Corroded caliper piston

[monkey64]

Hi,

My 2009 Jazz failed the MOT because the nearside rear wheel was binding.  Quoted me upto £469 to replace rear pads and the caliper if they couldn't free it up.  I don't have a spare £400 right now so I took it away with the view of fixing it myself.  I stripped the caliper down and found the piston is quite pitted (see photo).  I could clean it up but I think it would leak.  BTW: The car has done 110k and these are the original calipers.

My options:

1. Replace the whole caliper (should I replace the pair?).  I can't stretch to a new HEW honda one so I'd be looking at eBay/budget.  Has anyone had any experiences with eBay/budget calipers?  I don't want a whole load more problems

2. Buy a caliper service kit and rebuild it myself.  Problem sure is that I can't be sure that the bore of the caliper is in good shape.  The piston was quite corroded.

I'm not sure which way to go really.  Any ideas?

Thanks

[Brakballe]

Done this a few times so a service kit with piston should do the job since it's the main seal vs piston that is the sealing part, not the cylinder in the caliper.
But: I guess the other side isn't far behind so better buy two sets.

[olduser1]

1st re check the caliper itself what does is the condition of the walls any signs of wear rust I would doubt it, if ok then have a word with Biggred .co.uk they are helpful and have been supplying brakes parts for years. As other forum members suggest get a kit for your car .
Not a bad job now the weather's warming.

[GBH]

Agree with both the above posters. Providing the caliper bores are not too far gone then rebuild kits with replacement pistons (do both sides to avoid having to do much of the work again later - such as waiting for a dry day, jacking up and crawling underneath, bleeding the whole system etc.).

The cause of the corroded pistons is moisture in the brake fluid and is why the fluid should be replaced every few years. This is also to avoid brake failure, where the heat of continous braking builds up and the moisture in the fluid boils and becomes a gas and then compresses and you "run out of brake pedal" and it hits the floor.

I believe BiggRed (as mentioned above) supply rebuilt calipers and if they can that would be the way to go if you don't fancy rebuilding yours, although they do appear to stock a wide variety of various rebuild kits.

[embee]

As said by others,  a new piston and seals stand a good chance of fixing it. Make sure the seal groove is clean and free of crud. Use red rubber grease to assemble things,  not brake fluid (it absorbs moisture and tends to lead to more corrosion).
I recently got some caliper rebuild kits for a different car from  frentech (they seem to retail through an ebay shop). Parts seem to be excellent quality.

[Brakballe]

I forgot to add this golden quote: "The cause of the corroded pistons is moisture in the brake fluid and is why the fluid should be replaced every few years. This is also to avoid brake failure, where the heat of continous braking builds up and the moisture in the fluid boils and becomes a gas and then compresses and you "run out of brake pedal" and it hits the floor."

I replace every 4'th year and never see any piston corrosion.

[monkey64]

Thanks to everyone for their help.

I punched my car details into Bigg Red and it gave me a suitable kit, which I bought.  The pistons from the car measure 30.2mm diameter but Bigg Red has their https://www.ebay.co.uk/itm/282909992330 replacement listed as 30mm diameter.  Difficult to know whether it's going to fit...

[olduser1]

If in doubt give them a ring , I had cause to double check a UK assembled Jazz turns out it was fitted with S2000 front caliped.