Pitted Stainless Steel Brake Pistons - or Plated?

[gus]

Oh, and they should be 303, 304, or 316 grade stainless. 316 is most corrosion resistant but is truly overkill

[david.g.chapman]

I have finished my calipers - just thought I would show you all. I used POR15 tank seal paint to finish the calipers off. This paint was left over from when I did my fuel tank 10 years ago. POR15 say that you should throw the excess paint away when finished, but I am not like that I suppose it must be a US litigation thing so they have to say dispose of it.

The paint is good for 450 degrees F for a few hours exposure - that's good enough for me. The paint dries like glass and shrugs off brake fluid and petrol (of course).

I also attach a slightly blurred pic of the old piston i filed. You can see the rusty patch and the remains of the black pit in the middle. I have since learned that these pistons were forged and then plated in what looks like stainless steel.

Cheers,

Dave Chapman.

[terryp]

I seem to always have a problem with the small area of piston that is after the seal and under the dust rubber.
My Caterham brakes began to bind again and sure enough , it's this bit again. My Pistons were Zinc plated.
Has anyone found a good supplier of the correct grade stainless steel Pistons?

Thanks
Terry

[david.g.chapman]

Hi Terry,

My rear pistons came from Classicar Automotive at ?16.99 each ex VAT and delivery. They are described as stainless steel.

The front pistons came from BiggRed via Ebay and included the seal kit. They were ?67.50 including VAT and delivery, and were described as stainless steel as well. I am not too fussed about the grade.

Note that I ordered the front piston set under Triumph TR5/TR6/GT6 pistons, to fit a 16PB caliper. The boots for this type use a wire retaining ring. You can check your caliper type as it should be cast into the caliper somewhere.

Classicar Automotive will have some stainless steel front pistons in about 3 weeks if you prefer to order from them.

Dave.

[terryp]

Thanks Dave for the information

All the best
Terry

[Sea Ranch]

Wondering . . . as my calipers are now off the car . . . how many are splitting the calipers open during a rebuild, or leaving them bolted together.

Suppose it depends on what the bores look like after the pistons are removed . . . ?

Thanks,

Randy