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caliper piston tool

TomMull

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Looks good. Have as many caliper, brake tools I can get. Never had a problem since. Price is decent.
 
I get the part about spreading the piston, but looking at the tool I can't visualize how it would help getting the pistons out, a little air works great. I have never had much trouble getting pistons out, the tricky part, for me at least, has been fitting the rubber dust shield to the piston and caliper.
 
I get the part about spreading the piston, but looking at the tool I can't visualize how it would help getting the pistons out, a little air works great. I have never had much trouble getting pistons out, the tricky part, for me at least, has been fitting the rubber dust shield to the piston and caliper.

I don't know if, or how it works, either and was hoping someone was familiar with it. The pistons do come right ou if they have not been sitting for more than 40 years. I've tried compressed air, compressed grease, heat (boy is that unpleasant) with only limited success. Perhaps I have all the bad ones. Or maybe someone has another trick? Tom
 
Looks like the two aluminium "claws" can be turned away from each other inside the piston
It would give an arm to "wiggle" the priston out

DIY project for a winter evening ;-)
 
Yup.

Tom said:
I don't know if, or how it works, either and was hoping someone was familiar with it.

The Allen wrench is used to widen the jaws (with the threaded rod) to grab the I.D. of the piston, the longer arm then gives you a mechanical advantage to twist the piston back and forth as you retract it from the caliper body.
 
Tom, can you get the piston out enough to get some weasel pee on it to soak around the piston? Possibly get some in the fluid chamber? If you could get some of that stuff in there tapping the caliper lightly with a hammer to shock it and let some travel around the piston might help. PJ
 
Tom, can you get the piston out enough to get some weasel pee on it to soak around the piston? Possibly get some in the fluid chamber? If you could get some of that stuff in there tapping the caliper lightly with a hammer to shock it and let some travel around the piston might help. PJ

Good suggestions, Paul, but the piston has become one with the caliper. I do have some good ones but would like to resurrect a couple that are completely stuck. Probably the bores are beyond repair even if I could get them apart. Tom
 
"weasel pee"-----:lol:
 
Good suggestions, Paul, but the piston has become one with the caliper. I do have some good ones but would like to resurrect a couple that are completely stuck. Probably the bores are beyond repair even if I could get them apart. Tom
I disassembled a set of calipers from a car that sat nearly 30 years in a field. What I ended up needing to do was, after breaking them in two parts, was heat the piston until the remaining fluid steamed out the holes, then tossed the halves into a bucket of cold water. Three of the sides only needed this once, the other needed it twice. But in all cases broke the postons free and I was able to twist them out.
 
I disassembled a set of calipers from a car that sat nearly 30 years in a field. What I ended up needing to do was, after breaking them in two parts, was heat the piston until the remaining fluid steamed out the holes, then tossed the halves into a bucket of cold water. Three of the sides only needed this once, the other needed it twice. But in all cases broke the postons free and I was able to twist them out.
Thanks, Mike. Interesting. I'll give that a try in the spring. Nothing to lose. Tom
 
Does seem to work since a professional brake shop gave them back to me saying they couldn't get them out. But be aware once they go into the water you're committed since the colling will pull water into the passages and piston chamber so the pistons will need to either come out so you can dry everything or rust will flash over inside. But as I said, it did work for me. Took 2-3 hours to do the four sides of the pair.
 
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