Brake Lubricant

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John Vardanian
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Brake Lubricant

Post by John Vardanian » Thu Feb 07, 2013 1:37 am

Any advice on a type of lubricant to use for assembly?

As part of the diff removal I honed the four wheel cylinders in the rear and during reassembly used Raybestos assembly lubricant. My rear brakes now stick, the pistons do not retract. No, it's not trapped hydraulic pressure. I am thinking that the lubricant might have something to do with it. Does anyone have any experience wit this? Thanks.

http://www.summitracing.com/parts/agb-baf12

john
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tyang
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Re: Brake Lubricant

Post by tyang » Thu Feb 07, 2013 7:21 am

HI John,

There used to be a red grease from Lucas that you would used to install the brake seals, but I don't know if it's easy to get this stuff. Richard Garre gave a jar of grease that I've been using with pretty good results. He should be able to ring in and tell you who makes it.

Good luck.

Tom
'63 330 America #5053

8339
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Re: Brake Lubricant

Post by 8339 » Thu Feb 07, 2013 8:40 am

Gentlemen, the product I use that I also gave to Tom is PBR Rubber Grease. As an assembly lube on hydraulic internals the grease performs vey well, will not interfere with brake fluids. You can purchase through Amazon or www.HRPworld.com, or some the racing parts outfits.

Good Luck
Richard Garre
Radcliffe Motorcar Co.

airsanford
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Re: Brake Lubricant

Post by airsanford » Fri Feb 08, 2013 1:18 pm

I've always used Dow Corning DC-4. Available at Aircraft Spruce, among others.

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John Vardanian
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Re: Brake Lubricant

Post by John Vardanian » Sat Feb 09, 2013 2:22 am

I remember once flushing the brake system of a car I had just gotten with DOT-4 brake fluid. The next time I went to drive it the brakes stuck. I hadn't realized that the car had silicon fluid in it before flushing.

Pardon my ignorance, but won't silicon based lubricants be incompatible with DOT-4? Thanks.

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Re: Brake Lubricant

Post by 8339 » Sat Feb 09, 2013 10:05 am

You cannot mix DOT-4 with silicone brake fluid, regardless of what manufacturers and "internet experts" say. Most replacement brake hydraulic seals use EPDM rubber products I believe, which are not compatable with silicone brake fluid as well. John you will probably have to dis-assemble all the brake hydraulic components, flush them with denatured alcohol and re-assemble. Hopefully you'll be able to save all the rubber seals. I've been through this in the past when silicone brake fluid was all the rage and it will cause you much pain if you don't correct it. Don't confuse DOT 5 with DOT 5.1, 5.1 is a "regular" style brake fluid with a higher temperature rating as opposed to DOT 5 which is silicone. Keep in mind most all brake fluid is now synthetic but not silicone.

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John Vardanian
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Re: Brake Lubricant

Post by John Vardanian » Sat Feb 09, 2013 2:45 pm

Thanks, I guess my point is this, is using a silicon based lubricant in a system that is operating with DOT-4 okay?

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Re: Brake Lubricant

Post by 8339 » Sat Feb 09, 2013 6:25 pm

John, my fault for reading your thread carefully. I still would not mix a silicone based lubricant with DOT 4, just my opinion of course. I've not had a problem with the PBR Rubber lube in past years.

airsanford
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Re: Brake Lubricant

Post by airsanford » Sun Feb 10, 2013 10:45 am

I first learned of silicone grease when I worked for a BMW dealer several lifetimes ago. The factory ATE brake lubricant is silicone grease. The DC-4 is the same stuff. The trick is not to use much; just a little dab wiped on the seals is sufficient. I've rebuilt hundreds of hydraulic components, never had a problem.

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Re: Brake Lubricant

Post by motob » Sun Feb 10, 2013 10:06 pm

I used to use the red lucas rubber grease to assemble rubber brake components. While is worked very well on brake caliper and wheel cylinder seals, it was so thick that it tended to cause the pistons in brake and clutch master cylinders to stick, especially if they sat for some time before being installed on the car and filled with brake fluid.

I now use Raybestos BAF12 brake assembly fluid and it works great. It is easy to buy, in fact you can order it on Amazon.com:
http://www.amazon.com/Raybestos-BAF12-B ... B001ANJ2GE

Brian Brown
Patrick Ottis Co.

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John Vardanian
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Re: Brake Lubricant

Post by John Vardanian » Mon Feb 11, 2013 1:18 am

Hi Brian, your Amazon link doesn't work. Is this the stuff you are referring to?

http://www.tomyang.net/cars/ferrari.html

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Yale
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Re: Brake Lubricant

Post by Yale » Mon Feb 11, 2013 1:46 pm

Tom's site is not set up so that you can link to anything mentioned in it you just get the front page of the site with all links.
1964 330GT #6097

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John Vardanian
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Re: Brake Lubricant

Post by John Vardanian » Tue Feb 26, 2013 1:08 am

So, you take things apart and put them back together and after a while you get disillusioned, you think you know your stuff. Then it takes something like this to make you realize you don’t know shit. Read the first post of this thread (by yours truly) and you'll get the joke.

The brakes were having a hard time retracting because these nuts need to be finger tightened, then backed off a tooth or two to let the cotter pin in. I obviously had them too tight. Mind you, in my defense, there are spacer bushings that “in theory” should make the shoes indifferent to the tightness of the nut.

john

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250GT
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Re: Brake Lubricant

Post by 250GT » Wed Feb 27, 2013 9:10 am

John,John,John,
First : If my observation is right you made a HUGE mistake in building it back together.
This also explain the destroyed dohnut too.
and leaks.
When you remove the outside drumm this comes off together off with the 42 Hub !
Your`e last picture shows the hub fixated to the basis plate the crown nut with cotton pin is clearly visible.
you´re wheels cannot be turned at ALL freely.
Secound: You´re shoes look like self made or replaced these are normally out of alu too
Third: The linings are not segmented normally.

A pic of mine after rebiuld without outsidedrumm- without hub of course- you look directly on the single lip seal.
If this is all true you can be happy not blowup the hole rearaxle housing and more.
see the diff. of both pics.
but never too late to correct

C.
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250GT
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Re: Brake Lubricant

Post by 250GT » Wed Feb 27, 2013 9:32 am

Concerning this :


"The brakes were having a hard time retracting because these nuts need to be finger tightened, then backed off a tooth or two to let the cotter pin in. I obviously had them too tight. Mind you, in my defense, there are spacer bushings that “in theory” should make the shoes indifferent to the tightness of the nut."

The shoe movement can be easily checked by the lever of the handbrake moving outside/ lateral of the shoes
this is not an" fixation nut point" but "guiding nut point".

C.

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