Brake Piston

Maintenance advice to keep your Spider in shape.
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statmasterack

Brake Piston

Post by statmasterack »

Evening everyone,

Quick question about rebuilding the brake caliper ... 1977 Fiat Spider, sticky left-front brake, so while I was working on the hub, I figured I would clean the brake caliper, replace seals, etc. I was able to get the piston out by pumping the brake pedal without too much difficulty. My question is -- at what point should I replace the piston / caliper block, etc? There's some mild rusting/pitting on the piston in-between the oil seal and the dust cover (after cleaning it real well with brake cleaner):

Image

and

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I'm a very much less-than experienced mechanic, so apologies if the question is noobish. The piston housing looks to be in reasonable shape. I haven't been able to pull it off yet, as I stripped that bolt on the metal brake line, and ultimately ended up ripping the metal brake line trying to break those bolts free. Lots of other good posts on the forums about that that I've been reading through ;).

Thanks!
tglancy

Re: Brake Piston

Post by tglancy »

First if there is pitting of the piston it likely time to change the calipers as a kit. Very small pitting or rust could be polished out but it would be easier to replace them.

Hard lines will require a patch at this point. You will need flaring tools and a tube bender etc. Now that you are this deep you should also change any flexible lines, maybe new pads, new rotors. Once you start …..
So Cal Mark

Re: Brake Piston

Post by So Cal Mark »

I would replace that piston unless you just can't get another.
statmasterack

Re: Brake Piston

Post by statmasterack »

Hey guys, thanks for the replies. I'm going to go ahead and replace ... we'll see how that goes.

Cheers!
statmasterack

Re: Brake Piston

Post by statmasterack »

Speaking of flaring tools -- in haste I bought a flaring tool from Autozone yesterday, spent some time playing around with copper tubing (for practice). I had read somewhere that a single flare was what was needed (as opposed to doing the second step to get the double flare). The more I looked at the result, compared to the flare on the original line, the more I thought, not so much. Am I correct in assuming that I'm going to need a DIN ("bubble") flaring tool for doing these lines, as opposed to the SAE ("double") flare? Reference the pictures at the top of this page: http://www.fedhillusa.com/.

Also, any thoughts on the Cunifer tubing over steel?

Regards,
Darryl
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