids (original and backup) are snafu and it is a Solinoid problem? Wire problem from solinoid to starter?
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60

raysinvegas Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/01/2007 Location: Las Vegas NV Status: Offline Points: 2501	Post Options Post Reply Quote raysinvegas Report Post Thanks(0) Quote Reply Posted: Jul/09/2008 at 10:50am
	My money is on the ignition switch.
	Andy Ray 64 440H 64 440 Convertible 68 Javelin SST 343 69 Javelin SST 343 69 SC/Rambler

12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Posted: Jul/09/2008 at 11:51am
	Ok some more data after fiddlin' around with it.... Got a BRAND NEW Standard Starting solinoid (SS581) Attached it all up nice. Attached the battery. Tried starting with the key switch in the dash. Starter keeps running and running. Pulled the Positive cable off the post. Starter Stops. Reattached the positive cable... it does not continue to start. So... I attached my remote starter switch... one lead to the S post on the solinoid. Second lead to the + of the battery. (this test would eliminate the starter switch on the dash from the equation) No key in dash starter switch. Pushed the plunger on the remote starter... Starter jumps to life and keeps on running even after I disengage the plunger. So I call Robb at RobbMC He was very helpful and very understanding. After an explaination he felt it was the solinoid on the RobbMC mini starter that is to blame. It is getting stuck in the ON or engaged position. So he is sending me a new mini starter solinoid. This is a Caddilac Northstar Solinoid for th 1995 460 Northstar engine. It should be easy to replace once It gets here. Meantime I will pull the starter and check it all out. Stay Tuned.... To the Case of the Run Away Starter!
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60

bigbad69 Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jul/02/2007 Location: Ottawa, Ont. Status: Offline Points: 6686	Post Options Post Reply Quote bigbad69 Report Post Thanks(0) Quote Reply Posted: Jul/09/2008 at 12:31pm
	I had similar symptoms on a daily driver one time. Replacing the starter solved the problem. I didn't investigate whether it was the solonoid or motor itself (GM unit with attached solonoid). It sounds to me like RobbMC has you on the right track.
	69 Javelin SST BBO 390 T10

purple72Gremlin Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Charter Member Joined: Jul/01/2007 Location: Illinois Status: Offline Points: 16614	Post Options Post Reply Quote purple72Gremlin Report Post Thanks(0) Quote Reply Posted: Jul/09/2008 at 6:16pm
	solenoid on starter is my opinion.......

12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Posted: Jul/09/2008 at 6:34pm
	Pulled the RobbMC starter and the wires. Brought the wires to a local custom cable shop and they are making me a new 0 cable for the run to the switch solinoid to the starter. The bendix drive gear on the starter is NOT all buggered up so that is good. I may have the new starter solinoid from RobbMC by Friday. In the meantime I can begin to rip the solinoid out of the starter. In the meantime I did find an orginal and good working 1968 AMX/Javelin ingition switch with keys and bezel. These are NOT easy to find in working shape anymore. I will keep it as a spare. Edited by 12Gauge - Jul/09/2008 at 6:44pm
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60

bigbad69 Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jul/02/2007 Location: Ottawa, Ont. Status: Offline Points: 6686	Post Options Post Reply Quote bigbad69 Report Post Thanks(0) Quote Reply Posted: Jul/10/2008 at 11:27am
	I would tend not to think it is the ignition switch because cutting the battery and reconnecting it de-energises the starter. If the switch was bad, I would expect the starter to turn as soon as the battery is reconnected. However, it doesn't hurt to have a spare ignition switch. I have also seen solinoids self magnetise. i.e. they don't release when the key turned from start to run. This happened a couple of times on my brother's Ford 390. The battery was low, and car hadn't run for a while. Cranking speed was slow and the starter held on for 15 seconds or more. I'm guessing the high current draw built up excessive magnetic flux in the solinoid. The only way to stop the starter from turning was to disconnect the battery. On reconnection everthing was fine. This only happened after holding the key on start for excessively long periods of time. 12Gauge, since the RobMC starter has a built in solinoid, and the factory one is mounted on the inner fender, do you have one of them bypassed? You only need one in the circuit, so either bypass the one on the starter, or run the start wire down to the starter and bypass the solinoid on the fender.
	69 Javelin SST BBO 390 T10

12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Posted: Jul/10/2008 at 1:10pm
	BigBad: The RobbMC mini starter uses a solinoid built into the starter to PUSH the bendix drive into the flywheel. The fenderwall solinoid (Ford Style) for the low voltage to high voltage transition is for the ignition switch starter purposes. This is really more like a relay in my humble opinion with low amperage on one side and high amperage on the other. Both are needed you cannot as far as I know, get rid of one of them, you need both.
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60

12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Posted: Jul/10/2008 at 4:16pm
	Bench tested the RobbMC starter and solinoid on the starter. Yup... I can duplicate the problem with the bench test with power to the starter and the solinoid the starter runs and extends the bendix drive. However when the bendix drive power is removed the starter keeps running and the bendix drive stays extended and it should not. So the solinoid is the culprit here. I removed it and there is a tell-tale odor of burnt varnish coming from the solinoid so there was/is a problem-o with it. The new one should arrive tomorrow or Saturday. The install seems simple enough. You do need a torqz type socket which luckily I have to remove the three screws. And a #13 metric wrench for the connection. Otherwise it is easy. The solinoid is a real nice piece of gear... probably not inexpensive to manufacture.
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60

12Gauge Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/08/2007 Location: Connecticut Status: Offline Points: 174	Post Options Post Reply Quote 12Gauge Report Post Thanks(0) Quote Reply Posted: Jul/11/2008 at 10:18am
	The RobbMC solinoid arrived today. Installed it in the starter. Replaced all the power cables to the starter... Viola! She's 'a works! Thanks to all for your thoughts and support. Thanks to RobbMC for getting that Solinoid out to me and for great after purchase support! A great vendor and one we all should support IMHO. And lastly, some new knowledge gained and tucked away for future reference. It is always nice to trouble shoot and repair a problem on the AMX yourself. Hopefully this thread may be of help to those in need some day!? Cheers! Edited by 12Gauge - Jul/11/2008 at 10:21am
	Art In Connecticut Nothing Lasts Forever... If you give it enough TIME 1968 AMX 390 4-Speed 1991 ERA Cobra Replica - 428 & Toploader 2016 Tesla P90D with Ludicrous Mode 2011 Volvo XC60