weak brakes??

[turbojaeger]

Before i started the restoration i had a little problem with my brakes..

whenever i stopped, at a sign or traffic light, the break-pressure
went down so i had to release it and push again.
i changed the brake-fluid completely in case there´s water in
the system but that didn´t really help. and i also discovered no leaks.

any ideas for the reason???
maybe a bad Brakebooster?
:confused4:

[Robroy]

In case you need to push the brake pedal twice or more (pump the brake pedal) it sounds like you either have air in the system or a leak. The pedal should have a firm feeling when you push it and if it feels mushy you definitely got air in the system.

It could also be good idea to check the hose to the brake booster.

If the pedal goes down a bit too deep than would be considered as normal (about 1”), that indicates you could have worn or badly adjusted brake shoes.
Check the thickness on the front wheel brake shoes, the pad block part should not be too thin, not under ¼” (5mm).

Then continue checking the rear brakes. Get the wheels off and put the gear in neutral. Optimally adjusted drum brakes should have a slight scraping sound when you turn the wheel brake drum by hand which indicates the brake shoes slightly being in contact with the inside of the drum. There should not be any resistance to talk about though!

The drum brakes can easily be adjusted by turning the adjustment wheel which pushes the brake shoes closer to the drum. You can access the adjustment wheel from a little opening in the under part of the shield at rear of the brakes, you just need to pull out a little rubber plug and then use a screwdriver or similar to turn the adjustment wheel.
You can gain a lot of getting down the play in the brake pedal by adjusting the rear brakes.
In your case I would recommend to take of the drums and check the shoes, wheel cylinders etc. Check that the wear is not irregular which indicates you may have a bad wheel cylinder. If you pull out the drum half way and let somebody operate the brake pedal, you can see if both shoes move as they should.
Also when you have the drums off remember to grind off that edge on the outer part of it. That way it’s so much easier to take the drum off when you work with the brakes.

Finally, if you decide to replace the front wheel brake shoes, make sure to clean all parts up and then grease all moving parts EXCEPT the friction parts that get in contact while operating the brake of course, make sure to clean the discs and the contact surface on shoes thoroughly if you should get any grease on them.
It’s also a good idea to exercise the pistons while having the shoes out. Use a suitable item to block the piston going out too far and then push the pedal to make the piston move out a bit like ¼” (5mm). Use a polygrip pliers (found this impossible to translate, see the pict below) and pull the piston back in as far as it admits. Repeat this couple of times so that the piston goes out and in fairly easy.

Good Luck!

[EEE]

:xyxthumbs:

Thanks for the expert advice..

[turbojaeger]

Hmmmm...
i think i´ll find the reason when i get the whole system in parts..
i want to clean everything and replace a lot of stuff like break-booster,
the hoses and lines, maybe the calipers and of course pads and rotors...

that brings me to another question:
what kind / brand of breakpads and rotors do you guys use???

i´m thinking about the Premium-rotors from NAPA ($70) but have
no idea about the pads.
Replacements, organic, ceramic :confused4::confused4::confused4::confused4:

anyone experiences??

[EEE]

When I did my front brakes I think I got everything from Autozone, and it was pretty cheap. Calipers, rotors, pads, hoses, bearings. It worked fine.

[73 CONVERT RON]

Hmmmm...
i think i´ll find the reason when i get the whole system in parts..
i want to clean everything and replace a lot of stuff like break-booster,
the hoses and lines, maybe the calipers and of course pads and rotors...

that brings me to another question:
what kind / brand of breakpads and rotors do you guys use???

i´m thinking about the Premium-rotors from NAPA ($70) but have
no idea about the pads.
Replacements, organic, ceramic :confused4::confused4::confused4::confused4:

anyone experiences??


GO TO EBAY THEY HAVE CROSS DRILLED ROTORS FOR THE 73 FOR ABOUT 90 BUCKS ... I PUT THEM ON MY CAR ITS A HEAVY CAR SO IT CANT HURT TO DO CROSS DRILLED ROTORS I REBUILT MY BRAKE SYSTEM LAST MONTH HEAD TO TOE NEW EVERYTHING ITS NOT A LOT OF MONEY FOR THE PEACE OF MIND YOU WILL HAVE KNOWING ITS ALL NEW :-)