Drum Brakes failing to work

[Old Red]

i was driving the other day when suddenly i didnt have any brakes. the pedal just went straight to the floor and there was no way to stop it. if you pump the brake it eventually catches and stops.

im thinking about converting them to disc brakes since they have finally (maybe) gone out. But i cannot find an affordable kit for my 1966 f-85.

Any explanation as to what happened and any help locating a good disc brake conversion kit is very much appreciated.

[Jim's rare 80]

Sounds to me like you blew a brake line somewhere. If no loss of fluid, then I'd check the master cylinder. Power, or standard?

[Olds64]

You can check out one of the following websites for disc brake conversion kits.

http://www.discbrakemike.com/
http://www.mpbrakes.com/index.cfm

[Oldsguy]

I would recommend that you just have your brakes repaired, no need for discs.

[Oldsmaniac]

Check your master cylinder fluid level....if its empty you may have to bleed the air out of the system to restore braking. If its not low/leaking somewhere then the master cylinder is bad. Plunger is not compressing the brake fluid. Its leaking by internally. Usually when this happens if you hit the pedal hard you will have brakes but a slow press of the pedal will go straight to the floor.

[redoldsman]

My bet is on the master cylinder. 1966 is the last year before they went to the dual master cylinder. If a line was leaking, the fluid would be gone and it would never pump up. I think Oldsguy has the right ideal about keeping the drum brakes on this car. One thing I think I would do is convert it to a dual master cylinder which would be pretty easy. You would have to do this with disk brakes anyway. It just makes a safer system which is why they went to the system. Good luck.

[Starfire61]

Sure sounds like the master cylinder. How soon do you want to get the car back on the road? How much money do you want to throw at it & how many headaches do you want to have?

The cheapest/easiest/quickest thing would be to repair the existing system. Assuming the wheel cylinders, lines, & other hardware is OK, you're at least looking at putting a new kit in the master cylinder & possibly having it sleeved. If it has power brakes, this would also be a good time to have the booster rebuilt. I recently did this with a '62 Starfire & I'm very happy with the results.

A conversion to a dual master may not be a bad idea if parts are readily available & you're not concerned about originality. I'm not familiar with these cars, but I've heard that some of those dual master conversions also require replacement of the brake booster....do your homework before you start tearing things apart.

I've never quite understood the knee-jerk tendency of so many folks to go through the hassle & expense of putting disc brakes on a lot of these older cars. Sure, they work better, but in the big picture are they really THAT necessary? For a collector-type vehicle that may not be driven much, especially in tough conditions, I think properly maintained factory brakes are quite adequate. You need to think about how this car will be used & base your decisions accordingly.

Chuck

[Oldsmaniac]

I've never quite understood the knee-jerk tendency of so many folks to go through the hassle & expense of putting disc brakes on a lot of these older cars. Sure, they work better, but in the big picture are they really THAT necessary? For a collector-type vehicle that may not be driven much, especially in tough conditions, I think properly maintained factory brakes are quite adequate. You need to think about how this car will be used & base your decisions accordingly.

Chuck[/quote]

Agreed!....It would be different if the car was a daily driver and you were more likely to have a panic stop or two on a regular basis or if you were driving a road course or something. I grew up with manual brakes, single master cylinder cars. You get to know what the braking action is and respond accordingly with foot pedal action, timing and pressure. My 66 Delta 88 has a manual trans and manual single chamber master cylinder. I have never felt I needed to upgrade anything on the braking system. I dont remember ever hearing of any pre 67 GM cars being notorious for crashing due to the single reservoir master cylinder.

[The_Jeremiah]

Sounds like the rear seal in your master cylinder went out. Good luck

[Old Red]

the reason i wanted disc brakes was because this is my daily driver. im 16 and this is my first car. All of the repairs are waay too technical for me so we found someone to do it. ill talk to the guy and tell him everything that you guys just told me. i think im just going to have the system repaired. Besides i just ordered a new carb and manifold so im a little short on money lol.

thanks to everyone for all the replies!

[joe_padavano]

I'll vote on the side of converting to disks. The 9.5" front drums on these cars are marginal at best, especially with at big block. My first car was a 68 VC with drums and I actually had the brake linings come off the front shoes. Every Olds I've had since then received a disk conversion if it didn't already have them.

[Modern Motoring]

Originally Posted by Old Red

the reason i wanted disc brakes was because this is my daily driver. im 16 and this is my first car. All of the repairs are waay too technical for me so we found someone to do it. ill talk to the guy and tell him everything that you guys just told me. i think im just going to have the system repaired. Besides i just ordered a new carb and manifold so im a little short on money lol.

thanks to everyone for all the replies!

First things first, young grasshopper. Make car stop first, go second.

Spend your money on making your car safe first. Go thru and repair or replace parts in the brake system, steering and suspension, lights and signals, U-joints, belts, hoses and then a tune-up. No need to slap on a "Holley 750 double pumper" on a worn out V-8. (hint= stick to the original carb and have it rebuilt. better on gas and less backyard engineering to figure out!)
If this is your daily driver, use this list and do it in order that it is written. Also, buy a shop manual -AND- a Motor manual for the year of your car. Read them cover to cover, then read them again. Be prepared to get into it and getting dirty, this will save you mounds of money, plus these cars are very simple to work on and maintain. You will get more satisfaction fixing up your old car yourself than taking it to a shop every time something goes wrong. (hint #2, old cars need LOTS of maintenance! )

Welcome to the old car hobby, let me know if I can help you out !