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Discussion Starter #1
HELP!
I've replaced the 7 of the 8 brake pads on my '84 but am stuck on the last one. One of the front pistons won't go back into the caliper and there isn't room for the new pad.

I've tried to lever the piston back with a thick flat file and broke iot. A big 12" screwdriver and a crowbar won't budge it, either.

FWIW the old pads were wearing evenly and the piston doesn't look crooked in the bore, but it seems frozen.

Any suggestions?

Thanks -

David OD
Laguna CA
 

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Just in case, is there room in the reservoir for the volume of brake fluid behind the piston you are trying to compress?
 

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That piston prolly frozen. You can block up the back, and press the brake pedal to free it — or, Take the caliper off and rebuild it. It can be difficult to do, but getting the piston free Can be tough
 

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David:

ABS Power Brake at 233 N Lemon St, in Orange can rebuild your calipers for a reasonable cost. Even though only one piston is binding, you should at least rebuild both front calipers. Then, of course, you'll need to bleed the brakes - but while you're at it, you might as well change the brake fluid, necessitating bleeding the rears too. Ain't it great how these little tasks escalate into a complete restoration?
 

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Discussion Starter #6
Thanks for the suggestions, everybody.

65 Sprint, yes there is room in the reservoir.

Rogerspeed suggested a 24" crowbar, the Bigger Hammer theory. Gonna try it.

Eric, thank you, I just bought the tool. Delivery Wednesday.

Goats, yes I will try the brake-pedal trick, it's worth a shot.

Jay, thanks for the referral, rebuilding calipers will be plan D. . . . After 36 years, probably required anyway.

David OD
Laguna CA
 

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I had a frozen piston in a break caliper. On the work bench, I soaked for a couple of days with penetrating oil, heated up and use compressed air in the bleeder hole. The piston pop out. Watch out for you hand. You do not want it in the travel path of the piston. The rest is easy. Hone the cylinder, new rubber O rings. If you have time paint always give it a fresh look. Good lock.


Ken Smith
 

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Discussion Starter #8
All done. The 24" crowbar shifted the reluctant piston.

Thanks again, this board's be best -

David OD
Laguna CA
 

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All done. The 24" crowbar shifted the reluctant piston.
Well yes, you forced the piston back and got the new pad to fit in. But, that may not be the same thing as "done". The piston wall is probably corroded or crudded up with dried brake fluid, which is why it was so hard to press in. So that piston may now have difficulty coming back out when you step on the pedal and/or not allow the pad to retract a bit when you ease off on the pedal..

At a minimum, I would recommend putting one of the old, thin pads back in as a spacer and stepping on the pedal to force that piston back out. Then lever it back in with the 24" bar or your new tool. Then repeat a few times. By doing this, you will either burnish the corrosion/crud off the piston, or convince yourself that the thing really does merit rebuilding. Plus, this'll give you an opportunity to use the new tool!
 

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Discussion Starter #12
I 'exercised' the pistons on the reluctant caliper, per Alfajay's suggestions, 5 times. Considerably smoother from third time onwards. Very helpful.

All back together.

Thanks,

David OD
Laguna CA
 

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I 'exercised' the pistons on the reluctant caliper, per Alfajay's suggestions, 5 times. Considerably smoother from third time onwards. Very helpful.
Glad to hear that improved things. Thanks for reporting back.
 
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