Brakes Front brakes heating up, pressurizing fluid, pedal stays up

Mustang5L5

i'm familiar with penetration
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Id prob get the cardone 5473207. That booster doesn't look great and while you are here i'd change it out.


Also, that PV does not look good inside. Iwouldn't be surprised if that rust clogged one of the ports.
 
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Mustang5L5

i'm familiar with penetration
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Wait til you go under the dash to unbolt the booster! Then you'll see what's fun.



Actually, best way to do it is a LONG extension. All the nuts have a straight shot from where you knees would be located with a 24-36" long extension. You might need to remove the lower dash trim, but from there you should be able to see the straight shot to the nuts. Ford designed the pedal assembly so that nothing really blocks them when you come in with an extension.

I made the mistake of trying to go under there with a short rachet and wrench the first time. Wow
 

General karthief

wonder how much it would cost to ship you a pair
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Yeah, the under dash stuff is not fun, pulling the front seat will help tremendously, and those seat studs will poke at you worse than an ex living next door.
I got the cordone booster for the valdez but I had to paint it.
It's a straight shot with a long extension. I had to put a dab of rtv to hold the nut in the socket, kept falling off.
 

MRaburn

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OK, update fellas.

1. Booster is in with new M/C. however it looks like the rod for this booster has a bigger surface area than teh old, so the brake light switch stays on, am I needing a different year brake light?

2. This proportioning valve is crap. Can't get one of the plungers out and its so corroded in there I hate to even try to clean it and rebuild. Source for just getting a new PV?

Thanks
Mike
 

Mustang5L5

i'm familiar with penetration
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You shouldn’t need a new rod. Those brake light switches can be very picky about how they sit on the pedal arm. But could always be production variances.

Prop valve is only available used. You’ll need one from an ~80 thru 86.

I’m not sure if the 87-93 one can be used. I know the top two ports are 3/8-24 and 7/16-24 inverted flare. I can find out the bottom two shortly

edit: looks like the bottom two ports are also 3/8 and 7/16
 
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Noobz347

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2. This proportioning valve is crap. Can't get one of the plungers out and its so corroded in there I hate to even try to clean it and rebuild. Source for just getting a new PV?


Is it this one?


1609372720529.png


Even if I ever did the differences straight in my head it would have been for like 5 minutes.
 

Mustang5L5

i'm familiar with penetration
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Feb 18, 2001
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Is it this one?


1609372720529.png


Even if I ever did the differences straight in my head it would have been for like 5 minutes.

actually, of those port sizes are correct and 87-93 valve would work. You would just need to take the 3/8-24 fitting off the rear of the valve and swap it over to the 87+ valve.

you would lose the brake pressure switch though
 

Habu135

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Regarding the brake light switch, I used two zip ties to hold the switch at the right angle. One was wrapped around the switch and the second one ran through the first and then through the linkage. The angle stayed horizontal enough where when first applying pedal pressure the lights activated.
 

MRaburn

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OK, back to scratch. I had to get my machinist friend to remove one of the pistons (one without the spring) by drilling a small hole and using a screw to pull it out it was so corroded. So today I was going to reassemble. Upon trying to put one of the end caps on, I guess one of the threads either on the nut or the inside of the PV was off and it ate itself up, so both are now missing threads. I will order an old one off of eBay me thinks at this time and rebuild it using both for parts. If it's not one thing its the other with these projects!

Mike