Brake light switch???

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BadBee

BadBee

'69 Dart 440/6/4 speed
Joined
Aug 16, 2015
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Hello All,
My BLS is the snap in kind, it works fine(when it wants to) so the Brake lights stay on unless SOMETIMES I reach down and pull switch in line with pedal,(I know everybody's saying
Bracket outta line etc) Fact seems brake pedal has at LEAST 1/2 " slop returning to the top!
Resulting in my switch not working properly, I went and bought an adjustable switch and still a bit of SLOP! Brakes are manual drums rear discs front 69 Dart, is MC bad? Rod ? Brakes work fine.main issue seems pedal not returning to top to depress switch!! ???
Thanks
Mitch
 
The pedal connects to the rod, which connects to the master cylinder and is held in place there

I would check to see if the rod came loose
 
The only return spring is in the master cylinder. maybe that spring has weakened but... In those cases where the master doesn't fully return due to too long pedal rod, residual pressure will drag the brakes.
Having seen a firewall flex issue in nearly new Ford trucks ( at the clutch master and preventing that pedal activated starter switch operation ) I can suggest a theoretical fault. Yes the return force in that little clutch master was quite a bit stronger. Those trucks were nearly new though. Your firewall is 50 years old. Has it slowly flexed, moved the master away from the pedal? Murphys Law says what can happen will happen.
So if I was certain the pedal to master rod was OEM correct and the correct master cylinder was in use ( different/wrong master cylinder could have a thicker mounting flange, not 1/2 inch thicker though... hummmm, scratch that ), first I would check the pedals upper pivot point. Should find a bronze bushing there. I don't know what fault condition would be caused by significant wear there ( probably same ). I know due to geometry a little change at one end is multiplied at the other end.
If I ruled out everything else leaving the only other fault to be firewall movement I would buy the adjustable pedal to master connecting rod from the aftermarket. That solution is a heck of a lot simpler than the reinforcement plate Ford had us install in large number of their trucks.
 
Hello Redfish,
Fire wall is SOLID! I'm guessing MC is probably gone there is only 58K original miles and car is Original for the most part less the 440 it was a 340/4 speed, I'll investigate and post more findings
thank you
Mitch
 
I had a similar problem. I installed an adjustable push rod from a vendor advertising here (Can.t remember who). It had a rather large heim joint on the pedal end and came with two washers that I presume were meant to straddle the joint. Upon installation, I noticed the rod didn't appear to enter the master cylinder squarely so decided to omit one of the washers. What I didn't notice was the chubby heim joint then rubbed on the side of the brake pedal. The pedal never seemed to return to the same place making adjustment of the stop light switch impossible. I was always using my toe to pull the pedal 'up'. I finally removed the brake pedal and found where the heim joint was rubbing. A little grinding on the pedal and heim joint fixed the problem.
 
Thanks Logan I'll check in to that when I get to it after Carlisle and keep us all Posted!
Thanks,
Mitch
 
The pedal rod to master is a ball socket mating, like a ball joint, because that line changes up/down slightly as the pedal moves. Thus the left/right line doesn't have to be exactly square either. As we push the pedal sideways wearing away the right corner of the pad, the upper bushing wears changing that rod line even more. Doesn't effect anything except for brake lamp switch alignment. We didn't get a left/right adjustment in that.
 
I had a 69 Dart and the brake light switch bracket was adjustable. When you say your original is "snap-in type", that is what I remember. It is a round plastic tube which snaps into the bracket. You don't adjust that. What you do adjust is where the bracket bolts to the pedal bracket. There is a slotted hole. Crawl under and look again. Loosen the bolt on the bracket and slide it towards the pedal.

Unlike new cars, the whole switch is exposed and easy to see how it works. Almost the same as your door jamb light switches, except those short to gnd and the brake-switch switches the hot side.
 
A lot of people don't realize that there were two completely different brake light switches used on these cars.
The standard one is a small switch mounted on an adjustable bracket. This one can be identified by its spades coming off at right angles to eachother.
The other is the heavy duty "trailer towing" type. This one is cylindrical, has its spades pointing straight back and has an adjustment nut arraignment on the nose.
Generally speaking, if your car came from the factory with a sway bar, it will have the HD brake switch
 
Tony,
All I know is it is the push in type,the adjustable nut one is NG! Brakes are factory Front discs, shoes on back
 
What really helps when asking such questions is photos. Otherwise, nobody knows what your original and new switches look like.
 
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