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Hey Everybody!
I have a 1965 Mustang that I’m doing some work to. I bought a Front Disc Brake Conversion from CJPonyParts. Here’s the link


I installed everything correct but I’m a little worried and confused. After bleeding the brakes, bench bleeding the MasterCylinder, and hooking everything up, when I go to press down on the brake it has lots of inches of travel where no pressure it applied to the brake booster - Master Cylinder - or to the brakes. When the brake pedal is severely close to the wall it finally applies pressure to everything and somewhat works.
Does anyone have any ideas of what the problem may be? Is it just suppose to be like this? What do I need to do?

Thanks for any response!
 

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Your situation with installing a power booster conversion kit and having long pedal travel is extremely common. This is discussed on a weekly basis here for years and years. Often it is the result of the adjustment of the booster pushrod to the master cylinder clearance. Next on the order of occurrence is the adjustment of the pedal pushrod. Of course, there's always the possibility of air trapped in the hydraulic system. And then there's the question of whether the parts are even correct despite spending lots of money at a reputable business. And even if everything is correct, something might be defective. Don't forget about residual valves, proportioning valves, and rear brake shoe adjustment. Search is your friend here; Search results for query: long pedal travel
 

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I'm almost thinking that these power brake kits are an extreme dis-service as they are being marketed.
They are right up there at the very top on the scale of successful installation difficulty.

ex-Global West GM
1991-1995
 

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Hey Everybody!
I have a 1965 Mustang that I’m doing some work to. I bought a Front Disc Brake Conversion from CJPonyParts. Here’s the link


I installed everything correct but I’m a little worried and confused. After bleeding the brakes, bench bleeding the MasterCylinder, and hooking everything up, when I go to press down on the brake it has lots of inches of travel where no pressure it applied to the brake booster - Master Cylinder - or to the brakes. When the brake pedal is severely close to the wall it finally applies pressure to everything and somewhat works.
Does anyone have any ideas of what the problem may be? Is it just suppose to be like this? What do I need to do?

Thanks for any response!
Here's where you're at....... general comments-
You need to make sure you have no latent air in both brake circuits. You need to have rear drum (if that's what you have) completely adjusted.
Last but not least, if this were my deal, I'd screw some brake pressure gauges onto each corner and see what's there for pressure.
Without that, we're just guessing about what kind of braking performance you're going to get when everything else is up to snuff.

ex-Global West GM
1991-1995
 
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I'm almost thinking that these power brake kits are an extreme dis-service as they are being marketed.
They are right up there at the very top on the scale of successful installation difficulty.

ex-Global West GM
1991-1995
Man do you have it right!
 

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I think I need to add a bit here.
Yes, there are many systems out there. Most will work. Some will need more of precise direction to install.
Then there are "will fit if" systems that take extra knowledge to get to work. This knowledge has to be supplied by the vendor, a Seller that knows their product.
Call the vendor, they should have a distinct, direct knowledge of the situation you are experiencing.
 

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Hey Everybody!
I have a 1965 Mustang that I’m doing some work to. I bought a Front Disc Brake Conversion from CJPonyParts. Here’s the link


I installed everything correct but I’m a little worried and confused. After bleeding the brakes, bench bleeding the MasterCylinder, and hooking everything up, when I go to press down on the brake it has lots of inches of travel where no pressure it applied to the brake booster - Master Cylinder - or to the brakes. When the brake pedal is severely close to the wall it finally applies pressure to everything and somewhat works.
Does anyone have any ideas of what the problem may be? Is it just suppose to be like this? What do I need to do?

Thanks for any response!
Also if that Proportioning Valve / Combination Valve has a plastic switch on it. This switch should be removed and special tool installed when bleeding brakes. This keeps that valve from moving to the front or rear. Meaning, If that valve moves to the front or rear it will stop any brake function to the front or rear. The valve moves because it sensing a lot brake fluid moving threw the system, From bleeding brakes or a leak in the system.
 

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Also if that Proportioning Valve / Combination Valve has a plastic switch on it. This switch should be removed and special tool installed when bleeding brakes. This keeps that valve from moving to the front or rear. Meaning, If that valve moves to the front or rear it will stop any brake function to the front or rear. The valve moves because it sensing a lot brake fluid moving threw the system, From bleeding brakes or a leak in the system.
Completely untrue that it will "stop any brake function to the front or rear."
Shifting the shuttle because of a leak merely turns on the brake warning light. It doesn't even tell you whether it's the front or rear circuit
that is the issue. The "fail safe" in the system is actually dependent upon the proper operation of the split system, which is courtesy of the
dual reservoir master cylinder.

ex-Global West GM
1991-1995
 

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Completely untrue that it will "stop any brake function to the front or rear."
Shifting the shuttle because of a leak merely turns on the brake warning light. It doesn't even tell you whether it's the front or rear circuit
that is the issue. The "fail safe" in the system is actually dependent upon the proper operation of the split system, which is courtesy of the
dual reservoir master cylinder.

ex-Global West GM
1991-1995
Absolutely a fact in this statement!
 

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I found the info on this on Master power brakes web site. Untrue or not, it happened to me and what a pain in the butt. So when I bleed brakes and it has one of those combination valves, I'm pulling the switch and putting that tool in. Right or Wrong, I would rather safe then sorry.
 

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I found the info on this on Master power brakes web site. Untrue or not, it happened to me and what a pain in the butt. So when I bleed brakes and it has one of those combination valves, I'm pulling the switch and putting that tool in. Right or Wrong, I would rather safe then sorry.
What's "untrue"............. the fact that the shuttle can shift when bleeding the brakes, so you "pin" it with a tool? Sure it can.
Or the "untruth" ............ that the shuttle when shifted will stop any brake function to the front or rear?

The tool's in the photo. I've had mine for years. I agree, you should use it when bleeding brakes. That's what it's for.
I'm hardly a yokel with regard to brakes. I've worked for a brake manufacturer. (the biggest) I've designed and sold brakes. I won't tell you some BS.

By the way, I looked on the Master Power website. Other than possibly shifting the shuttle (and causing the light to illuminate) by not using the tool, nothing
is mentioned in their tool write-up about effecting brake system operation if the shuttle shifted to the front or to the rear. That's because that doesn't happen
if the shuttle shifts.

ex-Global West GM
1991-1995

784509
 

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If schuttle shift on side to other, back and forth, No fluid travel will be effected.
Many misstatements, wrong messages out there.
Locking pin solely dedicated to bleeding the system.
 

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I have CJ's front/rear version of this kit sitting in my shop that I will be installing soon and I've read the manuals front to back. The manuals, while not great at all, does have a section on the pedal travel issue and how to address it. Its likely the booster rod adjustment as others have mentioned.

CJ's gets these kits from MBM -> DBK6473-FD-250 - 1964.5-1966 Ford Mustang Front Power Disc Brake Conversion you can pull up some other resources on their site by the product number.
 

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What's "untrue"............. the fact that the shuttle can shift when bleeding the brakes, so you "pin" it with a tool? Sure it can.
Or the "untruth" ............ that the shuttle when shifted will stop any brake function to the front or rear?

The tool's in the photo. I've had mine for years. I agree, you should use it when bleeding brakes. That's what it's for.
I'm hardly a yokel with regard to brakes. I've worked for a brake manufacturer. (the biggest) I've designed and sold brakes. I won't tell you some BS.

By the way, I looked on the Master Power website. Other than possibly shifting the shuttle (and causing the light to illuminate) by not using the tool, nothing
is mentioned in their tool write-up about effecting brake system operation if the shuttle shifted to the front or to the rear. That's because that doesn't happen
if the shuttle shifts.

ex-Global West GM
1991-1995

View attachment 784509
Maybe this will help, www.mpbrakes.com Go to Tech talk, Then to FAQ's, Scroll down to Valve FAQ and look at " What does it mean when a Combination Valve has tripped?" I'm not trying to start anything with you. Just trying to learn more about this and help.
I agree, There is too much misinformation out there.
 

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Maybe this will help, www.mpbrakes.com Go to Tech talk, Then to FAQ's, Scroll down to Valve FAQ and look at " What does it mean when a Combination Valve has tripped?" I'm not trying to start anything with you. Just trying to learn more about this and help.
I agree, There is too much misinformation out there.
Yeah, I see what it says there-
Referring to the shuttle..."When it moves, or when some people call it "tripped", the internal valve moves and blocks the non-working port allowing a person to get home"
That's not a smart thing to say. Here's the shot right off their website of the cutaway combo valve.....
It's pretty clear that the way the block is machined, moving that brass shuttle isn't going to block the fluid in that circuit.

ex-Global West GM
1991-1995

784595
 
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I've tried a few different power brake setups on my '66, but I finally hit the sweet spot (4-wheel Wilwood disc brakes) when I went to a Wilwood manual 1" MC with an adjustable proportioning valve. I could never get the pedal right and it always felt labored to stop. The manual kit feels just like power brakes, but even better IMO. These guys that are chiming in are an awesome resource.

Tim
 
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