PM brake seals leaking!

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Jan 4, 2025 | 08:32 AM

81shovelhd!

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From: Florida

PM brake seals leaking!

The on my 81 shovelhead PM brakes are leaking.
making a greasy mess all over front and rear calipers.
I've had these brakes since at least 1995.
About 8 months ago I removed them, cleaned pistons and thoughtbInwas ok.
them.
There was a little pitting on a oouple of the pistons.
Would you just replace the seals or go totally new?
I'm thinking new calipers but maybe not necessary.
Your thoughts!

Jan 4, 2025 | 08:47 AM

Uncle Larry

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From: Michigan 15 Minutes East Of Hell

If the piston rides on the seals you are in trouble unless the kits come with new pistons ... Good Luck

Last edited by Uncle Larry; Jan 4, 2025 at 12:46 PM.

Jan 4, 2025 | 11:45 AM

chopper_man

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From: Masshole

I've rebuilt many PM calipers, zero issues. I highly recommend getting your seal kits directly from PM, the few aftermarket ones were junk.

Jan 4, 2025 | 11:51 AM

81shovelhd!

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From: Florida

Quote:

Originally Posted by chopper_man

I've rebuilt many PM calipers, zero issues. I highly recommend getting your seal kits directly from PM, the few aftermarket ones were junk.

Tx!
I'll look into that!

Jan 4, 2025 | 12:35 PM

81shovelhd!

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Quote:

Originally Posted by 81shovelhd!

Tx!
I'll look into that!

Does it matter that there is a little pitting on a couple of the pistons?
I polished the sides so they are nice and smooth now.

Jan 4, 2025 | 04:36 PM

Uncle Larry

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From: Michigan 15 Minutes East Of Hell

If the pistons have pits they can allow fluid to bypass ... They deserve close inspection

Jan 4, 2025 | 05:23 PM

81shovelhd!

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From: Florida

Quote:

Originally Posted by Uncle Larry

If the pistons have pits they can allow fluid to bypass ... They deserve close inspection

Ya know......for the money, time and energy Ill spend rebuilding the old ones it might be more prudent to spend the $ on a new pair of calipers.
If I remember, they are sround $360 each or thereabouts.
We'll see.

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Apr 1, 2025 | 03:12 PM

monckywrench

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chopper_man is wise. I'd get the pistons without hesitation.

I resealed many a caliper wrenching multiple brands but if the piston is pitted I replace it or the caliper. It would be interesting to see if PM uses seals (and pistons) matching an existing HD caliper
as tooling up to produce oddball seals would be a pointless waste of money.