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Brake light on
- Thread starter labboy
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Scott_Hower
Luke Skywalker
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[ QUOTE ]
My brake light will not go off. I just had a new MC installed and they replaced all the brake fluid. Pads are fine and the emergency lever is fine.
Any help would be welcome.
Thanks
[/ QUOTE ]
Make sure the nose of the brake light switch is screwed in far enough in the pedal box cover. Too far and the lights never go off. Not far enough and they never go on. or maybe vice versa, can never remember if the switch is normally open or normally closed /ubbthreads/images/graemlins/crazy.gif
My brake light will not go off. I just had a new MC installed and they replaced all the brake fluid. Pads are fine and the emergency lever is fine.
Any help would be welcome.
Thanks
[/ QUOTE ]
Make sure the nose of the brake light switch is screwed in far enough in the pedal box cover. Too far and the lights never go off. Not far enough and they never go on. or maybe vice versa, can never remember if the switch is normally open or normally closed /ubbthreads/images/graemlins/crazy.gif
Scott_Hower
Luke Skywalker
Offline
[ QUOTE ]
My brake light will not go off. I just had a new MC installed and they replaced all the brake fluid. Pads are fine and the emergency lever is fine.
Any help would be welcome.
Thanks
[/ QUOTE ]
Oops... which "brake light"? Do you mean the brake lights (rear of the car) or the brake failure warning light on the dash? If the former, look up. If the latter, the shuttle in the pressure differential is off center due to improper bleeding.
My brake light will not go off. I just had a new MC installed and they replaced all the brake fluid. Pads are fine and the emergency lever is fine.
Any help would be welcome.
Thanks
[/ QUOTE ]
Oops... which "brake light"? Do you mean the brake lights (rear of the car) or the brake failure warning light on the dash? If the former, look up. If the latter, the shuttle in the pressure differential is off center due to improper bleeding.
R6MGS
Yoda
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While we're on the subject of that stupid little plastic switch on the bottom of the master....How is that suppose to be installed? I broke one a while back, bought a new one from moss....it's got a slit in the side that allows fluid to slide right past once it's installed. I asume I am missing something here but what? I got frustrated and just pluged it with a bolt and disconnected the light....but i'd like to get it back together properly this summer.
The pressure differential assembly switch typically will not reset itself as do almost all others. You can unscrew the plastic switch and press on the brake pedal to re-center the piston but after all these years it may be seized. The plastic switch is not sealed. If it is leaking there it is because the o-rings in the valve have failed. You need Lockheed kit # LSSB833 which is probably made out of unobtainium. The valve is easy to rebuild on non-booster cars and a little harder on cars that have the switch in the master cylinder though the o-rings come in the booster m/cyl kit. Although the switch has 9/16 flats you should only tighten it finger tight.
Alan T
Alan T
Scott_Hower
Luke Skywalker
Offline
[ QUOTE ]
The valve is easy to rebuild on non-booster cars
[/ QUOTE ]
Mine was leaking through the switch and at one of the bottom flares - flare seat had a nick in it. A rebuild kit is available (all of 2 orings). I bought a rebuilt unit outright from John Twist for $60. Vicky brit wants about $400 for the same part. /ubbthreads/images/graemlins/eek.gif
The valve is easy to rebuild on non-booster cars
[/ QUOTE ]
Mine was leaking through the switch and at one of the bottom flares - flare seat had a nick in it. A rebuild kit is available (all of 2 orings). I bought a rebuilt unit outright from John Twist for $60. Vicky brit wants about $400 for the same part. /ubbthreads/images/graemlins/eek.gif
wkilleffer
Jedi Knight
Offline
[ QUOTE ]
The pressure differential assembly switch typically will not reset itself as do almost all others. You can unscrew the plastic switch and press on the brake pedal to re-center the piston but after all these years it may be seized. The plastic switch is not sealed. If it is leaking there it is because the o-rings in the valve have failed. You need Lockheed kit # LSSB833 which is probably made out of unobtainium. The valve is easy to rebuild on non-booster cars and a little harder on cars that have the switch in the master cylinder though the o-rings come in the booster m/cyl kit. Although the switch has 9/16 flats you should only tighten it finger tight.
Alan T
[/ QUOTE ]
What do you do if the piston's seized? I'm not sure if my system is functional. The dash switch will turn on the warning light, which is good to know. But knowing for sure that the warning system is working would be quite nice for peace of mind purposes.
Thanks,
The pressure differential assembly switch typically will not reset itself as do almost all others. You can unscrew the plastic switch and press on the brake pedal to re-center the piston but after all these years it may be seized. The plastic switch is not sealed. If it is leaking there it is because the o-rings in the valve have failed. You need Lockheed kit # LSSB833 which is probably made out of unobtainium. The valve is easy to rebuild on non-booster cars and a little harder on cars that have the switch in the master cylinder though the o-rings come in the booster m/cyl kit. Although the switch has 9/16 flats you should only tighten it finger tight.
Alan T
[/ QUOTE ]
What do you do if the piston's seized? I'm not sure if my system is functional. The dash switch will turn on the warning light, which is good to know. But knowing for sure that the warning system is working would be quite nice for peace of mind purposes.
Thanks,
The fact that your dash switch works on the test function is a good sign. If you really want to test the failure switch then unscrew it about three threads and see if the light comes on.
Also if you are in tune with your LBC , then you will know there is a problem before it gets to a point that the light is triggered. Either a mushy or low brake pedal.
Alan T
Also if you are in tune with your LBC , then you will know there is a problem before it gets to a point that the light is triggered. Either a mushy or low brake pedal.
Alan T