Taking over somone else's project

mikestang63 said:

you are going to have to do a lot of diagnostics..
Did the PO convert to a manual brake setup?
what brakes are on their- rotors, calipers, booster, MC

If the booster was bad the pedal would sink to the floor and not come back up when you start the car with your foot on the pedal
with the car off, put your foot on the brake and hold it, it should NOT go down
when you start the car it should go down and then rebound when you take your foot off

Do you hear any hissing when you depress the pedal

did you check the following
check valve on the booster
line from the booster to the Vacuum tree.

Post pictures as those help

That is why I hate buying modified/hacked up cars and prefer to get them as stock as possible and build them the way I want

Click to expand...

90sickfox said:

To check the valve take it off and blow through both ends. Its a flapper valve so air should only flow through one end.

Pics would really help.

Click to expand...

Purplenotch27 said:

Looks like it's the stock master and booster with gt v6 brakes. So I'm guessing I need the booster and master for a better pedal feel and brakes I don't need to put my foot through the floor to stop.

Click to expand...

a91what said:

Which MS system did you go with? who did the tuning?

Click to expand...

a91what said:

cool, are you leaving the car with them?

Click to expand...

Mustang5L5 said:

So looks like you have 94-98 GT/V6 brakes front and rear, but running the stock MC and booster.

That pedal combo should be extremely soft, not hard like you are experiencing. Judging from the looks of the brakes, and lack of contact on that rear rotor, I would make a guess that one or more of the caliper pistons are seized and that's why the pedal is so hard.

It's not the correct MC/Booster combo anyway for the brake setup. You should be running a 94-95 GT 1 1/16" bore master cylinder and a 1993 Cobra booster. However, I think your brakes have other issues going on, and what I mean by that is seized calipers or slide pins or possibly no vacuum at all at the booster.

Engine off, pump the pedal until it's rock hard. Start the engine, and the pedal should sink once vacuum begins to pull from the booster. That braided vac line to the tree is interesting, but it probably is leak free. It's not uncommon for a MC to leak out the back into the booster and destroy the diaphragm giving you a huge leak.

I'm banking on seized calipers though. Jack the rear end up to get both wheels off the ground. STart engine and get the rear wheels spinning and lightly apply the brake. Can you stop the rear wheels easily?

Click to expand...