Author Topic: Question about using an aluminum master cylinder  (Read 1241 times)

Offline KillerBee

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Question about using an aluminum master cylinder
« on: April 21, 2017 - 09:13:02 AM »
Working on the brake system on the wife's 1971 R/T Challenger.

Converting from manual 11" 4 wheel drums to manual front disc/rear drums and replacing everything front to back.
 
I bought the recommended aluminum master cylinder from Dr. Diff with the adaptor plate and distribution block.
Converting to these aluminum master cylinders is new to me so I got some questions.

I noticed some aluminum master cylinders have a dust boot for the push rod, mind did not come with one,
Do I need one?
Where can I buy one?
How is it installed?

I've been told I can use the original manual brake push rod?
I installed the included grommet in the back of the master cylinder, is there any special way the push rod needs installed?

Thanks.




Offline burdar

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Re: Question about using an aluminum master cylinder
« Reply #1 on: April 21, 2017 - 09:32:13 AM »
Not sure about the dust boot.  Manual brake masters use a dust boot...and there are dust boots on the back of brake boosters.  I've never thought about what people do when using an aluminum master without a booster.  I'm going to be in the same situation so I'm curious as to what other say.  We don't use these cars as daily drivers anymore and we keep them in much better shape.  Maybe a boot isn't needed.

As far as the pushrod.  I can confirm that the stock pushrod will work.  I measured the distance from the mounting surface to the inside of the piston on my stock master cylinder.  Then I measured the distance from the mounting surface of the adapter plate to the inside of the piston on the new aluminum master.  Both measured the same.  I'm not sure if you're supposed to install the grommet in the master first or install it on the pushrod first.  Either way, the original pushrod will work just fine.

Offline mopar jack

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Re: Question about using an aluminum master cylinder
« Reply #2 on: April 21, 2017 - 10:04:08 AM »
You will have to push the rod in hard enough to engage it in the grommet so that it looks in and won't pull out.

Offline KillerBee

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Re: Question about using an aluminum master cylinder
« Reply #3 on: April 21, 2017 - 01:37:04 PM »
Thanks guys.

The MP master cylinder kit shows a dust boot.
http://www.jegs.com/i/Mopar-Performance/312/P5249315K/10002/-1

Jegs sells a dust boot that looks the same but I'm not sure if will fit with the adaptor plate.
http://www.jegs.com/i/JEGS-Performance-Products/555/631410/10002/-1

Would it be best to install the push rod into the back of the master cylinder first before installing the master cylinder to the reinforcement plate?
« Last Edit: April 21, 2017 - 01:42:20 PM by KillerBee »