Author Topic: do i put high-vacuum grease in master cylinder?  (Read 1306 times)

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Offline crowned

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do i put high-vacuum grease in master cylinder?
« on: October 12, 2008, 01:10:00 PM »
So, just rebuilt my front brake caliper, and now i'm doing the master cylinder.

i read a lot of threads saying to lube the master cylinder innards with brake fluid before i reassemble it (with new parts, of course), but i'm wondering if i ought to put a smidge of dow corning high vacuum grease on the rubber seals before i reassemble it (a la front caliper).

anyway, if anyone knows, let me know!

thanks.

Offline kghost

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Re: do i put high-vacuum grease in master cylinder?
« Reply #1 on: October 12, 2008, 02:10:34 PM »
No.

Just enough Brake fluid to lube it up.

When its operating the fluid keeps it lubricated.

Obviously theres no fluid in it when assembling....so dab some fluid on it so it doesn't bind up.
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Re: do i put high-vacuum grease in master cylinder?
« Reply #2 on: October 12, 2008, 02:19:43 PM »
+1

Offline crowned

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Re: do i put high-vacuum grease in master cylinder?
« Reply #3 on: October 12, 2008, 02:54:46 PM »
Whoops!  :P  I only put a tiny bit in, in anticipation of this response.  a coating really, not enough to see.  figured it couldn't hurt. hope it couldn't hurt.

Offline kghost

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Re: do i put high-vacuum grease in master cylinder?
« Reply #4 on: October 12, 2008, 03:09:54 PM »
You'll be fine...carry on.... ;)
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Offline TwoTired

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Re: do i put high-vacuum grease in master cylinder?
« Reply #5 on: October 12, 2008, 03:51:24 PM »
Don't be surprised if your brakes feel spongy.  Silicone doesn't mix with anything And it a bit more compressible than Glycol based fluids.

Are you using DOT 5 brake fluid?

None of the high vacuum grease is supposed to be in the brake fluid vessel, either in the master OR the caliper.

The grease is just to keep water off the components between the brake piston and the brake puck.
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