Rhode rover

Active Member

• Wednesday at 01:28

• #1

I was hoping someone would recognize this electrical part mounted on the brake servo mount thru the small removable panel. It connected to nothing. I removed the small panel and there's only what looks like a sort of trigger that adjusts as to the depth the unknown part is screwed in .

 

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layfin

Active Member

• Wednesday at 02:03

• #2

Brake Light switch, although I have not seen one like that before.

 

tottot

Well-Known Member

• Wednesday at 08:56

• #3

Likely something put there to fill the hole if not connected.

 

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layfin

Active Member

• Wednesday at 11:01

• #4

Do the Brake Lights work.

 

Rhode rover

Active Member

• Wednesday at 12:31

• #5

I knew someone would know. Honestly my auto repair knowledge is limited but this insight helped.
I knew the mounting position was on the brake servo, what I didn't know or believe now was that it must have been an add on or special order when made. I don't think a servo was standard equipment.
Also, reading the general location of a brake light switch is on the brake pedal under the dash. On the other hand I read at times the brake light switch is mounted brake servo bracket like it is here.
The switch sat there unconnected but I did find 1) set of wire clips green with purple (brakes) and other green (ground). At least I think I'm correct. That is linked to other wires ( generic white) with clips that might connect to brycrest choke safety switch to supply power and all that leads into the dash, yet to be explored.
I know I'm rambling, just trying to sort out my thoughts

 

Rhode rover

Active Member

• Wednesday at 12:45

• #6

I'll have to get assistance to check if there on

 

Rhode rover

Active Member

• Wednesday at 12:46

• #7

The switch is a gm part.

 

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Wildefalcon

Well-Known Member

• Wednesday at 17:24

• #8

The later series have servos, and a switch in the engine compartment. Mine is like that, not that exact type of switch, though. Surprised the bonnet closes!

 

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Rhode rover

Active Member

• Wednesday at 19:32

• #9

I must be wrong about the availability of the brake servo during 1973, I'd like it to be OEM. I know it's a GM switch( most likely cheaper). On this unit, one side goes to the brake and other for a torque converter.
I think the previous owner might have tried to the choke safety switch in a daisy chain effect.

 

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Wildefalcon

Well-Known Member

• Wednesday at 19:49

• #10

I think it was an option. Parts book is your friend. But not sure if it was the same as the post 1980's system.

 

steve2286w

Well-Known Member

• Wednesday at 20:08

• #11

book shows various options for switching on the brake circuit , mine had the warning light in centre console , not seen it on for years though

 

Rhode rover

Active Member

• Wednesday at 22:54

• #12

Thanks for the help

 

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Wildefalcon

Well-Known Member

• Thursday at 12:19

• #13

Be careful fitting a replacement, they are finicky to get right unless you read the manual.
I broke the switch the first time I replaced mine, many decades ago.

 

Last edited: Thursday at 12:33

Rhode rover

Active Member

• Thursday at 19:03

• #14

Thanks for the warning. I did order what I believe to be the correct switch.
My new question is, before reading the Green Bible, is the actual depth the switch screwed into the plate strategic to it working properly. The plastic unit was loose, easy to move...almost by itself.
I'll practice and try to get the results I'm looking for before mounting the new part.

 

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Wildefalcon

Well-Known Member

• Thursday at 19:23

• #15

That's where I went wrong. You barely screw it in at all.

 

Rhode rover

Active Member

• Thursday at 21:07

• #16

I looked at the one I bought, it seems to have a locking nut to maintain its position. The present one does not.
As I remember there's a adjustable trigger or lever action that fits into the upper main housing of the servo mount frame. Is that where I make the adjustment between 19 - 25 mm of pedal movement.

 

samc88

Drivels spiritual representative

• Thursday at 23:35

• #17

Ive never got on with the servo brake switches (went through 3 in a month of varying brands but unvarying poor quality). I ended up fitting a defender push to break brake switch to a bracket above the brake pedal. It was a temporary fix about 6 years ago and it works so well Ive not bothered sorting out a proper fix

 

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layfin

Active Member

• Thursday at 23:47

• #18

The new switch is positioned just barley touching the pedal keeping the brake lights off. When you depress the pedal the switch will open and activate the brake lights. Make sure you lock it in place with the lock nut.

 

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layfin

Active Member

• Friday at 08:14

• #19

The only things attached to the Servo are the Brake Master Cylinder and a Vacuum Pipe connector. Mine is a 1984 109 FFR peteol. From memory I think the white wire connected to a Choke Indicator Switch which I discarded or else to a Solonoid on the Carb which I also removed. The 2 other wires you mention are for the brake light switch which is mounted behind the Servo and directly above the Pedal

 

Rhode rover

Active Member

• Yesterday at 11:47

• #20

Gentlemen...your the best. I followed your advice and everything works perfect with the older original after market part. Well almost everything, the yellow cold start light that wouldn't work before now won't shutoff. Some research said it cause was a improper ground but hey you do it all at once.
Thanks for the help.