Author Topic: 1979 Brake booster  (Read 272 times)

JohnnyD

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1979 Brake booster
« on: October 15, 2017, 09:31:16 PM »
Alright Guys,,,,,,,,,,this is going to sound stupid but I am having a brake issue with rear calipers locking up.  I have changed all the hard lines and the flex line from the rearend to the body, changed the calipers, pads and rotors in the rear because they were just TOAST and every time I think the problem is corrected, those rear calipers lock up again. 

Now in looking at the booster, master cylinder and P-valve, I seem to have one that is commonly seen on 3rd gens and not the pancake style booster on the second gens. I have the 403 engine but does the 400 have a different brake booster assy??? So ,,,,,,,,,WHAT is the correct booster assy for the 79 Trans Am with WS6 package, 403ci.  Really getting tired of this brake issue

Thanks
Johnny
« Last Edit: October 15, 2017, 09:35:20 PM by JohnnyD »

Brashanic_IM

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Re: 1979 Brake booster
« Reply #1 on: October 15, 2017, 11:24:45 PM »
There is a right and left rear caliper. If they are on the wrong side they will get tighter every time you apply the brake

Look at the end of the stud for the brake cable bracket. It will say R or L

I hooked it up backwards once. 
1979 W72 WS6 true barn find survivor

Grand73Am

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Re: 1979 Brake booster
« Reply #2 on: October 16, 2017, 08:20:52 AM »
That's an interesting possibility that Brashanic mentioned. The rear calipers have the same body, so they could be put on the wrong sides. But the screws are different for right and left, and as he said, the exposed end of the screw is marked either R or L. So, I'd check to be sure they're on the correct sides.

Sounds like you have the right booster. The engine doesn't matter. The disc/disc setup uses a different booster from the common disc/drum "pancake" style booster. The disc/disc is called a dual-diaphram booster and looks like below. The combination(prop) valve is different too:

brake booster b by grand73am, on Flickr
Steve F.

olds403

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Re: 1979 Brake booster
« Reply #3 on: October 17, 2017, 07:51:40 PM »
I think I recognize that photo :)

Grand73Am

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Re: 1979 Brake booster
« Reply #4 on: October 17, 2017, 10:49:16 PM »
I think I recognize that photo :)

 :) I forgot where I got it.
Steve F.

Re: 1979 Brake booster
« Reply #4 on: October 17, 2017, 10:49:16 PM »

olds403

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Re: 1979 Brake booster
« Reply #5 on: October 19, 2017, 07:25:31 PM »
I still have it.  Beautiful piece.  Still in box.  Show car quality.    Not going to use it.  All cars are hydroboost and 10th Anniversary will not be 100 pt car. 

Re: 1979 Brake booster
« Reply #5 on: October 19, 2017, 07:25:31 PM »
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