Technical Hard Brake Pedal - Brake Booster Vacuum?

[jackwhoo]

Difficult to see in you photo but the handbrake cable may be too tight. With the hand brake released the shoe handbrake lever(silver metal lever behind hand brake shoe that pivots at top of shoe) should have a stop point touching the metal part of the brake shoe.

 

[bugsymike]

Difficult to see in you photo but the handbrake cable may be too tight. With the hand brake released the shoe handbrake lever(silver metal lever behind hand brake shoe that pivots at top of shoe) should have a stop point touching the metal part of the brake shoe.

Good point, most of us were taught to back off the handbrake cable and get everything working perfectly at the drum, with best adjustment etc. then if all spinning freely with no brake binding after several hard presses of the pedal only then adjust the handbrake, still with wheels off the ground to ensure nothing is left binding.

 

[Guerciotti]

Thank you for your responses. I have ordered new pre-assembled rear drum brake kit from Febi with all the parts including wheel cylinders. Hopefully this solves the problem.

 

[DaveMcT]

Thank you for your responses. I have ordered new pre-assembled rear drum brake kit from Febi with all the parts including wheel cylinders. Hopefully this solves the problem.

To avoid brake balance problems, you really should always do them in pairs.

 

[Guerciotti]

Hi,
It is a bad idea to press the brake pedal without the drum on ....doing so will most likely push a wheel cylinder piston out of the wheel cylinder further than in normal use causing brake fluid to leak out.
The drum ensures both shoes are applied. There will always be one shoe tjat moves slightly more freely than tje other.when the free moving shoe contacts the drum the slightly less free moving shoe moves until in contact with drum.

With drum on and shoes correctly adjusted each shoe moves less than 1mm before contacting the drum.

Hi, once I have installed the new brake shoes / pistons on both sides how is the best way to test all is ok with the rear brakes post installation given that the drum should be on when pressing the pedal? Is it just a case of checking that the wheel doesn't move when the wheel is in the air and the foot brake is on? Or is there a better way? Thanks

 

[jackwhoo]

Hi,

Your rear brakes are not the cause of the hard brake pedal problem.

I think you would be very very sensible to reassemble the rear brakes and focus on fixing the initial problem-too much effort required at brake pedal.

If you change the rear brakes you could introduce further problem that would confuse matters regarding the real problem.

You could remove the other rear drum and check pistons move using method suggested. do no more than the piston check then reassemble.

You could also check your front brakes.

All symptoms point to defective brake servo

 

[DaveMcT]

Hi,

Your rear brakes are not the cause of the hard brake pedal problem.

I think you would be very very sensible to reassemble the rear brakes and focus on fixing the initial problem-too much effort required at brake pedal.

If you change the rear brakes you could introduce further problem that would confuse matters regarding the real problem.

You could remove the other rear drum and check pistons move using method suggested. do no more than the piston check then reassemble.

You could also check your front brakes.

All symptoms point to defective brake servo

Put car on level ground (or use a chock) and release hand brake. Press the brake pedal and start the engine. If the pedal moves down a little, your servo is probably doing its job.

Check all rubber hoses for age as the linings an fold up internally. This usually causes dragging brakes but not always. For what they cost replace old hoses.

 

[Guerciotti]

Thank you for all of your feedback and assistance. I have decided that I am a little out of my comfort zone and since it is the brakes I have taken it to the local mechanic to take a look.

Thanks again.

 

[jackwhoo]

Hi , I think you have made a very good decision. Make friends with your local mechanic take them a pastry or other snack - you will be amazed at their surprise and they will remember you .
Please let us know what mechanic finds / fixes on your car.
Best wishes
Jack

 

[Guerciotti]

Hello,
Just to give you an update I collected the car from my local friendly mechanic late on Friday afternoon. He said that the problem was related to a faulty ABS sensor at one of the rear wheels. He said he resolved the issue and now seems ok.

As you can probably guess I'm far from being a mechanic but I've got to admit I'm not quite sure I see the relationship with the ABS sensor and the symptoms but the car seems much better now and the Mrs is pleased in getting her wheels back !

Thanks again for all of your help and suggestions.

 

[bugsymike]

Not sure how the initial problem of a "hard brake pedal" etc. relates to an ABS sensor, but if you, your Mrs and your mechanic are happy.....