Welcome to the... Message Board for Plymouth Roadunner Owners & Enthusiasts (including Superbirds and GTX) Fellow B-Body Satellite and Charger and F-Body owners also welcome
rrroger New Beeper
Posts: 1
(12/25/01 3:10 pm) Reply
70 RR Ignition Switch
G'Day fellow road chicken lovers. FNG here and excited to find a site for us unappreciated bastions of true purpose built performance. Unlike a lot of the muscle cars of our era, Plymouth was up front with the design and purpose of the Road Runner. Nutt'in Fancy, just brute strength!
Anyway, I have a 70 RR w/ Column mounted ignition switch. I can crank on it all day with no fire. If I let off the key and the switch returns to "ON", it will fire and start (if I hold my tongue just right). I have been investigating this for a while. If I use a remote starter on the under hood relay, key ON, a couple of pumps on the linkage and it comes to life quite readily!
What connectors can a point to point to isolate the exact cause before I start tearing into the steering column?
BTW, RR340, where do I send a buck to keep this board alive?
well the wiring is ok if you can start it under the hood like that. Sounds like your key switch is just worn out(no doubt from use, which is a good thing as it means this car is driven a lot) You may be able to rebuild the switch but i think a new one can be had for 40 bucks or less.
Re: 70 RR Ignition Switch
When the ignition switch is turned to START, the normal ignition circuit IGN 1 is shut off and the IGN 2 circuit bypasses the ballast resistor and supplies power to the coil. When the IGN 2 circuit fails, there will be no power to the coil when cranking but it will be restored when the switch is returned to ON.
The IGN 2 circuit is the brown wire on one side of the ballast. Check this wire for power when cranking. Also check this wire at the firewall disconnect and the ignition switch connector under the dash near the column. If there is no power at any of these connections when cranking, the switch is bad.
'98 Ram 1500 Quad Cab Sport
'68 Hemi RR 4-speed
'62 Dart Max Wedge
Re: 70 RR Ignition Switch
ok just looked in the service book I have for '70 model Challengers and Darts. Not sure but pretty certain it applies for b-bodies. Basically I think you will need one as there are about 15 steps to removing the switch. You have to take off the steering wheel and go at it from the way! I'm glad my '69 has it on the dash where it is easy to get to. I'll have to ask my mechanic friends if there is a easier way.
rrroger New Beeper
Posts: 2
(12/26/01 8:55 am) Reply
Re: 70 RR Ignition Switch
Thanks for the info, I will try the Ignition #2 measurement first. I will have to face the music and start tearing into the column. My service manual indicates the several steps needed to get to it as well, I was trying to avoid it!!!!
Re: 70 RR Ignition Switch
Let us know how it turns out. I may have to tear into my Challengers' column one day, it would be nice to know if it is as rough as the book makes it.
"69 Road Runner 383 going to 440, 6brl hood, likely gonna race it
'70 Challenger R/T clone 440, 2nd owner, 300,00 miles on body, not kidding
'92 Cummins 1 ton, in need of restoration bad
'79 1 ton-for sale
'01 WS6 T/A- for sale
Re: 70 RR Ignition Switch
I just put an ignition switch in my 70 RR a few months ago. There is a lock plate under the steering wheel that I could not figure out how to remove(it was pressed on and then peened in four places to hold it) I ended up taking the steering knuckle apart and sliding the shaft out just enough to get the switch out. Put it all back together and works great now.
Re: 70 RR Ignition Switch
Kinda continued from the original post;
A while back I posted a question as to why the bird would not fire until the key came back to the "On" position. I received a lot of very good input as I was trying to avoid tearing into the steering column. I have replaced the ballast resistor and watched the volt meter fall to Zero on IGN #1 when I turn the key to start. It starts fine when I use the remote starter on the relay.
Yesterday, I applied pressure to each of the three connectors on the fire wall, and did the same thing from inside. Checked the clutch switch, everything OK there. Tried the key "BAM" Fired right up!
Today, started fine in the shop. I go to the store, tried to start it, just cranked, pulled out the trusty remote and it started.
It's the original harness routed correctly (completely disasembled dash during resto), it has started fine for a couple years. What can I do to better secure the connectors?
Re: 70 RR Ignition Switch
HHHHUUUURRRRRAAAAAYYYY!!!!!! Cleaned the males and the females of the bulk head connector specifically "M" and I think "Q". It fired from the key!! Thanx for everyones input.
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