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flyinthermals
08-10-2013, 12:03 AM
I noticed smoke coming from the brake light switch that is threaded to the power brake booster. I unplugged the two wires going to the switch and the lights went out. The brake lights were on since yesterday and had drained my battery. There is no oil puddles underneath. The reservoir is full. The brake pedal returns to the top position very slowly with the car running or off. It makes a squeaking sound. The pedal is stiff but travels to the floor with the car off and soft and spongy with the car running. I am wondering if the brake booster has failed. I'm not sure where to start. Thanks to all that reply.

Rob

simplyconnected
08-10-2013, 03:49 AM
These switches commonly fail. Check out rockauto.com...
1962 FORD THUNDERBIRD 6.4L 390cid V8 : Electrical-Switch & Relay : Brake Light Switch
AIRTEX / WELLS Part # 3D5
Price US$2.65/each

I'm sure most of the auto parts stores around your area will have them (or can get them in a day or so).

These switches have a pipe thread and they unscrew. You can do it yourself or bring the new part to a mechanic.
BTW, keep the wires far away from ground or it might blow a fuse. - Dave

flyinthermals
08-10-2013, 08:41 AM
I am thinking that the switch done its job and kept the lights on because the brake booster failed. The switch is probably gone now from heating up due to the battery drain.

jopizz
08-10-2013, 11:00 AM
I would first take the master cylinder off and see if you have any fluid in the booster. A spongy pedal usually indicates a master cylinder leak. Even though the master cylinder is full even a small leak can cause air to go past the seals.

John

simplyconnected
08-10-2013, 03:50 PM
Brake boosters fail in a few ways:
Usually the brake pedal gets hard to push or it leaks vacuum (you can hear vacuum leaking when you pull the M/C).

If brake fluid fills the booster, you have two problems. The M/C is leaking and the booster is leaking.

Do John's suggestion. If everything looks ok, clean off everything, replace your switch and bleed the brake lines.

If you troubleshoot from that point, the problem may be more evident.

flyinthermals
08-10-2013, 07:26 PM
Can the switch failing cause the brakes to fade and be spongy? I thought that the brake booster may be the problem and the switch was activated and stayed on because of it. And it was the brake lights staying on that drained the battery.

Also the brake light switch is threaded into the front bottom of the brake booster instead of how the manual shows it to be on top of the master brake reservoir. What year could these parts be from?

shafe
08-10-2013, 11:32 PM
Can the booster be bypassed? The a.c. and all ac components were removed years ago...booster is bad and under dash, can I bypass?

jopizz
08-11-2013, 11:12 AM
Can the booster be bypassed? The a.c. and all ac components were removed years ago...booster is bad and under dash, can I bypass?

The booster can be bypassed by plugging the vacuum line at the intake manifold. You will then have basically manual brakes.

John

simplyconnected
08-11-2013, 03:06 PM
I noticed smoke coming from the brake light switch that is threaded to the power brake booster...

...Also the brake light switch is threaded into the front bottom of the brake booster instead of how the manual shows it to be on top of the master brake reservoir...

Now that I've read this twice, it must be for real. I've just never seen a setup like that. Can you show a picture of your booster and brake switch?

Here is a stock brake switch:
http://www.rockauto.com/getimage/getimage.php?imagekey=4589061&imageurl=http%3A//www.rockauto.com/info/Airtex/3D5.jpg

The only other setup I am familiar with is a mechanical brake switch, mounted at the brake pedal support. I am still wondering how on earth your brake light switch could work off of vacuum. I gotta see this... - Dave

flyinthermals
08-11-2013, 06:49 PM
I was mistaken. The switch is where it should be. I was thinking of something else. I hope the fix is as easy as installing a new switch. The brakes seem a little spongy and return to the top very slowly???

simplyconnected
08-12-2013, 02:13 PM
What, no pictures? Then, I can't see what you are seeing. Your last post confuses me because now, I don't have a clue as to what the problem is.

Did you follow John's advice?
Did you change the brake switch?
Did you bleed the system?

We just enjoyed a beautiful summer weekend. - Dave

jopizz
08-12-2013, 02:47 PM
Dave,

Don't you just love it when people ask for help and totally ignore your suggestions. Maybe if they were forced to pay the $20 membership fee in order to ask for help they would be a little more considerate.

John

Yellowbird
08-12-2013, 05:02 PM
Dave,
Not to hijack the thread but our local paper had a picture from the car show at Ford Headquarters in Dearborn. The picture was of Henry Ford II handbuilt prototype '64 Mustang. Since it was a nice weekend did you get to go?

Again I apologize for hijacking the thread.

Leonard

simplyconnected
08-12-2013, 07:02 PM
Yes, John.. the ones that rip me are guys who sign up, post a technical question that takes some doing to research, then they never sign back on to read the answer.
You're right, sometimes that's what we get for offering free help.

Len, you sparked a few things in my head. I know the picture you refer to and it makes me laugh every time I see it.
The Mustang project was put on ice for SEVEN years before The Duce finally allowed Iacocca to go ahead.

Mustang prototypes were made in 1955 & '57. But Ford suffered a tremendous financial blow from the Edsel which made The Duce mighty gun shy. His quote to Iacocca was, "This better work." Boy, did it.

Even though the Mustang was a huge success, Ford still hated Iacocca, and put his office miles away from World Headquarters. History shows, Iacocca didn't stick around Ford Motor Co., too long after the Mustang's debut. In fact, I worked in Manufacturing Development, two doors down from Lee. We used to see him a lot. It seems every time we did, heads were pared. Then he left for Chrysler Corp.

Now, we get to see the pictures of Henry smiling with a Mustang. - Dave

EDIT: Len, I started working at Ford over forty years ago. Robin & I kept a 'family' membership at Greenfield Village for decades. Now that they raised prices by over a third with NO discounts for employees or retirees, we don't hang around Dearborn much any more unless we're directly involved in some activity.

flyinthermals
08-12-2013, 09:59 PM
Wow... heavy pile on. I try to post and respond when time allows. I work a lot and the kids take much of my time. I havenít figured out how to post pictures yet. Shame on me. It has only been 2 days and I will buy the light switch when I have time to find one. As for following advice, I certainly try to follow advice to things I donít know about. That is why I ask the question in the first place. The lighting in my underground is very poor and it's hard to see. Sorry If my lack of knowledge on the Tbirds or car is general has rustled anyoneís feathers. Iím simply trying to tap into the collective minds of hundreds if not thousands of years of knowledge. I thought that is what this site is for. To ask questions for the the benefit of everyone. And yes I am a paid member. I will promise to keep my questions in the future to a minimum as not to irritate anyone here.

Cheers

scumdog
08-13-2013, 04:16 AM
Wow... heavy pile on. I try to post and respond when time allows. I work a lot and the kids take much of my time. I havenít figured out how to post pictures yet. Shame on me. It has only been 2 days and I will buy the light switch when I have time to find one. As for following advice, I certainly try to follow advice to things I donít know about. That is why I ask the question in the first place. The lighting in my underground is very poor and it's hard to see. Sorry If my lack of knowledge on the Tbirds or car is general has rustled anyoneís feathers. Iím simply trying to tap into the collective minds of hundreds if not thousands of years of knowledge. I thought that is what this site is for. To ask questions for the the benefit of everyone. And yes I am a paid member. I will promise to keep my questions in the future to a minimum as not to irritate anyone here.

Cheers

Nah, you post as you see fit - let the others mold around you...

simplyconnected
08-13-2013, 04:41 AM
Wow... heavy pile on. I try to post and respond when time allows. I work a lot and the kids take much of my time. I havenít figured out how to post pictures yet... Whoa, Cowboy... I know the old saying, "If the shoe fits, wear it."

This shoe doesn't fit you. John was talking about NON-paid members and so was I. Go back and read our comments. If you notice, John and I answer ALL the technical threads.

I can help you post pictures if you need some direction. Ray Clark can too. In fact, there are a lot of us who would gladly help you. Just tell us what you're having trouble with. The Help Desk also has instructions and free software for resizing your pictures.

I know what time restraints and pressure are. Robin & I raised seven kids. Now, I'm retired from Ford's assembly plant in Dearborn. Robin still teaches children at risk in the hood.

I know what pressure at work is all about, too. All of our lines are variable speed. Time Study goes around with the UAW adjusting them according to the work force on a regular basis. One day, two hours after startup, a 150 foot conveyor went down in the Trim Dept. The motor was running but the variable speed clutch wasn't getting power from the Louis-Allis Controller. Men were manually pushing Mustangs down this dual strand chain conveyor just to keep production going. In the mean time here comes the Plant Manager, Assistant PM, Dept. Manager, Maintenance Manager, all the Engineers, all the Dept. Foremen and the tradesmen, all standing around this dead conveyor drive. Guess what, no spare power supplies. They're asking ME if I can get them going or should they send the whole plant home. That's 1,500 workers (and 1,500 families). More importantly to management, it's 300 Mustangs that wouldn't get built (or sold). Is that pressure? You gotta be there to appreciate the weight of the situation because NO help was coming and each minute they lose a Mustang. What to do...

I got my big boy pants on and stole a Foreman's buggy, pulled the seat up and ran that conveyor clutch off the bank of six volt batteries. 24 volts was too much. It made the line go too fast, so I dropped one battery out and ran it from three batteries, at 18 volts DC. Still, the line was slightly fast, but close enough. The Utility Relief Men helped everyone keep up along the line. Two hours later, we had the parts needed. By the time the afternoon shift arrived, things were back to normal. All the other Engineers were scratching their heads in disbelief, wondering how a conveyor could run off an electric go-cart. It's just another day of slaying dragons at the factory. Nobody went home early and Ford only lost sixteen Mustangs that day. I went home with a smile. So did the Plant Manager.

Bottom line is: Things aren't as bad as you think if you lighten up and allow yourself to think outside the box. - Dave

jopizz
08-13-2013, 12:05 PM
Your original post indicated that you had a spongy pedal in addition to your brake light problem. I told you that I thought it was a master cylinder problem. You subsequently posted twice after that about a spongy pedal without acknowledging that you checked it or even were going to check it. Whether or not you are a paid member if you ignore people who are trying to help you don't expect to get much help in the future. All of us are busy. That doesn't mean we can't take time to be considerate.

John