Pedal Rock Hard Take 2

[wiseman79]

Hmmm, first post seems to be Fubar'd, so here we go again...

I've installed the Steel Concepts kit. At first, it was pumping fluid fine to all corners, but leaked at the Wilwood residual pressure valve cause I used the wrong adapters. Installed the right adapters, no leak, but now the pedal was rock hard. It would pump fluid fine to the front, but when I bled the rears it would barely push any fluid and had to press the pedal VERY hard to get them bled. After talking with a few people smarter than me, was told I didn't need the residual pressure valve because I was using the factory combo valve and that had one built in. So yesterday I removed the Wilwood valve by replacing the entire line from the Master to the combo valve, where before the Wilwood valve was located midway in that segment. Now, same problem, fronts bleed fine, rears are very difficult to bleed, and the pedal is rock hard with almost no braking power. So what's up, is the stock combo not compatible with the wilwood master cylinder (can't see how, it's just pressure and fluid, right? What can't be compatible), is my new master cylinder bad, or something else entirely different?

Help, I only have seldom occasions to work on the car, so it's been almost two months off the road cause my attempts at a fix have been futile so far.

 

[GreenDragginBu]

Wiseman, i believe Cutlassracer had the same problem with a customers car, (pedal too stiff) I believe he said he needed to move the the rod up to the top pivot point.

I too have had some similar problems with my setup (steel concepts), but the problems seem similar to before i had bought the kit.

So with mine, i think it is in my front calipers or rotors, (there original) and my rotors look glazed like a burnt flywheel.

cause Travis told me that it is a progressive setup, and that i should feel it start braking as soon as i start to apply pedal pressure. Mine isnt like that the pedal moves about 1"-2" and it gets rock hard before i start to feel it slow the car, but if you cram it from there...the harder you push the hard it stops. like i said though, i think alot of my problems lie withing the front rotors being glazed, and that there may be air in the fronts....

 

[wiseman79]

I'll try testing the car again, but can't imagine the way it is can just be a hard pedal needing adjustment and not something wrong. I wouldn't take it out of my neighborhood or above 20 mph because stabbing the brakes only yielded a slow deceleration.

I'm wondering why it pumped fluid fine to the rear brakes at first, and now only trickles, made me thing something in the new MC cylinder failed. Could it be that they still need bled more? Like I said the rears were incredibly hard to bleed, maybe the pedal will stay rock hard if fully bled but will begin to actually brake? I always associated air in the lines with a mushy pedal but is this setup different?

 

[GreenDragginBu]

Your assumption is right on the mushy pedal thing....mine is real soft for that first 1-2", which is why i believe i still have air in there. on top of the fact of my rotors being glazed.

But as far as pedal feel goes, yes it is very hard on mine after the initial soft spot mine has.

This may be why Cutlass racer went to the factory manual hole, closest to the pivot point.

I can honestly say, the pedal is hard enough where i would not let my wife drive it.

but, me being like you, i dont have alot of time to mess with it. and i will be replacing the calipers, and rotors this winter and will try the upper hole on the pedal, to see if it gets better.

 

[Supe]

I was having a similar problem, and sent an email to Travis on Sunday. Here is what he had to say. My symptoms are rock hard pedal, maybe 1" total travel with all my weight on it. Granted my brakes also hadn't been used in a few years, and still have the same pads on them, so they definitely need to break in/get seated again:

The lines should come out of the master as Rear brakes come out of the front port and the Front brakes come out of the rear port. Now on the pedal the reason it is rock hard is that you might have a leak somewhere in the line. The pedal is agreesive but not that much. The master is setup for 70 % and 30% already so that is why you dont need a proportioning valve. Lets start there let me know Thanks Travis

 

[wiseman79]

Cool, at least I'm not alone. I'm at the point with my schedule that throwing money at it is preferred to spending several weekends diagnosing and trying different things. Was almost to the point of saying screw it ordering a complete brake package (assuming it wouldn't have it's own set of hurdles). This was a baby step towards a full aftermarket brake system anyways, but didn't want to fork out the bucks right now since my car needs alot of other stuff.

 

[wiseman79]

By the way Supe, are using the stock combo valve? I am, I was wondering if that was the problem, and if I shouldn't just use T-fittings and a metering valve up front/residual pressure valve out back. I can't imagine how the combo valve wouldn't work, like I said above, it's just fluid and pressure, can't think how these things wouldn't be compatible (maybe not ideal, but certainly compatible).

 

[Supe]

I don't even have a combo valve on mine. There was no chance in h#ll of getting the fittings out of the stocker, so with the new master setup and residual valve in place, I didn't forsee it being an issue, especially in terms of having too hard of a pedal. I'm going to take a peek on Thursday when I'm home to see if I have the lines backwards. Worst case scenario, I'll move the pushrod up to the stock hole.

 

[wiseman79]

I didn't want to say till I double checked, but I'm thinking my lines are backwards, since your post with Travis' email said opposite than what I expected. Anybody know which ports are which on the stock combo valve?

 

[355_79bu]

I didn't want to say till I double checked, but I'm thinking my lines are backwards, since your post with Travis' email said opposite than what I expected. Anybody know which ports are which on the stock combo valve?

I looked at the combo valve on my Malibu and here is how the combo valve is hooked up: If your looking at the combo valve mounted on the car, from the top where the lines come in from the master (the inlet side of the combo valve), the port nearest the front of the car is for the rear inlet, the one closest to the back is for the front inlet. Now, for the outlets, looking at the bottom of the valve the outlet on the back goes to the rear, the one on the front goes to the front.