Project Roxy

[Rochlow]

So I bought these big fancy brakes from CPP. In trying to adjust them yesterday, I finally got fluid through the lines. However, I couldn't get the caliper to clamp the rotor in the front or rear. I bench bleed the M/C and had fluild coming out of all four calipers.

I noticed that I have a deep bore M/C that CPP provided in the kit and the booster has an adjustment to accomadate the bore.


However, the pedal still goes to the floor and doesn't stop the rotor from spinning.. I'm stumped on this one..

[knomadd]

You may have already looked at all of this, but I'll try to jog your memory or give some ideas where to look...
Are you sure the pedal is contacting the piston in the master? Sometimes there is a spacer required between the pedal pin and the master cylinder to engage them both. I think this might be your problem. It's possible to have the brakes bleed by gravity alone instead of pedal force.

I assume you're using a vacuum booster, but if you are using hydro boost, make sure you've bled your power steering and don't have low fluid or frothy fluid (lots of air in the system).

Are there any obstructions in your master preventing the fluid from leaving the reservoir? Maybe debris in the lines? Did you replace all of your brake lines or reuse factory stuff?

What kind of proportioning valve do you have? Is it a factory style from these trucks, a newer factory style (typical upgrade in most disc kits), an adjustable valve only to the rears? Air can be trapped in a factory style unit. It's possible to bleed some of them, from what I've heard (never done it myself) but I've had air in my lines because of one of those types. At the time, I didn't have many brake tools so I had to have a mechanic pressure bleed my lines to get the last of the air out.

These last items require the pedal to fully engage the master though, which it doesn't sound like is happening.

[Rochlow]

There is an adjustable pin on the booster that is making contact with the bore on the M/C. and I am using a vacuum booster.

All the products are new, including the lines. I'm using a CPP disc/disc proportioning valve that came with the kit.

I was going to do a gravity bleed and let it sit for a few hours, followed by a mechanical bleed.

[Hart_Rod]

Originally Posted by Rochlow

So I bought these big fancy brakes from CPP. In trying to adjust them yesterday, I finally got fluid through the lines. However, I couldn't get the caliper to clamp the rotor in the front or rear. I bench bleed the M/C and had fluild coming out of all four calipers.

I noticed that I have a deep bore M/C that CPP provided in the kit and the booster has an adjustment to accomadate the bore.


However, the pedal still goes to the floor and doesn't stop the rotor from spinning.. I'm stumped on this one..

Which mastercylinder did you buy?

[Rochlow]

6772FRBK6-BB is the kit from CPP that I bought. It came with a deep bore M/C. However, after reading it appears that deep bore is for manual brakes only and not disc/disc.

[knomadd]

I don't know for sure, but it seems like either you aren't getting full engagement from the pedal to the master or there's still a lot of air in the lines. Even if you booster was bad, you should still have some caliper movement with manual type brakes (just harder since you'd be fighting the booster). The only way I can see the calipers not moving would be due to the pedal and master not engaging completely, too much air in the system, blockage in the lines, or binding in the calipers. Or, the adjustment from the pedal to the booster isn't set correctly (pedal goes to floor before completely engaged with master cylinder).

Maybe I'm missing something, but that's all I can think of. I'll step out now and let someone else chime in.

[Rochlow]

Yea.. I figure it's one of those four issues.. I just have to hunt to find it. I ruled out blockage because I'm getting fluid to the caliper. However, it's not going threw with alot of pressure.

[Hart_Rod]

Originally Posted by Rochlow

6772FRBK6-BB is the kit from CPP that I bought. It came with a deep bore M/C. However, after reading it appears that deep bore is for manual brakes only and not disc/disc.

Did that kit come with a plastic syringe to help get the air out of the mastercylinder?

[Hart_Rod]

Some helpful articles:

http://www.classicperform.com/Instru...PDF/CP0105.pdf

http://www.classicperform.com/TechBo...oubleshoot.htm

http://www.classicperform.com/TechBook/BrakeBleed.htm

[Rochlow]

I did get some emails from CPP on things to try on narrowing the problems down. They suggested plugging the M/C to see if I get pedal. If I don't then, I know I have a booster/M/C issue..

Thanks for the links, Rob. I will give them a read later tonight.

[Rochlow]

So I spent the better part of 6 hours trying to get these brakes to work and I'm no farther ahead then I when I started. I gravity bled, vacuum bled and had the wife press the brake while I open/closed the bleeder.

I can't get the rear hose that goes into the caliper to stop leaking. Used different crushable washers and it still leaks. So if fluid is coming out air is getting in.. I'm totally frustrated with this truck at this point...

[VA72C10]

I understand the frustration. It can ruin your enthusiasm. The brakes on my shop truck build kept me from making it to a meet/show once with similar issues. Came down to a bad master cylinder and air getting in through old/weak rubber lines. Sounds like air is the issue here also at the caliper. Another CPP issue....

[jlsanborn]

It's a banjo-bolt connection at the caliper? What's the spotface look like at the port on the caliper? Is the tube hitting the caliper, keeping the hose end from coming down flat on the washers? Photo?

[Rochlow]

It is a banjo bolt and the face on the caliper is not smooth. That's a good possibility that I never thought to check. I will give it a look when I get home.

[lolife99]

I understand your frustration with CPP parts.
I have made up my mind I will only use Wilwood M/C from now on.
Aluminum body so they won't rust and a Super quality product.

Also check the "free play" at your brake pedal, and make sure it's not excessive.

[Rochlow]

Well, I'm beyond my wits end with these brakes. So since it has to go to someone else to have the exhaust and pinion angles done, I'm going to have them fix the brakes too.

[JakeDW]

I went from a chrome master to a wilwood master made a huge difference also using a wilwood prop valve.

Jake

[cericd]

Originally Posted by Rochlow

The paint is the same formula that GM used for years. One step process, sprayable right out of the can. Great coverage. My only worry is durability.. We will see when I pull it down to put it together.
Posted via Mobile Device

How did the frame paint hold up?

[Rochlow]

Originally Posted by cericd

How did the frame paint hold up?

It's held up a lot better than I expected.

[Rochlow]

So I'm trying to figure out the driveline angles currently. My issue is the trans yoke is hitting the cab and the trans angle is already down 6 degrees. However, I had to get engine mounts from Porterbuilt that raised the motor a half inch because the oil pan was hitting the rack and pinion.

Has anyone else ran into this problem running a first generation small block and a th350 trans?

[Rochlow]

I really wanted to get this taken care this weekend. Left a phone message and sent emails, there were responses but no resolution.

[jmedero]

Sorry man I know it's frustrating when your trying to wrap stuff up.

[ajgriffin]

cut the cab?

[lolife99]

Originally Posted by Rochlow

So I'm trying to figure out the driveline angles currently. My issue is the trans yoke is hitting the cab and the trans angle is already down 6 degrees. However, I had to get engine mounts from Porterbuilt that raised the motor a half inch because the oil pan was hitting the rack and pinion.

Has anyone else ran into this problem running a first generation small block and a th350 trans?

You have the frame level front to back and the trans is 6 degrees down, and it's hitting the cab?
(or is it setting on the wheels at ride height?)
My Ginger chassis had a first generation Dropmember in it and I was able to get it set at 5 degrees down.

[Hart_Rod]

Originally Posted by Rochlow

So I'm trying to figure out the driveline angles currently. My issue is the trans yoke is hitting the cab and the trans angle is already down 6 degrees. However, I had to get engine mounts from Porterbuilt that raised the motor a half inch because the oil pan was hitting the rack and pinion.

Has anyone else ran into this problem running a first generation small block and a th350 trans?

Roch - how high was the spacer that you put under the carrier bearing? I had to install a 2 7/8" one in order to get my angles close.