1970 Mach1 Ignition Problems?

I need some Help with a issue I have grtting my 351C to start? The problem is that when I turn the key to the start possition the Motor
turns and Dose Not Start? However, when the key goes to the on porrition the motor tries to start??? What's up with that? All I did was replace my old Mallory Unilite distributor with a New MSD ready to run distributor? The Motor was starting fine with the old distibutor. I made sure I installed the new MSD in the same possition as the Mallory, the rotor was pointing to the #1 plug wire and the #1 piston was @ TDC. I double checked all the wiring and all is good per the MSD instructions. SO, there should be No reason for the Motor Not to Start? HA! well I guess if I lived in a perfect world. This is a Real Pain in the Butt! Dose anybody have any idea's?
 
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The most probable answer here is that you may have either been off a tooth when you reinstalled the distributor, or you have a bad connection/ground with the new MSD install.
I doubt that your ignition switch decided to poop itself right after you changed the distributor, but it could have happened.
 
The most probable answer here is that you may have either been off a tooth when you reinstalled the distributor, or you have a bad connection/ground with the new MSD install.
I doubt that your ignition switch decided to poop itself right after you changed the distributor, but it could have happened.
Thanks for your reply Woodsnake. I checked the position of the distributor and with the #1 Cylinder @ TDC the rotor is pointing to the #1 Plug wire, so all is good there. I checked all the wiring for the MSD and all is good per the MSD instructions. So, at this point I have No Clue as to what the hell is wrong. Do you think it could be the ignition Switch? If so, than I'm screwed. Because there are No swithes available for a 1970. Any ideas?
 
Thats the lock cylinder, the switch on a 70 is mounted on the column. THe Echlin switch you get from the parts stores say they are for a 70, and will work fine, but you need to cut the plug off and splice on the plug from the old switch. There should be some old posts about this.
THe test you need to do has been posted-check for 12v at the coil in RUN and in START. It sounds like you have 12v in RUN but not in START.
 
Before buying anything! Just go back and double and triple check your wiring. I have an msd in one car and a mallory on the other. These 2 dist's hook up differently. Look back the the instructions for both dizzy's.
 
call MSD tech. you may need a diode installed in the power wire to the coil. it sounds like assuming you have it wired 100% correct that the voltage is backing up thru the coil power and going to the S terminal of the SR.
prob has something to to with the new dist elect ign. just my .002
 
Can't find that thread where I posted the pictures and info and part numbers, but here s a link to an article that shows the differences:
How-To: Replace '65-'73 Mustang Ignition Switches


Geeze, had to use Google to find it...

http://www.stangnet.com/mustang-forums/794654-ignition-wires-smoking-my-70-a.html
Thanks for the reply BarnStang. Thank you for the link, wow that's a lot of info. I'm glad I don't have the same problem. It's really a pain in the Butt that nobody makes a replacement 1970 Ignition switch. However, I did check out that Echlin Switch # ECHKS6583. They claim that it's for a 1970? However, like you said the plug is wrong. Anyway, back to my problem at hand. I replaced the Solenoid just in case and Nothing, I still have the same issue. I'll check to make sure that there is 12v @ the coil. I have checked all the wiring again and it All looks good. Damn! What am I missing? Maybe, I should put the old Unilite back in and see what happens? Do you think it may be the stupid ignition switch?
 
call MSD tech. you may need a diode installed in the power wire to the coil. it sounds like assuming you have it wired 100% correct that the voltage is backing up thru the coil power and going to the S terminal of the SR.
prob has something to to with the new dist elect ign. just my .002
Thanks for the reply Bluesman. Yes, I sent MSD Tech Support an e-mail
and this was there reply
Dear Sir:



Quite frankly, I have no answer for you. Have you tried tying the small red of the ignition and the small red of the ready to run distributor to the positive side of the battery? If not, try that. If the vehicle starts and runs you will have to remove the small red wire of the ignition in order for the vehicle to ‘turn off’.



It sounds as if the vehicle tries to start when the ignition is in the ‘run’ position so we know that the ignition will work, we just need to see why it won’t while ‘cranking’.



Thanks,

MSD Tech

Well, I'm not sure if this will work. Butt, what the heck I'll give it a shot.
 
Before buying anything! Just go back and double and triple check your wiring. I have an msd in one car and a mallory on the other. These 2 dist's hook up differently. Look back the the instructions for both dizzy's.
Hey jasonn, thanks for the reply. So, how different do they connect? Going by the instructions for each there almost the same? As far as I can tell the wiring in very similar. Maybe I'm missing something? I disconnected all the wires last night and reconnected them all again as per the MSD wiring instructions and Nothing, I have the same issue? This is Driving Me Crazy!
 
The MSD tech is trying to get to the same issue that has been mentioned twice already:

Check to make sure you have 12V ignition power to the distributor when the key is in the ON position and in the START position.

BarnStang:
THe test you need to do has been posted-check for 12v at the coil in RUN and in START. It sounds like you have 12v in RUN but not in START.
Yesterday 05:30 PM

It would be very simple to run a test wire from the battery positive to the distributor red wire. If it now starts normal and runs, you are in fact missing 12V in the crank position. The factory setup picks up the 12V during cranking from the I terminal on the solenoid. How your old Mallory did it, I do not know.

MSDDist.jpg
 
Well, I'm finally getting back to this issue. This did NOT work, the motor still did Not start and
all it did was Fry my Coil. My coil went up in Smoke? I think it's time to throw in the towel and
sell this bucket of bolts and get on with my life. This car has always been a pain in the Ass.
 
Most common problem when installing aftermarket ign is loss of power to coil in keyed start position.
When you run a wire to ign switch for bypassing the inline resistor wire you end up dropping off the lead from the starter sol I post. Now you have a cranks and won't start problem.

Simple test for this is remove brown wire from I post on sol, using jumper wire from I post to coil + side and turn key to start. If it fires off you need to trace the brown wire from sol to location it splices into the coil + feed in the harness and reattach it to your new coil+ lead for your set up.

Ps, where in SoCal are you located Fotoman?
 
Most common problem when installing aftermarket ign is loss of power to coil in keyed start position.
When you run a wire to ign switch for bypassing the inline resistor wire you end up dropping off the lead from the starter sol I post. Now you have a cranks and won't start problem.

Simple test for this is remove brown wire from I post on sol, using jumper wire from I post to coil + side and turn key to start. If it fires off you need to trace the brown wire from sol to location it splices into the coil + feed in the harness and reattach it to your new coil+ lead for your set up.

Ps, where in SoCal are you located Fotoman?
Thanks for the reply pabear89. Well, nothing seems to work. I don't understand this BS because the Mallory unilite that I replaced with the MSD Did Not have this issue? The Motor started just fine? Oh well, I guess I'll have to redo All the wiring again and see if that works? Hey, what kind of ignition system do you have on your 351C? I'm a Desert Rat, I live in the So Cal desert near Palm Springs.
Do you have any more idea's? Or should I just use her for Target practice?
 
I'm running a Mallory duel point mech adv.
Not into elect crap that drops off at will.
I installed a MSD streetfire box 2 months ago, got 20 mile on it and it took a dump. Yanked it out and it runs just fine with the old school point system.

:shrug: If your coil fried, it may have done in the dist pickup or box.
A complete test of system and wiring trace is only advice I can give at this time.

Ps. I live just to the west over the hill from you in Hemet.
Maybe we could get togeather and fix it sometime.:)
 
Like others have mentioned, I also think there is an electrical problem. Sounds like the coil/dist is getting power only when the key is in the Run position and not when in the start position.

This is easy to test. Disconnect the starter power cable. Have a helper hold the key in the "Start" position and check for power at the dist/coil with a voltmeter.

Or, run the test wire like shown in the diagram above.