CPP Prop Valve Leaking While Bleeding

[JonnyC10]

My new cpp prop valve is spraying fluid out of the front under the dust cap when bleeding my brakes. I read that this means the prop valve is junk???

[davepl]

Probably, but are you 100% it's not coming out of your line? Leaks can be deceptive, particularly pressure ones that spray.

If you're only 99% certain, clean and dry it all and then wrap some masking tape around the fitting on the front tube nut. It should be dry, at least on the inside, when you reproduce the leak.

[JonnyC10]

Yes. I saw it spraying out of it while a buddy was pumping the pedal. I saw the rubber cap bulging each time he pumped and I took the cap off and it started gushing when he pumped again.

[davepl]

Seeing it spray didn't convince me (it can bounce), but the bulging rubber part sure does. The OEM combo valves are non-serviceable (ask me how I know) but maybe that one has a fitting that can be tightened. If not, sounds defective to me.

[JonnyC10]

Got a response from CPP today.

Whenever a rear circuit is not fully bleed out and the front is done prior to getting the rear bleed up this can happen. Basically you are isolating the front brakes giving full fluid transfer to the front causing the front metering valve to be pushed forward against the metering valve spring opening up the front.

*

*So it sounds like you have taken care of your front banjo bolt question? If you have what you need to do is re-set the proportional valve as the tech guide shows under the “ proportional valve tool” *by clicking the valve back to center and fully bleed all the air out of the rear circuit before moving to the front.

*

Now I read on another forum that fluid was never supposed to come out of there no matter what.

[davepl]

So it sounds like they're saying that if you properly reset (center) the guts of the valve that it won't leak? Weird that it leaks at all, as the point of that system is to be able to stop the car if, for example, the rear fails entirely. I guess at that point leaking is the least of your worries, but it sounds odd.

Let us know what happens if you re-center it and try again. I'm curious.

[JointTech]

subbed. sounds like a horrible plan to ever have leaking brake fluid. this must be the corvette option. orrrrr the chinese option....

[JonnyC10]

Ya. I'm not happy about it. I reset it. I think. I don't have anyone to help bleed my brakes at the moment so u can't test it.

[JointTech]

duh. i just remembered i have that same prop valve. I scraped the sticker off...
Mine didnt spray but i bench bled the MC and vacuum bled all four corners so i never pumped on it until all the lines were full.
I did test the brake light by opening the cylider bleeders and stomping the pedal to simulate blowing a rear line. The light came on. No fluid came out the front.

[JonnyC10]

I bench bled the Mc but I don't have a vacuum pump.

[JointTech]

best $40 ever. i use it all the time. old gas, power steering, cleaning my e-cig. 1001 uses for a vacuum pump.
I like vacuum so much I just picked up an electric vacuum pump capable of drawing down AC systems. heh heh
and i have a Rainbow vacuum for my house.
ok ill shutup about vacuums now

[JonnyC10]

Have a link to the one you have?

[JointTech]

ok so either im way off on what i remember paying or the price has gone up a lot. Ive had mine a few years.
Amazon.com: Mityvac MV6835 Vacuum Brake Bleeding...
i got the kit that has the filler bottle so you dont run your MC dry pulling from the other side.

[JonnyC10]

Holy crap! Lol. Know of any good cheaper ones? I just need it for bleeding my brakes. Lol.

[JointTech]

get the single person bleeder. one way valve. works great.
ive used one like this
CTA Tools 1238 One-Man Brake Bleeder Hose - -...
or they have fancier ones like this
Amazon.com: CTA Tools 1250 One-Man brake bleeding...
i try not to have to wait for somebody to do anything on my truck. but since im a wimp I often wait for my stronger friends to swing by. brakes i can do myself

oh and most parts stores will have a one man bleeder in stock if you dont want to wait for amazon. they are common.

[JonnyC10]

The fancier one is cheaper. Lol. Ill go to autozone later and see what they have then. Thanks!

[JonnyC10]

So I called Cpp today and they said the tech guy I've been emailing is "misunderstanding" my problem and that fluid us NOT supposed to be coming out of the front of the prop valve whatsoever. And he is sending me a new metering valve to replace the old one. He says it unscrew from the front and then slide it out and install is in the reverse. Urg!!!

Btw, I bought a Mighty Vac 8000 from Oriellys.

[JonnyC10]

Well guys, had another metering valve failure!! This time while I was driving to the alignment shop. Not happy! Almost crashed my truck! Im so pissed! I had the shop check it out and he said the only place my brake system is leaking from is the meter valve. I have brake fluid all over my inner fender again. Called CPP and they said to remove the prop valve and send it to them so they can test it. Their customer service really does suck and I regret ever doing business with them. So now, I have to remove it, send it back, wait a week for it to get to Cali from New Hampshire, do what they gotta do and send it all the way back. It will probably snow before I get it knowing my luck.

On a side note, I need to replace my carrier bearing. Its shot. Shop quoted me $249 to replace. $75 for bearing and the rest in labor. Sound right?

[SHANE 73Z]

Johnny,

I am a member of a second gen Camaro meassage board NastyZ28.com.

There has been a ton of discussion about the replacement Gm prop valves. Apparently they are all made in China now and failures such as yours are common.

All is not lost though. If you have had it with CPP, Wilwood offers the same valve. HOWEVER, Wilwood pressure tests all of the ones they sell before they leave.

Hope this helps,
Shane

[JonnyC10]

Do you have a link? Thanks for the reply.

[SierraMtns]

Originally Posted by SHANE 73Z

Johnny,

I am a member of a second gen Camaro meassage board NastyZ28.com.

There has been a ton of discussion about the replacement Gm prop valves. Apparently they are all made in China now and failures such as yours are common.

All is not lost though. If you have had it with CPP, Wilwood offers the same valve. HOWEVER, Wilwood pressure tests all of the ones they sell before they leave.

Hope this helps,
Shane

Is this the one your talking about?

http://www.wilwood.com/MasterCylinde...emno=260-11322

[JonnyC10]

That one looks exactly like mine but black.

[SHANE 73Z]

Originally Posted by SierraMtns

Is this the one your talking about?

http://www.wilwood.com/MasterCylinde...emno=260-11322

Sierra,

That is the one. If you open the data sheet attachment it more details. I also stand corrected. I dont think Wilwood uses any of the Chinese stuff.

The brass valves are the ones that people are having trouble with.

Shane

[cdowns]

if your alone just use a cement block to help you bleed your brakes

it works fine you just need to think about it

[JonnyC10]

I ended up ordering one of those Wilwood units. Will let you know how it works out.