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67 fairlane - question about spongy / weak brakes

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brakes
5K views 12 replies 7 participants last post by  FEandGoingBroke 
#1 ·
Got a 67 fairlane 289, manual drum brakes...I inherited it and have just started fixing it up (been sitting for 3+ years undriven).

Details on what we've done: cleaned and rebuilt master cylinder, cleaned old gunked up fluid out of lines, cleaned or replaced necessary parts on all four drums (machine drums, new shoes, new wheel cylinders, and just cleaned the other parts...springs, clips, etc.), fill with new brake fluid and bleed.

Question: after bleeding multiple times and checking that all the fittings are tight, adjusted screw to tighten the shoes, etc...the pedal is still soft and the cars stops, but you have to really mash the brakes. My hunch is that the rubber brake lines on the front from the wheel well to the cylinder are just old and are expanding under the pressure, but not bad enough to bust. Does that make sense or is there something else to try first b/f I go buying new parts?
 
#3 ·
It could be the soft lines, the lines are old and probably should be replaced. Would not be a waste of money in any case. If that doesn't solve it keep bleeding. You can tighten them until the wheels won't turn and they will still be spongy with air in the system.
 
#5 ·
As an owner of 2 67 fairlanes with soft brakes. i can tell u this. in my experience with these cars. the brakes are just soooooooooffffftttt i hate it. i hope other 67 fairlane lovers jump in on this and say other wise but with my 2 fairlanes. one with a booster and the other not. the only thing that fixed it was this. getting a totaly different type of master cylinder (and booster) then what came on these cars. the ones the part stores give you are right to the year; but always soft. ive tried swopping so many out. on the one manual drum fairlane once we bought a off brand updated master cylinder. was the only time ive seen the brakes not being soft. and later we bought a booster from the same company, which made it even better. on my other 67 with a vintage to year rebult master cylinder and booster. still soft.

with what ive experienced, its the master cylinder type.

like this one:
http://www.autokrafters.com/v4/go.g...products&show_product_id=519011&product=23681

or this one:
http://www.autokrafters.com/v4/go.g...products&show_product_id=854435&product=23681

but not this one:
http://www.autokrafters.com/v4/go.g...products&show_product_id=517461&product=23681

which im assuming is the one on your car now?
 
#6 ·
I've been thinking about your brakes.... And I've been thinking about what GTA said.....

None of what GTA said makes sense to me because I've never experienced it.

And you said you have the shoes adjusted all the way out properly.

That leaves few things that will make for soft pedal on a hydraulic brake system.

1: Air in the lines

2: Expanding rubber brake lines

3: Incorrect brake shoes.

I think that if all of the things you said are correct then the issue is the shoes are too small for the drums.

Here's my logic:

a: The shoes push outward from the top to engage the drums for stoppage
b: The brakes are adjusted ad the BOTTOM for snugness

Theory: If the shoes are too small, the distance the top has to go out to meet the drum is increased, this giving the feel of a soft pedal, when it's simply having to overpower the retainer springs in order to get fully seated on the drum to start the actual slowing process. You see the bottoms can be all the way out and touching the drum but the tops have too far to go to give a firm pedal.

Does THAT make any sense to anyone? How does that sound Poontz? By the way, Welcome to Ford Muscle forums.
 
#8 ·
FE has worked on so many more fords then i have, start with his advice. always start with the cheaper option first. that is just my experience. maybe my 2 fairlanes soft brakes are just a coincidence. good luck
 
#7 ·
My brother has a '66 Fairlane (it's been in the family since it was brand new :eek:) and I can tell you everything that was said below is true. Not only are the stock drums crappy (on any car) but they are heavy cars too. Once he swapped in a set of SSBC front disc his problem is 90% gone. I realize this isn't a cheap fix but in the end you'll be much happier. In the mean time get them adjusted properly and I'm sure you'll be better off.

John
 
#9 ·
FE , you got a point about the shoes's to small . not a large difference but when the drums are cut , that enough for the bottoms to hit and the cylinder trys to bend the uppers . cure for it is grind the new shoes to the new drum diameter . thats how it was done in good shops back in the day . in those days a rock hard pedal was common on non P/B's
 
#10 ·
All of my non power cars have a perfectly balanced rock hard pedal and the brakes provide instant friction the second I demand it.

I've been in a car that the brakes went to the floor on ONE TIME while driving and I was so close to my maker that day that I vowed to never be in that position again unless it was my maker calling and you don't ignore him. When that day comes I'm 154% sure that it's NOT going to be my brakes that sent me packing. :D :D

Do this (if you're still here trying to fix your brakes):

Measure your drums across (10.? inches or 11.? inches)

Now measure your brake shoes at rest From the top of the right hand (rear) shoe to the bottom of the left hand (front) shoe in a perfect line cutting EXACTLY across the center of the axle stub.

Now measure the opposite of that like making a big X because that measurement will tell you with a little math how far your brake shoes are from your drum.

If the distance is too far then your master cylinder piston will have TOO far to travel before it contacts the drum surface and THAT TRAVEL area is where your Soft brake comes from, if only you are sure the rear flex hose from the frame to the axle is not expanding.

Thanks for the backup Dan. :)
 
#11 ·
I appreciate all of your comments guys. Sorry, I'm not in the habit of checking the forum and just plain forgot to check back.

We put two bottles of fluid through the system, so it may need more bleeding, but I'm pretty convinced that if there is air in the lines it's being sucked in and not a matter of not bleeding enough.

The car is at my parents' a couple hours away, but I will definitely try your measurements FE...your thoughts make sense, my only hesitation is that the drums after machining where in spec and the shoes were oem replacement. And, I'm a novice at this (a little better than beginner), but I'm pretty sure we adjusted the screw properly...I will definitely try all four again like was mentioned....screw it all the way and back off a click. Thanks again and I will report back.
 
#12 · (Edited)
+1 on what DanH said... if the radius of the shoe does not match the radius of the drum, they'll work like (as FE puts it) schitt.. they'll either touch on the ends of the material or in the middle of the shoe. after awhile, they'll seat and work good.

The shoes are designed with a leading and trailing shoe. The leading shoe hits the drum, and the drum's rotation tries to force the shoe down, transferring motion to the rear shoe through the star adjuster and actually forces the rear shoe into the drum harder...

If you could vent the drums, they would stop just as good as a disc and be lighter in weight.
 
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