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Discussion Starter #1
i have a 1976 hease, based on the 76 fleetwood (500ci). Recently when i brake i can allmost put my foot to the floor before brakeing starts. what should i be looking at to repair, master cylinder?

thanks,
Nik
 

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1999 STS - diamond white
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Check your fluid level. Is it topped off? Does pumping the pedal restore power? Any leaks around the wheels or other brake system parts?
Give us more to go on.

What's a "hease"?
 

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Discussion Starter #4
yea sorry hearse on a commercial-limo chassis.

fluids are topped, and pumping the brake doesn't seem to have much affect. And no leaks.

thanks.
 

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Discussion Starter #6
i'll give that a try, some one else suggested bleeding to try to make sure there is no air in the system.

what is a proportioning valve?
 

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2015 Mazda3 S GT Hatchback 2013 Kia Optima SXL
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Do not just bleed the brakes. Replace all of the old fluid. Bleeding only removes some of the old fluid. The funny thing about brake fluid, it absorbs moisture. That turns it into a sloppy mess. Replace all of the fluid, and go from there. If is is still mushhy, it may be a bad brake line. The rubber gets old, and will expand when braking, which is not good. These are your two main areas to attack first.

Don
 

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Pumping the brakes will restore the pedal if it was an air-in-the-line problem. You either have a bad master cylinder or the vacuum booster isn't working.
 

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1976 Eldorado project
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EcSTSatic said:
Pumping the brakes will restore the pedal if it was an air-in-the-line problem. You either have a bad master cylinder or the vacuum booster isn't working.
He's got Hydroboost though, right?
 

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94 Eldorado, and a 99 ETC
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No, it's DEFINATLY NOT a power booster problem. A power booster problem would do the exact opposite of the problem he's describing. If it was a power booster problem, the pedal would be very firm but you will have very little stopping power.

Pumping the brakes will NOT restore firmness to the petal if there is air in the line. Pumping the brakes releases the vacuum from the booster so it may get a little more firm, but not much.

It could be (in no particular order):

1. a master cylender problem
2. a bad proportioning valve
3. air in the line
4. a leak
5. old rubber brake lines
6. internal leak in a caliper
7. bad cylender in one of the rear drums <-definatly check for this one
8. poorly adjusted rear drums

I think thats all of them... :hmm:


EDIT: Yeah I forgot one... It could also be the metering valve.

ANOTHER EDIT: It is good to flush out all the brake fluid once in a while like Dadillac said. This prevents the lines from rusting on the inside. Although, water is a liquid, and liquids can't be compressed. Therefore, diry brake fluid will not soften your petal. It may however reduce the life of your brake system, and could cause this problem in that respect.
 

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Discussion Starter #12
thanks for all the good info! i'll try replacing the fluid and look around for bad lines and anything amiss this weekend.
 

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76CaddyHearse said:
thanks for all the good info! i'll try replacing the fluid and look around for bad lines and anything amiss this weekend.
That's a good thing to do regardless of a problem. Moisture in the lines drops the boiling point of the fluid. if you overheat the brakes on twisty roads for example, the fluid can boil over.

Please let us know what you find wrong with your brakes.
 

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did this just happen or did u have brake problems before....I would jack the car up and have someone step on the brakes and try to turn each wheel....see which side,frt or rear is not holding....while someone holds the brake pedal down,look at the brake hoses to see if they are ballooning out...
 

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Hello: I one week ago picked up a 1979 sedan deville 89000 miles, body no rust,no dents trans slips a bit dash and seats cracked, runs good.385.00 I found out today that this car has rear disc brakes,how can that be?

Thanks
 

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Discussion Starter #18
thanks this weekend i'll be getting under it looking around and bleeding the brakes if i don't see any thing obvious, thanks for the pointers!!!

79 deville, my hearse has drum brakes in the back, maybe some one put discs on the back? maybe the deville came with them? dunno... i'd think that would be a plus having them in the back too.
 

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Discussion Starter #19
Ok it looks like I've found some more symptoms of my problem after putting the car on jack stands and taking off the wheels...

1.) back breaking by the hydraulic system is non-existent. With the car running and the break peddle to the floor the rear wheels spun freely. the emergency brake does lock up the rear drums. I tried to pull the rear drums off but I couldn't get them off over the shoes (I pulled and banged like hell but the best I could was to get them about half way, yea, I had the Ebrake off, any suggestions?)
2.) beading the rear breaks, with the bleeder valve wide open, I got almost no fluid at all (with the car on and off and stepping on the peddle) a friend gave me a suction pump and I got only a few drops with that.
3.) the front rotors are wiped out, big deep gouges in them despite the disc pads still had some life (obviously, I guess, from the over stress of not having rear breaks)

Suggestions? would you think my proportioning valve needs to be replaced or does it sound like I could have a clogged or collapsed break line in the rear (the line seems to be all metal going to the rear with a small part rubber to the rear axle, looks good...)?

Oh, and the little bit of fluid that came out of the back looked milky and dirty, the fluid in the master cylinder looks OK, I'll be changing all of the fluid once I find the source of this problem.

thanks for all of your suggestions!!!
 

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With those new syptoms, it is definatly not the proportioning valve, and I don't think it's the metering valve (if it was, the same thing would happen, but to the front). For the drum, you just have to keep trying. Take a big flat-head screw driver and pry it, while you are hitting it with a hammer, and alternate sides. It should come off, even if only little by little.

I think, the most probable cause to your problem, is leaking cylenders in the drums.
 
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