possible frozen brake caliper piston.

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84pininfarinablack

possible frozen brake caliper piston.

Post by 84pininfarinablack »

My Front Right Brake caliper i removed today. This piston doesnt move.. I removed the top rubber and am pulling and pushing with all my might as well as a pair of pliers.. .. Should this piston be moving freely ? i would think it would. Can it be unfrozen ? any advice or should i just order a rebuilt caliper from IAP ?

thanks for your help.. trying to put on pads/ rotors/ hoses .. today..
the car had a horrible pull and this could be the reason.
User avatar
kilrwail
Posts: 1100
Joined: Wed Mar 04, 2009 6:49 am
Your car is a: 1978 Fiat 124 Sport Spider
Location: Perth, Ontario

Re: possible frozen brake caliper piston.

Post by kilrwail »

Usually the best way to remove a piston is with compressed air into the brake line fitting - unless it's rusted solid. If you're going to try this, be sure to keep your fingers and eyes protected from the piston when it pops out - it will be a missile!
_____________________________________________________________
Peter Brownhill

1978 Fiat 124 Sport Spider - original owner
1977 Porsche 911S - track car
2022 Ram 4 x 4 - hauler
PCA National Instructor and Motorsport Safety Foundation Level 2 Instructor
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

ill make sure to aim it at someone i dont like.. lol jk ..
i assume it should be free moving that would make sense.. ill get a new one. I must have been driving on one brake pad all week.. sometimes it jerks left sometimes right.. neither of the back calipers bleed properly.. either hoses.. or more frozen calipers.. yippeee


Does anyone know what years calipers are compatible with my 84 spider ? does 79-84 work or does it need to be off an 84?
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

My chassis number is the under (late 84-85) for rotors if that helps.
pooldoctorstl

Re: possible frozen brake caliper piston.

Post by pooldoctorstl »

If the fronts are bad you might want to check the rears too while you have the mess going, and the rear compensator, and the hoses....it never ends once you start. If you do the rears the pistons screw out, air wont work. That is if your 84 is the same as my 82, I think they are.
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

what do you mean by screw out ? it goes straight in and out loosely right ?
pope

Re: possible frozen brake caliper piston.

Post by pope »

The fronts are just pushed in and out, the rears rotate on a threaded shaft. They have to be rotated out.
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

do the backs get frozen too ? or does the screw keep them on center ? Does it unscrew left or right turn ? lol sometimes they are backwards. Who has the best prices on calipers.. ? does autozone or discount auto parts sell them? Or just IAP?
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

auto zone has them for an 82 spider.. will they fit my 84? the prices look to be half price or so from IAP rebuilt ones.

here are the part #s and prices below.. If i buy this will it fit ?

Part Number:
C8082

Price:
$43.99

Core*Core value is the used part that manufacturers use for rebuilding. AutoZone charges the core value to customers because manufacturers include it in their prices. When you return your core to AutoZone, we'll refund your core charge.:
$7.00

Total:
$50.99
Warranty:

LLT
Notes:

Passenger side
STORE PICK UP
SPECIAL ORDER
SHIP TO HOME
SPECIAL ORDER
Fenco Reman / Brake Caliper - Front
Part Number:
C8083

Price:
$43.99

Core*Core value is the used part that manufacturers use for rebuilding. AutoZone charges the core value to customers because manufacturers include it in their prices. When you return your core to AutoZone, we'll refund your core charge.:
$7.00

Total:
$50.99
Warranty:

LLT
Notes:

Driver side
pooldoctorstl

Re: possible frozen brake caliper piston.

Post by pooldoctorstl »

Are we a bunch of losers or what? Sitting around on a Saturday night posting to this forum.....

Anyway, the rears have the parking brake mechanism in them so the pistons are on a threaded shaft. And yes, they will also freeze up. You asked about rebuilding them and getting the pistons out, and front or rear that is the cheapest way to go. I think the kits were about $6 or $7 from Vicks and one kit does both calipers (one kit front and one kit rear). If you do it you will need a cylinder hone available at all parts stores (inexpensive), and a big vice. And make sure you clean out the groove the piston seal goes in because they get a hard, crusty, material in them that has to be cleaned or the pistons will be hard to put back in and they won't move easily and can freeze up again. I think it took me about 15 minutes each to do the front and a little longer for the rear. Once you do the first one, the rest will go faster. You should also get a manual for the rears because you will also have to disconnect the parking brake cable from under the handle and at the calipers.

Buying them is the easiest, but I like cheap.

Jeff
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

at 44 bucks a caliper at autozone im much better off buying brand new calipers instead of fighting with the old ones.
I didnt think i could get them so cheap.
ill try to rebuild one of them.. what do i need a vice for ? cant i just yank rubber. / piston / rubber out ?

no tool bench in my house.. certainly no vice.. that would be cool though.
pooldoctorstl

Re: possible frozen brake caliper piston.

Post by pooldoctorstl »

I guess you could do it without a vice, but if the pistons are frozen it is a lot easier to do it with the caliper secured in a vice, especially ther rears. You are probably right about the 44 bucks for the rebuilts. I think it would be a pretty miserable job without the right tools.
majicwrench

Re: possible frozen brake caliper piston.

Post by majicwrench »

Don't expect the pistons to be a loose fit, or to easily slide in and out, they will be a pretty stiff fit, adn sure as heck aint gonna move with fingers, or a little pair of pliers. A pair of channel locks should get them rotating if they are not siezed. If they are siezed, you're never gonna get em out without compressed air or some serious tools.
Good luck,
Keith
84pininfarinablack

Re: possible frozen brake caliper piston.

Post by 84pininfarinablack »

ok well i went and bought two front calipers from discount auto parts. .

I took the back left caliper off and it does rotate left.. not very easily but it does.. Im considering myself lucky possibly..
I dont have the right tools to unscrew it all the way. Ive never seen the screw driver that is this fat.. I got it to turn 3/4 turn.
should i just put it back into the car and assume it works ? lol Or do you think I should buy another one ? the rubber looks ok.. not great but ok. The parking break looks like a nightmare to unhook from the caliper.

what kind of tool would you recommend to unscrew the piston ? and should i bother ?
rlux4
Patron 2022
Patron 2022
Posts: 4211
Joined: Thu Jan 10, 2008 8:32 pm
Your car is a: 1982 2000 Spider
Location: Granite Falls, Wa

Re: possible frozen brake caliper piston.

Post by rlux4 »

A file that has about the same thickness as the slot in the piston top works good for me. I start it first by using the file sideways, once you've made a few turns it will go easier and you can use the flat end of the file and either pliers or crescent wrench to turn it. This is where a bench vise comes in handy.
Don't screw it in too far, it will damage the outer rubber seal.
Ron
Ron Luxmore
rlux2n2@gmail.com
'82 2000 Spider: after 26 years between Spiders.
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