embarrassed I took it to the shop

[JointTech]

so this kind of came out of nowhere. I put in wilwood d52s, rotors, MC/booster.
Bench bled the unit with the powerbooster and prop valve attached.
installed the unit and bled the brakes with a vacuum bleeder.
brakes arent spongy but I cant panic stop. It wont lock the tires in the front period.
did some calling around and was told I was supposed to take the CPP mc off the powerbooster and bench bleed it by itself. Why it came assembled im not really sure...
Today I did that and rebled the brakes with the pump and hold method.
Bled directly at the MC again because of a hint from the parts store guy.
no change.
Ive bled at least 2 big bottles of fluid through this thing. theres no dang air anywhere in it.
Parts store guy says it has to be a bad M/C... theres not that much to bleeding brakes right. what else could it be. Im thinking it cant be, its a CPP unit and brand new. But then I thought back to the steering column thread and kind of thinking I should have thrown a new MC on for giggles.

Of course I already threw my old good one away.

anyway long story short I called the closet brake shop to me and before I knew it I had dropped the truck off to be looked at tomorrow.

dont know anything about these guys. Didnt take it to my normal person. Scotts hotrod was going to call me back tomorrow to schedule me in the shop. Not really sure wth I was thinking but sometimes I get impatient...

well hopefully these guys dont totally suck and mess it up worse. Or even better find out what I did wrong. I mean how complicated is replacing calipers and a mc? doh

[1972_Buford]

possible air in the caliper still. I have heard of air getting trapped in the caliper above the bleeder screw. try to position the caliper where the bleeder is at the highest point for the air to float up to it. so you will probably have to unbolt it, remove the caliper bracket and place just the caliper with pads on the disc with the bleeder at the highest point.

Disclaimer: I am not a certified technician/mechanic so try this at your own risk. Just something I saw in the past and it worked out nicely. good luck. let us know how it goes.

[mcmlxix]

The volume of the fluid in the caliper and the size of the bore in the MC could be your problem... If the D52 uses more fluid then the factory calipers, the MC bore size may have needed to be adjusted to match. Also, your distibution block may be resticting fluid transfer. Not sure what came on the truck. Last thing I can think of is rubber lines... Original or replaced? Old rubber can look ok but be bad on the inside....

[ls1nova71]

Don't know what kind of booster you have, but the small 'street rod' type just plain suck. No pun intended. I had a dual diaphram 7" booster on my '33 Ford and it never worked like iI thought it should. You couldn't lock the front wheels up unless you stood on the pedal HARD! Definitely not what you want.. I changed masters to different size bores and bled them forever, still never worked. A buddy of mine had the same issue with his dual diaphram 7", but a switch to hydroboost fixed it, so I did the same, COMPLETELY different car now! You don't have that nagging thought in the back of your mind of 'what if someone pulls out in front of me' any more. Long story short, stick to a factory size booster.
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[JointTech]

i got new braided lines from scotts.

The booster is the correct one for a C20. its about the same size as the old one.
I confirmed with CPP that the setup is 1 1/8" bore not the 1".

i got the booster/MC/Prop valve all as a kit from CPP. Its already put together so you dont have to figure out the pushrod thingy. It was the same thing I was going to get from Scotts but ended up with just the calipers from them. So I can only assume it should be the right setup for front calipers and rear drums.

I did have one thought though. to late now that its at the shop...
My buddy was cussing and yelling at the castle nut under the dash for the brake pedal. We were doing all kinds of contortions pushing the booster rod in while getting it attached to the pedal.
I wonder if the pedal just isnt in the right position and the MC isnt getting a full push of the rod.
I feel like Ill have to move the steering column to get anything any closer. It was tight in there.

[lolife99]

Do you have the correct set of D52's?
They make 4 different calipers.
2 different widths.
2 different piston sizes. (For front OR rear)
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[CC69Rat]

This may or may not help you but my setup is similar (not exact) and I had similar issues. I just couldn't get the pedal to feel 'full' .. it had a slight feel to it but not much.

I found this video --
http://www.youtube.com/watch?feature...&v=MdkBIVgDMAU

I am using a CPP booster and a Wilwood 1 1/8 bore MC. The 'Depth Correction Plug' is what ultimately fixed mine. I'm just curious .. and you even mentioned it .. that it almost feels like you're not getting a full push into the MC when you push the pedal all the way to the floor like the push rod is too short. (??) This made night and day difference in my whole braking system. It's not super touchy now but you can definitely tell it has 4 wheel discs. Keep plugging at it man .. you'll figure it out.

[TBONE1964]

I am not sure if it was mentioned or is your problem but did you put the new brak pads through some heat cycles? It is also refered to as "brake burnishing" and is done on semi's. I know you don't have a semi but it also works on passenger cars and light trucks. The truck needs to go through a series of stops from 40 - 50 mph to zero several times and allowed to cool...

If you google"brake burnish" you should get some good information.

It sounds like you covered the bleeding process ok and "air" may not be your problem at all. I have seen many a man bleed brakes with no further gain in brake performance because of this. You also may have a set of off the shelf bad set of pads.

I have done a lot of brake jobs and will say that although it is not a common problem it is a possible one

[LEEVON]

Don't be embarrassed about taking it to the shop. There is no way that you did something as dumb as I did. I put a new rear end under my Dad's car and all new brake hardware. The original stuff was tossed with the old rear end, so I was winging it from memory on the drum brake re-install. I got everything back together and it just wouldn't grab. I scratched my head for days. Dad finally decided to take it to the shop.

Some time later, I asked him if the shop found anything (expecting they vacuum bled the brakes or something). Mom got this look on her face and they locked eyes. OK, now I know something is up. Dad says, "Oh yeah, it's fine works great". Of course I know they're not telling me something so I made them come out with it.

Mom says sheepishly..."You put the brakes on backwards, on opposite sides." So now the cat is out of the bag Dad chimes in "Yeah, they had the whole damn shop in there looking at it, but your Mom told me not to say anything (chuckle)."

I stood a few inches shorter that day.

On the issue of bleeding. I use a mity vac these days. I had to "push" fluid up to the master cylinder from the caliper on a Harley once to get the air out, that actually worked PERFECTLY.

[rattle69]

Any possibility that you put the calipers on the wrong sides and the bleeders are at the bottom and not the top. Easy mistake I've seen done many times. This will never allow you to get all the air out.

[BruthaMan]

Originally Posted by rattle69

Any possibility that you put the calipers on the wrong sides and the bleeders are at the bottom and not the top. Easy mistake I've seen done many times. This will never allow you to get all the air out.

This is exactly what the problem was on my '78 restoration. Spent almost $2 grand on polished front/rear kit from performanceonline.com with chrome dual master cylinder. Even posted a thread here on the forums. It ended up being that the calipers were on the wrong side with bleeders at the bottom.

[Lattimer]

Don't be embarrassed. Sometimes you just have to know when to throw in the towel.

[JointTech]

D52s have 2 bleeders. one at the top and one at the bottom so you cant put them on backwards.

Also I bled them from the top and from the bottom. Bled them on my head, upside down, with green eggs and ham.

interesting point on the different sizes though. I dont rememebr seeing a part number on the actual caliper to check that.

[JointTech]

I remember the thread on the pushrod size. Im subscribed to it
I bought the kit from CPP with the booster already connected to the MC just so you didnt have to mess with that.

also i didnt heat cycle or burnish them. I have been doing 5-10mph panic stop tests and I had to drive it to the brake shop yesterday but thats it.

[rattle69]

If it has the bleeder on top and bottom then it shouldn't matter what sides. I usually track down the problem by pinching off the rubber brake hoses. If all are pinched and the pedal is still soft then you know that it's a problem from above like M/c or booster. If you get a rock hard pedal then you know the problem is from below. Release one clamp at a time to track down the problem. Anyway hopefully the shop you brought this too is good at tracking stuff like this down. Good luck

Burnishing goes a long way with bbk's. I've had soft pedal for quit a few stops until pads were broken in after bbk installs. This has had me wasting a lot of time bleeding in the past as well.

[JointTech]

well the shop just called and said theres nothing wrong with the brakes. everything is installed correctly and there is no air in the lines.
The guy at the shop said since I put on bigger brakes it wont stop the same as before... I didnt push him on it because my spanglish is terrible.
Ill go pick it up tonight and park it until i get the gumption to look at it again.
Im at a loss and annoyed. big shiney brakes that wont stop a scooter. should have stuck with OE and just replaced the damn pads.

[CC69Rat]

Take a bunch of pics and post em up. Maybe someone will see something.. ?
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[ezstriper]

done a few 4 wheel disc brake conversions using "complete" kits...only to have the same issue....was the master cylinder in most every case....there is a brake manufacture in NC I believe that mods the master cylinder to take car of the issue...no idea what they do but it works...basicly you are not getting enough pressure to operate the calipers..

[TBONE1964]

Originally Posted by JointTech

I remember the thread on the pushrod size. Im subscribed to it
I bought the kit from CPP with the booster already connected to the MC just so you didnt have to mess with that.

also i didnt heat cycle or burnish them. I have been doing 5-10mph panic stop tests and I had to drive it to the brake shop yesterday but thats it.

If I was in your shoes, I would try a procedure before I got to frustrated with it. It is free other than some time. Like I said earlier, look up "brake burnishing" on a google search and try it. If that does not work, I would see if you can get the pads replaced and see if that helps anything.

[rattle69]

Originally Posted by TBONE1964

If I was in your shoes, I would try a procedure before I got to frustrated with it. It is free other than some time. Like I said earlier, look up "brake burnishing" on a google search and try it. If that does not work, I would see if you can get the pads replaced and see if that helps anything.

I agree,

Some good hard stops to get through some of the zink plating can really help

[JointTech]

i did lookup burnishing. Ill try that on the way back from the shop.

[CC69Rat]

If you try a 7/8 bore it might give you a little more pedal ?
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[motorcritter]

The brake pushrod length can affect performance. And I second that 'pinch the lines to isolate the problem'- that will sort it out in quick order. I ran into the pushrod problem fixing the wife's Honda (and I'm an old Honda tech!). Pedal wouldn't grab properly- too low, even after the rears were adjusted right. Then the light went on. Reset the rod length (it's adjustable on a Civic), and no more tales of terror from her. Also, forcing fluid up from the caliper toward the master is pretty much the best way of getting rid of air. Learned that doing clutch slaves on Honda motorcycles. Saves a lot of pumping.
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[Hart_Rod]

Let it sit for a couple of days and give it a look this weekend...

[pumpkin]

I have run into a few cases where after doing a brake job the brake pedal is spongey, to the point you can push the brake padal to the floor. Take the vehicle for a test drive and it does not stop. As stated earlier, the pads have to be burnished, but there are times when the PADS are just too spongy. In the past I have done one of two things, replace the pads is one. The other is to carefully drive the vehicle to get the brakes fairly hot,then let it sit with a brake pedal depresser holding the brakes as hard as possable and let it sit for a few hours'