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Disc brake piston seals

BJ8Healeys

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Hi, Spridgeteers!

I noticed while checking the condition of the front wheel bearings ('73 Midget) that there was a greasy mixture of dirt and oil on both disc brake calipers and on the pads. I've cleaned all that up and have new caliper pistons seals and new pads.
The bag o' parts from Moss Motors (P/N 182-840) comes without any instructions. The inner and outer seals are different (one is the seal for brake fluid and the other is a dust seal), but I found that they were installed differently for each piston on the first caliper I'm working on.

One seal is sort of "U" or "V" shaped in cross section with two lips, and the other is a solid square. Anyone know which type is the inner seal? The parts manual doesn't provide enough of a detailed drawing to determine which is which.

Thanks!
 
28 views and no responses yet. Never mind. I did enough research into hydraulic seals on the internet to conclude that the "V" cross section seals are the brake fluid seals for the caliper piston (the ones that are deeper into the cylinder), and the square cross section seals are the dust "wipers" at the top of the cylinder.
 
You are in a hurry Post at 1:30PM and no answers by next morning.
The inner seal is square. The outter seal fits into the metal ring and then is tapped into the caliper.
The inner seal is square to retract the piston a micrometer after you have released the brakes and take the pressure off the pads
 
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