spongy brake pedal adventures

[harry3]

my VL 6cyl berlina wagons brakes dont look too bad but a rear wheel cylinder showed signs of leakage so I finally got around to getting both rear wheel cylinders replaced and all brake fluid replaced ( the fluid absorbs water and can allow rust and corrosion in the hydraulics)

It also had a very spongy pedal ,the brake bloke remembered VL s from new and said the pedal on models with rear drum brakes was lousy and spongy from new, I hoped some air trapped in the system was responsible but he doubted it

so the pedal is now a bit less spongy, brake bloke said this was a common compaint but the VL V8 and turbo models with their 4 wheel discs had a better master cylinder that wasnt spongy


going back I remember a HT holden with a very spongy pedal from new

[gungazza]

ive got the same prob ,i adusted the handbrake ,as per the manual ,and it made a bit of an inprovement ,try that and see how thay go.

[VL Berlina 5speed]

my VL 6cyl berlina wagons brakes dont look too bad but a rear wheel cylinder showed signs of leakage so I finally got around to getting both rear wheel cylinders replaced and all brake fluid replaced ( the fluid absorbs water and can allow rust and corrosion in the hydraulics)

It also had a very spongy pedal ,the brake bloke remembered VL s from new and said the pedal on models with rear drum brakes was lousy and spongy from new, I hoped some air trapped in the system was responsible but he doubted it

so the pedal is now a bit less spongy, brake bloke said this was a common compaint but the VL V8 and turbo models with their 4 wheel discs had a better master cylinder that wasnt spongy


going back I remember a HT holden with a very spongy pedal from new

yes drum brakes tend to be like that, really spongy and feel the lack of power to stop.

the better master cylinder on the vlt/v8 is the 1", it just allows more fluid to be pumped though the lines with the same effort.

[harry3]

I still have to push the pedal a long way before the brakes work, can any adjustment be made to fix this?

[gungazza]

did you try the handbrake adjustment

[harry3]

I will but I cant see how it would make a difference, the handbrake cable seems to stretch a lot, something of a tradition for holdens

[richardsworkcar]

If its nearly to the floor it could be the brake booster, (what the master cylinder bolts to) the are vacuum operated and sometimes require a new diaphram. Id get another brake guy to check it out pedal should be half way down only.

[KRUPTD]

If your pedal goes to the floor it aint goin to be a booster problem,more than likely its got air in the brake system or the seals inside the brake master cylinder have perished and are mushrooming as you apply the brakes thus letting the brake fluid to go past the seals,and also if it is drums the rear shoes need to be adjusted properly.If you have a faulty booster or leaking one.Your brakes will be very hard to apply.Because the brake booster is a like a vaccum pump/assisted by the engine and helps with applying the brakes.
Also i know early model commodores didnt have a great feel on the brake pedal but try a different brake pad for the front,different compound of stopping material.At work majority of our brake we do we use Bendix and have no problems with pedal feel or noise.cheers

[gungazza]

did you try the handbrake adjustment

how did you go ,did you do the hand brake adjustment /??

[Bax]

That dodgy seals in the master must be what I have.

My brakes work insanely good, but I've got about 1" between barely touching and locked. 1" would be an exaggeration too. It's tight. All happens right on the floor too which isn't cool.

[harry3]

the brake expert says all is OK, the pedal goes about half way down before much happens but doesnt sink once applied, adjusted the handbrake but this made no difference, feels like there is still air trapped in system but brake bloke who can remember VLs from new and says they were always like this for the models with rear drums
said some owners had bigger master cylinders fitted to improve stopping