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ThinAir |
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#1
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
My 73 has developed an issue. It will crank, but will not start. When the key is turned to the start position, all the lights on the gauges go out and the needles go to the bottom. It is my understanding from the "Dr. 914" tip book that this indicates a bad ignition switch.
I've checked the switch with an ohm meter just to try and educate myself on what is happening. I see that in the on or start positions I have continuity from pin 30 to pins X and 50, but no other pins. I know that I have power in the harness to pin 30 so that means that when I try to start it these same pins are getting power. I'm wondering if this is the way the switch is supposed to function, or what pins should I expect to get power. Assuming that the switch is functioning as it should, is there anything else (like a relay) that could cause this behavior? |
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Chris914n6 |
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#2
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Jackstands are my life. ![]() ![]() ![]() ![]() Group: Members Posts: 3,465 Joined: 14-March 03 From: Las Vegas, NV Member No.: 431 Region Association: Southwest Region ![]() |
The part of the lock cylinder that actually turns the switch gets worn. That would also cause the switch to not make solid contact on both pins at the same time.
<<< same problem (IMG:style_emoticons/default/smile.gif) |
Rand |
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#3
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Cross Member ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,411 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None ![]() |
Your ignition switch is not the problem.
Spark or fuel. |
Mark Henry |
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#4
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
(IMG:style_emoticons/default/agree.gif) with the majority of the time no spark.
You do have power to the coil right? I know stupid question but I have to ask.... |
ThinAir |
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#5
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
I don't have spark, but I figured that this was probably because of the problem with the ignition switch. I've also tried to start with no key cylinder involved - just used a screw driver with the naked ignition switch.
In trying to figure out why I don't have spark, I was wondering what connections the ignition switch should be making to pass power. The fuel pump runs so I believe that I have fuel, but I can't make out a separate sound that indicates that the injectors are "firing". My car was away since last November so I don't remember anymore what is "normal". Should the dash lights and gauges behave like that when I turn to the start position? |
ndfrigi |
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#6
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,965 Joined: 21-August 11 From: Orange County Member No.: 13,474 Region Association: Southern California ![]() ![]() |
contact point or pertronix? if pertronix, u might try replacing it or use contact point and try cranking it again. I have same issue before that it cranks so well but don't make it engine run. And make sure u have good new contact point, I did use a new contact point but it did'nt run and ended up fixing or checking several parts and at the end, I got a defective new contact point. Not because if is brand new, it will always be a working one.
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ThinAir |
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#7
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
This is Pertronix.
I checked the Pertronix with this procedure from http://itstillruns.com/do-test-pertronix-i...on-7993715.html "Unplug the red Ignitor module wire. Connect the red Ignitor module lead to the battery positive terminal using a jumper wire if required. Attach the black lead of the multimeter to the Ignitor module black wire. Attach the red lead of the multimeter to the battery positive terminal. Rotate the center magnetic sleeve of the distributor shaft by hand or by cranking the engine. The multimeter should show a fluctuation between battery voltage and zero volts. A constant voltage reading indicates a failed module or improperly installed Hall Effect shutter wheel." My test showed no activity on my volt meter. (In hindsight, I connected the VM to the black lead after removing the black lead from the coil. It's unclear if I should have left it connected to the coil.) I've replaced the Pertronix with an Ignitor II which was new in the box, but no change in the behavior. |
Mark Henry |
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#8
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
Last year I helped peted with his ignition he had two pertonix, IIRC an 1 and II, both had failed.
Installed points and it fired. |
ThinAir |
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#9
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
I hate points, but for diagnostic purposes I may have to resort to that.
For background - I had this car in the shop for some non-engine work. When it was done, they brought it to a car wash for hand washing. When they went to pick it up, it would not start. On the theory that something got wet in the engine compartment, they let it sit awhile, then tried again. It still would not start at first, but they wiggled the key around and it started. The shop felt it was clearly a bad ignition switch and we agreed that I would do my own repair. |
ThinAir |
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#10
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
It's ALIVE!
I tried again with the new ignition switch and noticed when I turned it off that there was the glow of a spark inside the switch, followed by a wisp of smoke (I thought only Lucas transmitted electricity via smoke). I changed back to my original ignition switch and tried again. No spark or smoke, and the dash lights stayed lit as well as the gauge needles not going to the bottom. Best of all - it started! I have a new switch coming. I'll wait until it arrives to put it all back together and drive it. (IMG:style_emoticons/default/driving.gif) |
cary |
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#11
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,900 Joined: 26-January 04 From: Sherwood Oregon Member No.: 1,608 Region Association: Pacific Northwest ![]() ![]() |
After the wisp of smoke I'd pull the stalk switches and check for short damage in the wires.. A couple of those wires run unfused from the battery.
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Mark Henry |
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#12
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that's what I do! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada ![]() |
I'd seriously consider my Ford solenoid mod to get the load off that switch.
All the aftermarket switches are crap, so you want to go easy on the original switch. http://www.914world.com/bbs2/index.php?sho...p;mode=threaded |
seanpaulmc |
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#13
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Member ![]() ![]() Group: Members Posts: 382 Joined: 6-December 16 From: Orlando, FL Member No.: 20,649 Region Association: South East States ![]() ![]() |
I'd seriously consider my Ford solenoid mod to get the load off that switch. All the aftermarket switches are crap, so you want to go easy on the original switch. http://www.914world.com/bbs2/index.php?sho...p;mode=threaded Is there a source for good ignition switches? I need one for my 73. Would appreciate the advice in advance of purchasing a poor product. Thanks |
ThinAir |
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#14
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Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,564 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
I'd seriously consider my Ford solenoid mod to get the load off that switch. All the aftermarket switches are crap, so you want to go easy on the original switch. http://www.914world.com/bbs2/index.php?sho...p;mode=threaded Is there a source for good ignition switches? I need one for my 73. Would appreciate the advice in advance of purchasing a poor product. Thanks I would check with PMB Performance. Switches aren't on their site, but I believe they can get them. |
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