Front brakes dragging

[George Blake]

I did a C5 brake caliper and rotor swap on the Ty as well as an ABS delete from Mike Hood (thanks Mike!).
Finally got them bled today. Here's the problem. During the bleeding (had my wife pushing the pedal), there was a "pop" sound a couple of times. I thought it may have just been the calipers seating themselves. Popped a few times and then quit. Got all the air out(can't get any feedback from wife, doesn't care at all about cars). Now the problem. The back brakes are fine. Front brakes are both dragging what seems to me excessively. It actually takes effort to turn the front rotors by hand as the pads are still grabbing slightly. Is the proportioning valve messed up? It just seems odd that the fronts are dragging and the rears are fine. At least with the ABS out of there, I can rule that out. Nothing leaks amazingly. I guess this is the syty god's way of getting me somewhere....nothing leaks, I'll get him, I'll mess up the proportioning valve....ooooo....

 

[Foot Performance]

Re: Front brakes dragging

If you deleted the abs then propotioning valve is gatta be it. The pads should drag but shouldnt really apply.

Still have read drum or at they disk

Drums use a residuale valve to keep fluid applied dont know if the combonation/proportioning valve incorparates this but if you might have got the lines swapped in the ABS delete maybe this is cuasing problems???

 

[Foot Performance]

Re: Front brakes dragging

O yeah I love when you ask the wife how the pedal feels she just says "How am I supose to know" ( atleast thats what mine sayed) :lol:

 

[George Blake]

Re: Front brakes dragging

Still stock in the rear.
C5 fronts only.
Mike made the kits pretty idiot proof. Even for me
Big line fed the rears and little line fed the fronts.
The fronts just are NOT releasing all the way. If it was all four, I'd be worried about the brake booster. What a pain. I guess I can replace it. I didn't think the combination/proportioning valve needed to be replaced during a front brake only swap as long as the rears weren't touched. It's probably the good old 15 year old truck stuff going bad thing. If anyone has any other ideas let me know. The C5 calipers are newly refurbished units, not junk yard and both are acting the same way. I don't think both new units would fail simultaneously.

You should have your controller and TPS any day now:tup:

 

[Foot Performance]

Re: Front brakes dragging

.
You should have your controller and TPS any day now:tup:

Got the TPS friday I figure tomarrow or the next day for the contoler (not to change the subject) :tup:

 

[Loeryder]

Re: Front brakes dragging

Have you started the truck to let the vacuum build in the booster after bleeding?

My truck has 12" Baers on the F&R with Tuckers ABS delete and we have never messed with the prop valve.

I think the popping is normal when bleeding calipers from "dry".
I recall when we put discs on a camaro the calipers popped a few times when they were seating the first time on the car.
Once it bled out and we had vacuum in the booster everything was perfect.

I would go drive it and then jack the front up right away and check it again.

 

[ashman]

Re: Front brakes dragging

sounds almost like the pads/rotors are to thick. if there is no residual pressue on the calipers, there shouldn't be any grabbing (or only slight from the pads touching the rotors)

 

[Black Knight]

Re: Front brakes dragging

The popping is not normal George, I do a handful of break jobs a day on every make and model and have never heard one pop.

The front rotors should have no tension on them from the front pads until the pedal is applied. The rotor should almost feel loose and flopping around. The wheel bolted up is what will hold it tight. Once you let off the pedal the pads should release and not be tight.

If I had to take a shot in the dark guess without seeing it, I would guess the master cylinder got over stroked when you were bleeding the brakes. You can push it too far, standard is to only push as far as you would under normal breaking. Every car is different, if it's only a 1/2 inch then that's it, if it's 1 1/2 then that's it. You should never push to the floor as you can ruin a master.

Again, just a guess. Not saying it isn't your proportioning valve, but I've never seen one get ruined from bleeding brakes and have seen master's get ruined. :2cents:

 

[E-Rue]

Re: Front brakes dragging

yeah agreed... popping sound scares me. iv never heard the calipers pop before. id try to drive it and see what it acts like (make sure your emergency brakes work good before taking it out on the road) when you get some miles on it bleed the brakes again. check it again to see if its grabbing after a few weeks of driving.

e

 

[George Blake]

Re: Front brakes dragging

This morning I tried to just open the bleeder valve on the caliper. I figured, if something is not letting the fluid return, that would bypass all of it and release the pressure. The dragging was unchanged. I'm wondering if it's normal because the brakes are just so much bigger. If I spin them, they'll go almost 3/4 turn before stopping. I'll drive it a bit and see how it behaves after the engine is started and they wear a bit. The master cylinder looks like an easy job. we'll see how that goes if it's needed.
Am I thinking right that opening the bleeder valve should've released any pressure on the cylinders in the caliper? I can't see more pressure being applied with no brake pedal application.
The brakes are a matched set. The calipers are 2000 model year C5, the rotors are 2000 model year C5 and the pads are 2000 model year C5. Abutments are 2000 C5. Can't think of anything else on those. It's not Chris' kit. It lined everything up and the abutments are centered perfectly and the pads are evenly resting against the rotor. I've never done a larger brake swap before so I don't really know how they are supposed to act at this point.

I can't pinpoint where the popping was coming from. I was at the back right rear corner. Hardly no fluid was moving at all so I told my wife to go ahead and slowly push it to the floor. Lots of fluid moved then and that is when I heard the first pop. What she would do is push and she's kinda short so she'd reposition slightly and then finish pushing it all the way down. Pop pop. It did that a few times. She said it felt funny but then after bleeding them a while she said it felt better.

 

[Foot Performance]

Re: Front brakes dragging

Am I thinking right that opening the bleeder valve should've released any pressure on the cylinders in the caliper? I can't see more pressure being applied with no brake pedal application.


I can't pinpoint where the popping was coming from. I was at the back right rear corner. Hardly no fluid was moving at all so I told my wife to go ahead and slowly push it to the floor. Lots of fluid moved then and that is when I heard the first pop. What she would do is push and she's kinda short so she'd reposition slightly and then finish pushing it all the way down. Pop pop. It did that a few times. She said it felt funny but then after bleeding them a while she said it felt better.

If there was pressure like if a hose was bad it would bleed out the bleeder and the ones I have seen useally shoot out a pritty goood stream.

popping maybe the rotor sucking up to the hub??

 

[George Blake]

Re: Front brakes dragging

Just remembered, I did NOT have the lug nuts down tight on the rotor. When I went to bleed the fronts after doing the rears, I found it. I tightened them up and finished the procedure. That was probably the "popping". I took a c-clamp this morning and compressed the calipers and the fluid went back into the master cylinder reservoir and the rotors freed up. Applied the brake a few times(still haven't started the engine) and the driver's side is still hanging up a bit. I think it may be a bunch of new stiff parts as the issue. The spring loaded sliders that clip into the caliper may just be holding things up until they get worked back and forth a bit. It's not like the brake is applied dragging. If I put a wheel on it, it spins. It's just when I do the rotor by hand.

The 1993 corvette sawtooth 8.5" front wheels will NOT clear C5 calipers. It needs a 1/2" spacer to give an 1/8" clearance at the closest point. I have some Lowes generic spacers in there right now and have the Eibach hub centric 12mm spacers on order for them. They should hit the market in November. They are hub centric and have studs on them and 5 offset holes with special nuts that cap off the included studs. Right now I have to get it down and out of the way so I can start working on Kelly's trans.
I'll put up some pics of them and how it goes putting them on.

 

[Black Knight]

Re: Front brakes dragging

Your probably alright then George, I was under the impression you couldn't turn it at all. If you can spin it with the wheel on it more then likely good, if it's going 3/4 of a turn also that's probably free enough.

Did you gravity bleed the system first? Not that it matters now, but for everyone else you should always gravity bleed first to remove the majority of air, then foot bleed or pressure bleed.

 

[Foot Performance]

Re: Front brakes dragging

Your probably alright then George, I was under the impression you couldn't turn it at all. If you can spin it with the wheel on it more then likely good, if it's going 3/4 of a turn also that's probably free enough.

Did you gravity bleed the system first? Not that it matters now, but for everyone else you should always gravity bleed first to remove the majority of air, then foot bleed or pressure bleed.

just wodering have you ever used a vacuum bleeder it takes a lot of fluid but i did one and used half a quart threw each bleeder and brakes were awsome

 

[Black Knight]

Re: Front brakes dragging

just wodering have you ever used a vacuum bleeder it takes a lot of fluid but i did one and used half a quart threw each bleeder and brakes were awsome

Well we have both, there's a vacuum a.k.a. "vacula", and a pressure bleeder a.k.a. "R2D2".

I generally only use the vacuum, just to clean the master, but yeah you could definitely use it to suck fluid.

The pressure bleeder works awsome because it attaches to the master and forces clean fluid through the system. Hard part is it doesn't hook up to all master's and some you can't get to easy enough. Nice part is it automatically fills the master so it never runs out.

 

[SY2455]

Re: Front brakes dragging

The pressure bleeder works awsome because it attaches to the master and forces clean fluid through the system. Hard part is it doesn't hook up to all master's and some you can't get to easy enough. Nice part is it automatically fills the master so it never runs out.

This is the only way to do it.