hard braking 1960 356B

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Donald Pirch
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hard braking 1960 356B

#1 Post by Donald Pirch »

I bought the 1960 356B in 2004 and was told it was stored in owners garage for 5 years without moving, with 71k miles on ODO. I have no knowledge of actual total miles on car. Brakes were good after I put it in service as a daily driver going to work for several years. I don't drive it so much now after retirement and it now has 89.9K miles showing.

The brake pedal is really hard to engage the brakes and braking is very poor and dangerous. I recently replaced the shoes on front brakes as the drum material was very hard, glossed over and cracked. I deglossed the rear brake shoes and left them in place. We thoroughly bled all the wheel cylinders. Same problem remains with hard pedal and poor stopping performance.

What is the probable cause of this condition and what is recommended to make it brake properly. My plan is to replace the master cylinder & rebuild wheel cylinders and purge the brake lines w new fluid during bleeding of all wheels. I will have the brake drums inspected and turned if necessary.

KTF,
Don Pirch, PE
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David Jones
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Re: hard braking 1960 356B

#2 Post by David Jones »

Don, with lack of use it is not unusual for the pistons in the slave cylinders to corrode and stick in the cylinders. Before doing anything else pull one drum at a time and get a helper to push gently on the brake pedal and see if both cylinders operate. If only one moves then you have the answer to your problem. Another common error is for the two slave cylinders to be replaced in the wrong position and the brakes shoes installed backwards. That way there is no servo action from wheel rotation and retardation suffers.
The other very common problem is the flex lines breaking down internally and not allowing brake pressure to transmit to the slave cylinders. I would say about 20 years is as much as one should leave the flex lines in place especially if the car was laid up for a while.
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Adam Wright
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Re: hard braking 1960 356B

#3 Post by Adam Wright »

Might also want to check the brake lines themselves, they are like artery's where they look fine on the outside but the inside's close up, like this. This car had the same problem, pedal was very hard, but very little fluid was running through.
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Vic Skirmants
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Re: hard braking 1960 356B

#4 Post by Vic Skirmants »

I've seen them closed down to less than .010".

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Thomas Sottile
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Re: hard braking 1960 356B

#5 Post by Thomas Sottile »

I think Adam is Wright

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John Lindstrom
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Re: hard braking 1960 356B

#6 Post by John Lindstrom »

Sounds like one or more slave cylinders are frozen

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