Rear wheel cylinder dimensions

[gzink]

Anyone know the rear wheel cylinder dimensions- diamater of piston, etc.?

 

[jfriese]

Speaking of brake cylinder pistons, does anyone have any ideas about having pistons made from some material that doesn't degrade when water gets in? Perhaps stainless steel.

John Friese
67 White
67 Red

 

[CapnJohn]

Anyone know the rear wheel cylinder dimensions- diamater of piston, etc.?

As I recall;

• Front - 20mm
• Rear - 22mm
• Master 22mm

 

[PeterP]

Speaking of brake cylinder pistons, does anyone have any ideas about having pistons made from some material that doesn't degrade when water gets in? Perhaps stainless steel.

It seems like a lot of people manufacture stainless pistons for disc brake calipers. I'm not sure what the actual piston looks like for our brakes, but it can't be that much different. You would probably want to find a mechanical engineer to make sure there are no clearance issues due to the different rates of expansion of stainless and cast iron, but that's just a guess.

 

[jfriese]

Peter,

Disc brake pistons are quite shallow and wide while the Amphicar pistons are relatively rather long so twisting and binding isn't a problem. Expansion characteristics of different materials shouldn't make much difference since, unlike the engine pistons, the tolerances are quite sloppy. I'm currently having stainless steel pistons machined for my Amphicars which should eliminate the corrosion issues with the pot metal that the original pistons are made of. I told the machine shop to make me enough pistons for 4 cars and to keep the program in his CNC machine, so there might be more of these to be had in the future.

John Friese
67 White
67 Red

 

[Dale B]

Hi John,

What is the cost to get the machining done? If we had a larger quantity would the price go down? I might be interested in getting some if the price is reasonable.

Thanks,

Dale B
MI

 

[jfriese]

Hi Dale,

I don't know yet but should have an idea in a few days. I'll let you know.

John Friese