Need help with possible Brake problem.

[Gary13]

Hi,

I just replaced the entire braking system with all new rotors, pads, calipers, lines, hoses, speed bleeders, brake booster, and master cylinder. All parts were sourced either NOS or rebuilt "according to SVO specs" from reputable sites like Maximum Motorsports and Stillen who have experience with SVOs, except the brake booster and seals that came from NPD - M-2005-3A, rebuilt E1BZ-2005-B.

My problem is that on the test drives (after bedding the pads) the pedal travel before the brakes start to engage is around 30% and as I hit about the 60% travel mark the brakes will stop the car better than ever. However, the lack of progression in braking power until I am over 50% travel is worrisome. At the end point the car stops incredibly well but it is scary getting to that point. Almost like every stop has to be treated like a panic event.

We have bleed the brakes three times, checked all the lines for air or loose connections, and even tried the old brake booster which resulted in pedal travel to around 70% before the brakes started to grab. I took the car to a local shop yesterday and they could not find anything "wrong" with the installation or setup but agreed they do not think the pedal travel is correct. Idle is normal and according to the manual the vacuum lines appear to be installed correctly. I cannot hear any leaks but considering the noise under the hood I might be missing something.

Any ideas or does this seem normal for the car?

[k98dave]

Sounds like the adjustment on the booster rod end is not right. Did you measure, calculate, and adj the rod end on the brake booster?

See measure and adj steps here: http://www.maximummotorsports.com/co...s/MMBAK-17.pdf

this instruction is part of a MM adapter kit, but the push rod adjustment process is the same for all master cylinders

[Gary13]

Thank you. I will check the adjustment today as I "assumed" it was correct out of the box. I did notice on the first ride this morning that if I pump the brake first then the pedal travel required on the actual stop is cut in half if that makes a difference.

Sounds like the adjustment on the booster rod end is not right. Did you measure, calculate, and adj the rod end on the brake booster?

See measure and adj steps here: http://www.maximummotorsports.com/co...s/MMBAK-17.pdf

this instruction is part of a MM adapter kit, but the push rod adjustment process is the same for all master cylinders

[MikeFleming]

I did notice on the first ride this morning that if I pump the brake first then the pedal travel required on the actual stop is cut in half if that makes a difference.

That's actually common for new caliper seals. Takes them a bit to not over-retract the pistons.

Give it a couple more days to see if the pedal travel lessens - double-pump before the stop until then.

[Mike S]

Did you bench bleed the master cylinder? You don't specify that above.

Also, my Haynes manual says you have to pump the pedal some 30 times to seat the rear calipers after installing new pads.

[TheSVOTrust]

After years of replacing ALL THAT WAS DESCRIBED above , I have added an item to the list !

https://www.musclecarresearch.com/valve-kit-kh-D7DZ

Mark
P.S. Once you have seen the inside of these units you will rebuild all of your cars !

[Gary13]

Did you bench bleed the master cylinder? You don't specify that above.

Also, my Haynes manual says you have to pump the pedal some 30 times to seat the rear calipers after installing new pads.

Yes, we bench bled the master cylinder once and then the full brake lines three times. I had the new brake booster tested this afternoon and it is to spec. I will try the pedal pump as suggested until the caliper seals seat. Thanks to everyone for the assistance. Now on to replacing the AC Compressor and oil pump in the morning.

[MikeFleming]

Sounds like you have your SVO Task List pretty full.

Keep us posted on the brake issue.

[Gary13]

Sounds like you have your SVO Task List pretty full.

Keep us posted on the brake issue.

The list is quite full. Dropped a built 8.8 in the car, all new springs, struts, shocks, bushings, control arms, steering rack, new T5, cooling system, rebuilt head, VAM and another two dozen or so items ranging from coat hanger hooks to new door/window seals.

We had to adjust the booster rod end this morning as it was off, but until I get the car on the ground I will not have an answer to the brakes. But I think between the rod adjustment and properly seating the caliper seals that I should be fine as there is nothing else left to replace. A couple of pics from the bay I rented at a local shop.

svolift.jpgsvorear.jpg

[TheSVOTrust]

Hay let us know your TOTAL INVESTMENT would you? We know playing with cars isn't cheap -looks like you are a good candidate for a garage -or more cars !

Mark

[Gary13]

Hay let us know your TOTAL INVESTMENT would you? We know playing with cars isn't cheap -looks like you are a good candidate for a garage -or more cars !

Mark

I have way more in the car right now than it is worth. Is it worth it? Absolutely! I will update my cost later on. I am still no where near what I put into my '68 GT500 so that is about the only positive when explaining to the wife why another FedEx box arrived today.

[MikeFleming]

Looks good!

Carry On!

[TheSVOTrust]

I have way more in the car right now than it is worth. Is it worth it? Absolutely! I will update my cost later on. I am still no where near what I put into my '68 GT500 so that is about the only positive when explaining to the wife why another FedEx box arrived today.

Haha You aren't going to get an sympathy from me ! (us) We all have so many cars that - finding another that is infected with the disease isn't a bad thing. I look at it like I just found someone else I can tell my wife I "traded a car to" - so I don't have to sell one !

Mark

P.S. You would be surprised how many FE owners also have SVO's !

[stott]

how hard were the window seals?

did you just do the run channels or the inner and outer door belt strips as well?

thx

[Gary13]

how hard were the window seals?

did you just do the run channels or the inner and outer door belt strips as well?

thx

I replaced the channels along with the inner and outer door belt strips.It was not simple due to the time involved but not really that hard either on the labor side. I have to admit I cheated by reviewing a video over at LMR that described the process step by step. It takes a bit of an effort to close the doors now but the car is actually quiet to some degree, the power windows work like new and no more water inside when washing the car. I am doing the hatch next as I need to replace the seal, bumpers, struts, and striker along with the speaker panels. The hatch is slightly off center also but it does not appear I can adjust the hinges any further so that will require a body shop. Getting off topic here since this is the brake, wheels, and tire forum.

So, on the brakes I will not know until Tuesday or so as the AC Compressor that was ordered is now delayed along with the center rear brake hose I wanted in SS and not rubber. My "creative engineering" modification for the 7.5 specific SS line is not going to work under full suspension load so I ordered a later GT line to replace it. Also, as much as I liked the new BFG Rivals on dry pavement, any standing water causes a real issue with those tires. So I am switching over to the Bridgestone RE11As, might give up a tad in the dry but any wet spots will no longer create a pucker moment in the car.

Thanks to Jack at MM, got the rear suspension working right and will add the panhard setup later today.

svorearB.jpg

[stockman1]

nice work Gary. Great color too!

[Bob Holmes]

Did Jack say that a Panhard works with a quadra-bind and a quad shock setup? Wouldn't that cause bind?

[stott]

Did Jack say that a Panhard works with a quadra-bind and a quad shock setup? Wouldn't that cause bind?

There shouldn't be bind issues with just a panhard arm, it just turns a 4-link into a 5-link. It's the torque arm that will bind the 4-link setup, as it actually makes it a 3-link

[Gary13]

Did Jack say that a Panhard works with a quadra-bind and a quad shock setup? Wouldn't that cause bind?

It was suggested to keep the quads on the car since they help to control rotational movement while the panhard bar controls right to left movement. I have driven another SVO with the same recommended setup without an issue and in fact it was superb in the twisties considering the age of our car. The biggest concern was ensuring that I used the HD upper control arms with the slightly stiffer rubber bushings along with the same upgraded rubber bushings on the axle/differential side instead of urethane or delrin as that would create a binding nightmare.

That said Jack highly recommended going to a coil-over setup and a couple of other changes like a SN95 steering rack/front brakes/more, which I have done on my other mustangs but after doing a T5 replacement I just could not write that check. Considering this car might be driven 1500 miles a year and I know with the new setup I can finally outrun a couple of pesky Minis and Miatas in my group then I will be happy with this setup (well for now).

[Gary13]

Good news - Between the brake booster rod adjustment and bedding in the calipers the brakes work like new, if not a little better. Found a drop in replacement AC compressor and now have ice cold air so I can pay attention to bedding the pads now.
Bad news - Severe condensation inside the right headlight now, between the heat and humidity today it looks like the headlight is taking a shower. Get one issue fixed and another one pops up.