While I'm in there - rebuild calipers?

defcon65 · 06-21-2006, 11:33 AM

I'm going to be putting in new pads, hoses and bleeding the brakes - should I rebuild the calipers or just clean them? Car brakes just fine, no problems whatsoever. But the rebuild kits are pretty cheap, and I will have the calipers disconnected.
What's the recommended frequency of a rebuild? Car has 55K and is 20 years old, great shape, no abuse.

Thanks for any replies, Joe

cbeers · 06-21-2006, 12:45 PM

If they have never been done, they most likely could use it. Once you get them off of the car, you can look them over. If they are in great shape, skip it. If not, rebuilds are easy. Just take your time and be CAREFUL when removing the pistons if you are using air. Very effective, but can do some damage if you don't plan appropriately.

I did mine even though they were braking 'fine'. I found almost all dust boots in poor condition once I had the calipers off.

YMMV

-Chris

Dan in Pasadena · Dan in Pasadena's Garage

Hi Guys,
This thread couldn't be more timely. My '76 has 125,000 miles and brakes well - I did however get the right front wheel to lock up for a moment in a panic stop and later wondered why the left one didn't lock up too? Is the piston not able to fully travel in its bore?

I have no leaks from the calipers but there is a pretty good lip in the outer edge so I intend to do pads, lines, rotors and new fluid.

Since my car has many more miles than yours Joe, its calipers MAY have already been rebuilt at some time. I intend to look them over very closely after a thorough cleaning but do you suppose a 30 year old car with 125k miles might NOT have had the calipers rebuilt yet?

I pretty much feel I've got to rebuild them to know for certain everything is working and rust free as it ought to be. Or am I just being too anal?

84toy · 06-21-2006, 03:19 PM

Other may chime in but the way I determine mine is a two way test. First examine the seals, if they are in good shape, check how easy the pistons move in the bore. If they move easy you are "probably" OK.

If it is a car that is new to me and the fluid comes out looking like used motor oil, at a minimum I will flush the system. and if there is any hint of a stiff piston, I overhaul.

I usually use a C clamp to retract the piston back in the bore when installing new pads. It shouldn't take more than 2 fingers tightening the C clamp if that makes sense. Once the pistons start moving in the bore, you can almost use your hand to push them in. Any tighter is a sign of dirt and corrosion and you should rebuild. Hope that answers your question.......

Dan in Pasadena · Dan in Pasadena's Garage

Paul,
What you describe is exactly my intention.

I once bought a '57 Chevy short bed truck to hotrod that had been a school district work truck. They had done regular maintenance on it and nothing more. The brake fluid came out BLACK! I pumped and pumped that sucker through with clear clean fluid until it came out as clean as it went in....THEN I took the wheel cylinders off and rebuilt them. Interesting thing is they looked pristine inside! They just NEVER changed the fluid, apparently for years.

What tips me my calipers MAY have never been rebuilt is small patches of mild surface rust on the caliper visible through the wheel openings. Guess we'll see when I yank the wheels off!

defcon65 · 06-21-2006, 03:57 PM

Thanks for the tips, Paul S., that is exactly the info I was looking for. My inclination is to do it anyway, but if they are OK, maybe I can wait. The flush, pads and hoses will bring it up to snuff, but you know, there is always the temptation to BUY MORE PARTS. It's sick, and I mean that in the good way.

Joe