[jww]

jww jww is online now
Senior Chief Join Date: Aug 2005
Posts: 324

Default Brake ideas/suggestions needed

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Hopefully I can keep this fairly short......

Converted my 62 Catalina from single master w/ power brakes to dual master w/updated 9" power booster. All drum brakes. Have 15/16" of vaccum at the booster.

Have bled system many times and think there is no more air in the system.

Problem is that when I push on the brake pedal there is nothing for the first 2" then the brakes take hold and will stop the car OK. Really doesn't feel like the power assist is doing anything and having nothing for the first two inches of pedal travel is sort of scary and certainly not right..I've tried adjusting the pedal back and forth using the brake pedal yoke, but still has the 2" of nothing! If I get the pedal closer to the floor the pedal hits carpet before the brakes take hold so I have to have the pedal about 6" from the floor so I have a decent amount of good, hard pedal.

This is the end of a 4 year restoration and I have only test driven the car once about two miles so I really have no history to go on here and with the brakes like they are I don't want to drive it much yet!

EVERYTHING on the brake system is new including 8 lug drums, shoes, lines, wheel cylinders, etc., etc.

Can't figure why there is no resistance for that first 2" of pedal travel. Bought booster, drum/drum master cylinder, lines and all from a large, well known brake specialty outfit in Clinton Township, MI. who now could care less that I can't get things to work right!!!.
This system does have a spacer between the hollow brake cyl piston and the push rod coming out of the front of the booster.

What am I overlooking???....any ideas would be GREATLY appreciated.

Thanks, Jerry

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Last edited by jww; Yesterday at 04:40 PM.

[stucky2947]

Since you changed master cylinders and power boosters, chances are the rod that goes in between the power booster and master cylinder is to short. That would cause pedal travel without depressing the master cylinder plunger. Same thing happened to me when I swapped out master cylinders on my '62. I ended up making one. Good luck.

[jww]

Thanks, Stucky.....

Yeah, I thought about that. Just a little space between the rod and piston would probably translate to quite a bit of distance in pedal travel.

Vendor sold me a "slimline" 9" booster and drum/drum master cyl. This type of booster does not have a removable rod and the piston recess was real deep making a distance of like an 1.5" between the two!! They sent me what they called a "slug" to take up that space between the rod and piston but I got a feeling there is still a gap between the back end of the "slug" and the tip of the rod. This rod is not adjustable and it is not removable, according to the vendor.

Guess I'll have to look into this.

Thanks for replying...........Jerry

[64catdroptop]

Did you adjust your brake shoe's out? A small adjustment on the shoe's will make a big difference at the pedal

[stucky2947]

If the 'slug' is removable, take it out and replace it with a slightly longer one. Take note of the ends of the slug. Mine had a little bit of a radius on one end and a dimple on the other end. You can get a piece of steel from any local hardware store (check your slug diameter first), I'll bet it's a standard size, and make the size you need. A little trial and error and you will have it. Good luck.

[jww]

Stuckey and Droptop:

Really don't think it's in the adjustment as I have drums dragging more than I should at this time just to eliminate that as a possibility. I believe the slug/spacer whatever you want to call it is too short cause, I mean, I have no resistance whatsoever on the brake pedal for about 2" then actually have a pretty good, firm pedal that stops the car well.

[jww]

Here's what I found...........

I removed the "slug" that the vendor sent me and drilled the rear of the slug about 1" deep. Threaded this hole and turned in a grade 8- 1/4" bolt and ran this down against the shoulder of the slug.. Countersunk the head of the bolt a little so the pushrod in the front of the booster would rest against the bolt.

Voila!! Full pedal without the 2" of free play......

Hard to believe 1/4" gap in the piston/rod relationship would translate to
2" at the pedal, but that what happened in this instance.

Thanks for all the comments and sugestions....

Jerry Well

[Engine-Ear]

Jerry, any pics along the way that you can share would be GREAT!

Also, glad you have proper pedal.