Is There A Difference

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   Is there a difference between the 68/69 and a 70 wiring harness as far as the starting circuit is concerned?  I installed a 68/69 harness in my 70 (31 years ago).  Since that time I have had a hot start problem.  I have tried multiple starters, batteries and cables.  My father was a AMC mechanic for 45 years and even he could not figure it out.  I have a dura spark with a MSD ignition box.  It has a cutoff switch and even with the box off it still cranks hard.  HELP!!!!!!!!!!!!!!!!!!!!!!

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fast401 Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Sep/16/2008 Location: swanton, ohio Status: Offline Points: 3467	Post Options Post Reply Quote fast401 Report Post Thanks(0) Quote Reply Topic: Is There A Difference Posted: Apr/22/2010 at 1:30pm
	Is there a difference between the 68/69 and a 70 wiring harness as far as the starting circuit is concerned? I installed a 68/69 harness in my 70 (31 years ago). Since that time I have had a hot start problem. I have tried multiple starters, batteries and cables. My father was a AMC mechanic for 45 years and even he could not figure it out. I have a dura spark with a MSD ignition box. It has a cutoff switch and even with the box off it still cranks hard. HELP!!!!!!!!!!!!!!!!!!!!!!
	Disturbing the peace since 1970!!! AMX 19245 Facebook page - AMC Nation www.fast-401.4t.com

billd Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894	Post Options Post Reply Quote billd Report Post Thanks(0) Quote Reply Posted: Apr/22/2010 at 1:39pm
	Was the wiring the ONLY thing changed, or, was that ignition system changed then, too? Perhaps simply too much advance - but then you comment it's hard to crank even with the ignition shut down? The wiring is the same, however, even if it wasn't, it wouldn't change how it cranks. That's not controlled by the "wiring harness" but by the cranking circuit - battery, solenoid, cables and starter. The main difference between the two as far as starting and charging over the years is the different connector for the regulator in 69/70 vs 71 or 68. Now - if the alternator and regulator don't match, then you might not be fully charging the battery..... (see this link for more info) http://theamcforum.com/forum/alternator-and-regulator-id-and-connectors_topic13346.html
	http://theamcpages.com http://antique-engines.com

KermitDRambler Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/06/2007 Location: Cincinnati, OH Status: Offline Points: 2579	Post Options Post Reply Quote KermitDRambler Report Post Thanks(0) Quote Reply Posted: Apr/22/2010 at 2:41pm
	Is the engine block grounded to the chassis? If its there, is the wire good and clean and tight at both ends? Kermit had a similar problem and it was caused by that ground wire missing. Matt
	1967 American wagon http://www.mattsoldcars.com

billd Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894	Post Options Post Reply Quote billd Report Post Thanks(0) Quote Reply Posted: Apr/22/2010 at 2:52pm
	And you can't tell by looking, so even if it is there, remove and clean each end where it contacts the cross member and engine block. Ever see a throttle cable get hot? I saw a fellow fry the accel cable on a car because it was trying to ground back through the throttle cable when the block to frame ground was gone..... If that cable is missing or damaged, then it won't crank or charge well because of lack of ground path back from engine.
	http://theamcpages.com http://antique-engines.com

fast401 Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Sep/16/2008 Location: swanton, ohio Status: Offline Points: 3467	Post Options Post Reply Quote fast401 Report Post Thanks(0) Quote Reply Posted: Apr/23/2010 at 12:47pm
	billd/Kermit - The car has 3 grounds on it. One engine to chassis, one battery directly to the starter and one battery (825CCA deep cycle) to chassis in the trunk. Just installed a mini starter with the same results. This problem was their when it had points and it now has duraspark with MSD6 box and a Mallory coil. I thought there might be a difference in the wiring due to the location of the switches. Thought maybe something was missing in the wiring due to the column switch and the 68/69 wiring for the switch. Is the column supposed to be grounded to the firewall?
	Disturbing the peace since 1970!!! AMX 19245 Facebook page - AMC Nation www.fast-401.4t.com

poormansMACHINE Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Charter Member Joined: Jun/28/2007 Location: Shoemaker-Levy9 Status: Offline Points: 12302	Post Options Post Reply Quote poormansMACHINE Report Post Thanks(0) Quote Reply Posted: Apr/23/2010 at 3:52pm
	Hot start problem won't have anything to do with the steering column being grounded. What ga cables are you running? Check the voltage at the battery while cranking, then take the meter up front and check the voltage directly at the starter while cranking.