Thank you Steve!
I appreciated the booster including new nuts and a push rod bushing.  I bolted it in without a problem in about 2 hours and now I have my old brakes back!  Ah, simple pleasures, like being able to stop when you want. :-) 

I agree that this model seems simpler, without that aluminum/plastic spacer between the booster and master cylinder and with the hole in the front of the booster sealed off.  My problem in diagnosing the issue was that I was assuming I had a good booster after testing it on the bench with a vaccuum pump and it appeared to work.

Thanks to all for the advice and feedback.  Now I'm off for a longer test ride.
Hutch

Hi guys,

I replaced the MC over the past couple of days.  Man, I'm loving that flexible alloy brake line. Bled the brakes thoroughly and adjusted the proportioning  valve all the way in then backed it off a quarter turn.  The brakes were a lot better and improved substantially after they were heated up.  I tested hard braking from about 45 mph and the back brakes locked up pretty early, so I backed the adjuster knob out to 1.5 turns.  That seems to be a pretty good setting, but I'm sure it can be tweaked a bit more because the back starts to swing out to the driver's side once the back tires  lock up.  What are the differences in brake pad composition?  Would I get different braking (i.e. good initial braking, prior to heating up) with other pads?  (Before you ask, I can't recall what type I have on there now, since I replaced them early last year.)

I didn't get a chance to contort myself under the dash to check out the brake pedal, but from memory the pivot point looks to be farther from the push-rod connecter than any of the short ones.
Hutch

Ok, sorry for being dense.  I see now after using a screwdriver to push the piston in that what I thought was the cylinder is actually the piston itself.  The fog lifts... perhaps I need new glasses.

On the last MC, I seem to recall the hole in the piston not being as deep, but I could simply be losing my mind over time.  The MC looks bone-dry in the photos because I cleaned it up prior to bringing into the house.  The replacement part number I was given by Advance Auto is 13-1378, which also is the part number recommended by Summit Racing's website and CJPony Parts when I specify make/model/year/engine size.  Advance says it's a "new" Cardone MC, not rebuilt.

I was unaware that there are different models of the booster and master cylinder that fit a 1969 Mach 1 (different piston sizes, single/multiple diaphragms).  I've only ever had one option available from parts suppliers.  What supplier and part numbers would you recommend?  I just want the normal power braking that was designed as stock for this car.

I don't know how to tell if I have a dual or single diaphragm booster.  Is there an easy way to tell by looking at it?
Thanks,
Hutch

Is this the seal you're referring to?  At the moment it's in the booster and the booster push rod goes through it.

Forgot the picture of the push rod.  Here's how I had it installed...

Thanks for the replies guys, I appreciate it.
barnett468: You're right in that guess.  Although I've had the car for 19 years, I've never really had a reason to go looking for what was original and what wasn't in the brake system.  I found the build sheet under the back seat, but it's tattered and torn enough that I can't make out what was originally in the braking system (disk front or not).

MustangSteve's idea of a binding booster boot (that rolls off the tongue, huh?) is interesting.  I noticed that the boot on the first booster was torn when I took it out and it's difficult to get through the firewall hole.  Same with the booster I installed, after how many times I've had it in and out.

I'll take the driver seat out tomorrow and lay on my back and take some photos.  I clearly remember torque-ing down the booster bolts pretty well - using a universal joint on the ratchet.  Maybe it's in there crooked and/or the hole's too small.  That would be a nice fix if I didn't have to screw around with the proportioning valve and fabricate new lines.  (Well, nice is relative:  laying on my back reaching up under the dash isn't one of my favorite pastimes.)

Thanks for the suggestions everyone, that gives me new things to try.
Hutch

BTW, in answer to a question I missed answering:  The hard spot is a full-stop, not a temporary spot you can push through.  The amount of force I need to apply to get the car to stop isn't linear at all with the braking response - which is now sounding more like something mechanical binding somewhere when it's under pressure (hence it not binding when the brake drums or front pads are off).

After the engine rebuild

I'm another Mach 1 owner that's new to this forum.  I'm also having problems with my brakes.  Here's a summary; I'm hoping someone will have some ideas.

I have a 69 Mach 1 351W that's been stroked/bored to 410 ci. When I first bought this car in 1997, it was a stock 351W.  and the brakes were almost too good.  They were very touchy and took some getting used to when I first drove it after winter storage.  Eventually I needed to replace the booster and decided to also replace the master cylinder at the same time, especially as Rock Auto had a deal on a combination of the two.  The brakes worked ok after that and weren't so touchy.  I had the engine rebuilt and afterwards the brakes still worked ok, this was last spring - just about a year ago.  Around about August, I decided to replace the stock Ford steering and slave cylinder mess with a Borgeson gearbox.

Afterwards, the brakes have a hard-spot in the pedal.  (I can't definitively say that this occurred right after replacing the steering.  That job was an epic adventure because no one at Borgeson knew that a stock Ford power steering pump doesn't supply enough pressure to run their steering gearbox.  Hence I installed and removed the entire assembly 3 times, as I thought I had a bad gearbox - that involved removing the booster from the firewall each time, which I can now do in my sleep).

Current problem:  The brakes work Ok for about the first 1/2 to 3/4" of travel in the pedal.  Light pressure slows the car just fine. Then it feels as though the pedal hits the end of it's travel and I almost have to stand on the brakes to get the car to come to a stop. I have a 18 inches of vacuum at the booster, have tested the booster off the car with a vaccuum pump (it works) and a new master cylinder (a year ago). I even have a 2nd new booster, compliments of Rock Auto, who sent me the first combo booster/MC with a MC that didn't have the tubing holes threaded.  Since I already had the booster installed before

I'm hoping these posts count for the 2 a new user has to make so I can put links to pictures in dropbox in a question I have on brakes.  I tried to upload a picture, but I'm still getting the reprimand that I must first post twice... oh well, consider this post 1



Hutch