Do calipers develop slow leaks or completely fail?

chrisp · 05-28-2005, 04:23 PM

My calipers are original, never rebuilt. I don't want to have a massive failure due to age of seals etc. Will they totally fail or just start to develop sticky pistons, slowly leaking seals, etc.?

johnsjmc · 05-28-2005, 04:45 PM

Usually they fail slowly over time. Sticking after periods of storage and or leaking when used again. Rebuild is easy and not very expensive unless pistons are badly corroded needing replacement .

chrisp · 05-30-2005, 05:37 PM

thanks.

aigel · aigel's Garage

If they are indeed from 83, just put a rebuild on your to do list next time you would bleed the brakes or do other brake work like new rotors or pads ... a rebuild kit is in the tens of dollars. John is correct, I don't know of any catastrophic failure. It is a slow deterioration, so there is no hurry if your brakes are ok now.

George

chrisp · 05-31-2005, 06:03 AM

How long can a first timer (to brake rebuilds that is) expect it to take per caliper? I have access to compressed air.

Gunter · Gunter's Garage

Do a search for the rebuild project on this board, it gets involved. What happens with age is that the pistons freeze (rust-up) inside the calipers meaning: The pistons do no longer retract properly meaning: The pads are contacting the rotors all the time slightly meaning: Heat and a little loss of HP. Get the Bentley manual or, take the calipers off and go for a rebuild set/exchange.

B D · 05-31-2005, 07:28 AM

Quote:

Originally posted by chrisp
How long can a first timer (to brake rebuilds that is) expect it to take per caliper? I have access to compressed air.

First one will always take the longest, you will playing with clamps and spacers to get the pistons almost all the way out together. After you got the steps down around 30 minutes per caliper to remove the pistons, seals, and put them back together. If they are stuck and in bad shape it may take longer.

The tech article on Pelican is a great resource.

gost · gost's Garage

Yes first one is the longest. I just removed mine out of an 85 and used the compressed air and C clamp method and it worked great. Make sure you use a small block of wood and put it between the pads when you are about to pop them out. They poped out like bullets on mine. Clean only with alcohol, brake cleaner or hot water with laundry detergent, nothing else no engine degreaser and no parts washer solvent, I just went through this so listen!

Good luck

qcwang · 05-31-2005, 10:02 AM

HI ChrisP,

I agree with gost and BD that the first one is the longest. Took me about an hour and then about 30 minutes. Was really anal on the first one since I had never done it before. In the end it was very easy from what I had anticipated.

Be careful with compressed air. A tire pump was sufficient in my case. Used a wide inflating attachment for beach balls worked and do use a piece of wood in between the pistons as they do pop out with considerable force. I just made a 20 degree template with cardboard to align the pistons and had great results.

Have fun!!

911pcars · 05-31-2005, 12:41 PM

Added safety precautions.

Wear eye protection and cover the caliper with shop towels while applying air pressure. You do not want brake fluid spraying into your eyes, or worst yet, onto your paint job.

Sherwood

gost · gost's Garage

Sherwood is absolutely correct. Forgot to mention that. Good call. I got a misty fog lingering for a few seconds as well..cooool.