Brake pedal "feel" on 116 Alfetta

[Craig Sinclair]

I have an issue with the feel and pedal travel on my '75 Alfetta GT& I was wondering if there was anyone with knowledge or ideas that could help me.  I have just replaced the fluid with Castrol SRF & had a set of Lucas pads fitted. I am finding that I have a really long pedal action and not a great sensation of immediatge braking effect. Feels more like a drum-braked Valiant I used to own! Less than satisfactory  Pedal and braking response was the reason I have had the pads & fluids changed, so I'm figuring it must be something else? Any ideas anyone?  Cheers, Craig.

[Beatle]

Craig,

It may be that the brake pistons are being withdrawn a long way into the calipers when you are off the brakes.  This means you need to push the pedal a lot further before the pistons push the pads hard against the discs.

The problem could be worn discs, or even stiff piston boots that pull the pistons back.

It may also be that your brake hoses are soft and expanding under pedal.

I've always found Alfettas have inordinately long brake pedal 'take-up',  though the feel and effect is always good to great.

Check all of the crossover bellcranks that take the RHD braking from your foot over to the booster on the left.  Any wear in this will not help matters.

Adjust the rear brakes correctly, andf confirm that the calipers are actually working.   You could also try a vacuum bleed or a pressure bleed system in case you have a difficult-to-bleed caliper (common).

Oh, and make sure the cutouts in the pistons are rotated to the correct angle.  Do you have an Alfetta manual ?  If not, get back to me and I'll scan the page about piston orientation for you.

Beatle
'66 Super

[Craig Sinclair]

Thanks Paul. I can eliminate a couple of items. The discs were checked for thickness before pads were put in, & the brake lines have been replaced at some time with braided ones. I'll check the rest (I have a manual thanks.) Thanks for the pointers. Craig.

[Colin Byrne]

The problem could be worn discs, or even stiff piston boots that pull the pistons back.

The piston boots are just dust covers, it's the seal that provides most of the piston retraction, I doubt this will be the problem though because if the pistons aren't retracting enough you'll get a very hard pedal. 
I know from the alfetta sedans that you can get a lot of compliance in the breaking system because the master cylinder is mounted to the firewall which can flex giving a very 'spongy' break pedal feel, pretty sure the GT's are the same

[Doug Gould]

Craig

Good luck. I've changed everything in pursuit of a better pedal feel. S/S brake lines, new master cyliner, new brake balance valve, rebuilt calipers - everything without discernable difference. I went to my old standby - BGT brakes in Hawthorn (they used to do all of Harry Firth's work) and they said it just happens that way on some cars. If you look at it the biggest culprit has got to be the cross tube and its mount on the LH side. Bracing the firewall has always been more work than I want to contemplate.

Doug Gould

[Mike]

I've had 4 alfetta's now and when ever I've had an issue with brakes it has always been due to air in the system, its the number one culprit.  Check all joints for possible leaks, and once convinced there are no weeping joints, bleed the brakes with 2 people and patience. 

From experience also, when one part starts leaking in the system, other seals are not far behind. 

Have fun, its such a piss easy job, and yet its the job that always see's me wanting to smash something in the shed

[Evan Bottcher]

The Alfettas all have the handbrake built into the rear inboard calipers yes?  These look essentially the same as the inboard front calipers on the Alfasuds.  I always had trouble with the handbrake adjustment on those calipers.  If you adjusted the calipers up just right then I'd get a great hard pedal, consistent pedal travel etc.  Over time of using the handbrake and a little pad wear they'd go out of adjustment (they're meant to self adjust) and then I'd get a really long initial pedal.  I heard of people who ditched the handbrake mechanism altogether on the Sud calipers to get rid of this problem.  I ditched the inboard calipers altogether.

Just mentioning it in case it's similar for the Alfettas.

[Trent]

Hi i had this problem once before too when i had to replace a gearbox before, therefore i had to replace fluid and bleed the brakes a lot. also did you crack the little brass nut between front and rear lines on the master cylinder?