71stang99

I switched m 4 wheel manual drum over to complete factory power front discs some time ago. The system worked flawlessly.

Recently I installed MPB rear brake kit and bled the brake (so I thought) Any tips on setting the calipers initially or the parking brake? These are GM calipers so to keep the rears adjusted correctly the parking brake has to be set everytime. The instructions were followed but the pedal does not feel right and I have no brakes. The instructions also state that if the rear brakes lock up then a proportioning valve would be needed. I ran out of time to work on it till Friday so any help is appreciated. Any thoughts?

MustangBradley

A proportioning valve is a cheap and easy way to get your brakes to act like you want them to. I suggest installing one.

Did the rear kit come with a new master cylinder? If so, did you bench bleed it? This important step is often overlooked.

From your description, I would guess you still have air in the system. But a prop valve will help.

http://mustangefiswap.blogspot.com/

2+2GT

NO brakes at all? Does the pedal go to the floor?

71stang99

no brakes (yes to the floor), I was in a hurry when I bled them and figured it was air in the lines or the proportional valve or both. The MC was installed when the entire front brakes were installed last year.

The only lines that should need bleeding would be the rear right? as the two systems are independent?

thanks

JMD

Your issue is probably air in the lines or in the top of the caliper, if the calipers have bleeders at the top and bottom, (like wilwoods) you need to make sure to bleed the top bleeders.

If the bleeders are not the issue, there is likely an air bubble in the line that is messing with you. you might want to try to gravity bleed.

Get a good pedal, then determine if you need a prop valve.

Having NO brakes (no brakes front or rear? On my first read of your post I had assumed no rear brakes only,,, but if NO brakes the following applies!) seems to almost GUARANTEE air in the lines. (OR a total master cylinder failure, which is very, very, unlikely).

JMD

You need to bleed ALL of your brakes, starting at the RIGHT REAR, then the LEFT REAR, RIGHT FRONT and FINALLY the LEFT FRONT.

I might assume that you only opened the rear system to install the calipers, but this does not explain your total lack of pedal. Bleed them all to be sure of what is going down here.

Make sure your M/C does not go dry when bleeding, and gravity bleeding is just bitchin when you have the time and it works...

71stang99

I bled the brakes rear and the fronts along with the master cylinder which was done first. The baking is just not there, the pedal still goes to the floor with a touch more braking then before which is not saying anything. The dash brake light now does not stay illuminated like before. If I pump the pedal I do get a little feel, Is it time for an aftermarket proportioning valve? will that allow the pressure to be set correct? If so which is the best for my application? (factory power disc/master power brake rear) Thanks.

blue66mustang

Are the rear brakes adjusted correctly ? They go a long way towards setting pedal height.

71stang99

I adjusted them or so I thought correctly. The instruction state to turn the adjuster nut until a slight drag is felt on the rotor. The instructions bounce around and are vague at times, you do the first part and then the last tow pages are conflicting steps to adjust the rear brakes using the adjusting nut a some hoohicky about setting the parking brake 60 times.

blue66mustang

Let me ask you this. Did the kit come with a in line residual valve? I belive you need one for rear disc. This keeps something like 10 pounds of pressure on the pistons so they dont recede into the bores of the calipers.