Things I am pondering today

[falfa62]

Pondering over my front disc brakes this evening. This is the situation, i am converting my front drums to disc using an oem style conversion using wilwood D52 calipers as an upgrade over the stock big GM units. The install went smoothly but the test drives did not. The brakes bite excellent and stop the car superbly, the problem is that the calipers will not release from the rotor enough causing the brakes to engage all the time (and get very hot). Any info will be much appreciated. Thank You.

[BluLightning]

Matt did you contact Wilwood about that?

[Bucky67]

Matt, does the brake pedal come all the way back up? That was the issue I was having; so I simply addes a "return spring" if you will on my brake pedal. How'd I figure out that my pedal wasn't being released all the way? My brake lights were staying on....

Now granted, mine never got as hot as you're describing. I'm guessing that my brake booster was my root cause, but I haven't had any problems since then. If you got any questions, hit me up again man.

[falfa62]

Matt did you contact Wilwood about that?

i havent contacted wilwood yet, it's on the to do list. i wanted to pick some freaks brains first

[falfa62]

Matt, does the brake pedal come all the way back up? That was the issue I was having; so I simply addes a "return spring" if you will on my brake pedal. How'd I figure out that my pedal wasn't being released all the way? My brake lights were staying on....

Now granted, mine never got as hot as you're describing. I'm guessing that my brake booster was my root cause, but I haven't had any problems since then. If you got any questions, hit me up again man.

Thanks for the quick reply Bucky. I have already ruled the master cylinder pushrod out. If anything there is a little bit too much play there(not good either) and my brake lights turn off when the pedal is released. I reinstalled the original front drums so i could make PowerTour this year and as soon as i get the chance (this weekend) the disc setup is going back on and more troubleshooting will surely begin. Thanks again.

[Bucky67]

Matt, by no means am I a brake expert, but it looks like you've ruled out the master cylinder pushrod. That's where my issue was. I'm wondering if there's not enough pressure, within the booster, to release the brakes. Since the brakes are bigger and more than likely dual piston, the original booster wouldn't have been designed to handle that. That's just my educated guess though....

Like Bob mentioned above, I'd def. give WilWood a call. I've called them several times for help, and their customer/technical support is pretty good. They've always been really nice and helpful to me.

Good Luck and Keep us in the Loop....

[falfa62]

Matt, by no means am I a brake expert, but it looks like you've ruled out the master cylinder pushrod. That's where my issue was. I'm wondering if there's not enough pressure, within the booster, to release the brakes. Since the brakes are bigger and more than likely dual piston, the original booster wouldn't have been designed to handle that. That's just my educated guess though....

Like Bob mentioned above, I'd def. give WilWood a call. I've called them several times for help, and their customer/technical support is pretty good. They've always been really nice and helpful to me.

Good Luck and Keep us in the Loop....

With the braking system being a manually operated system i can rule out the booster as well. I am stubborn and like taking the hard route usually (self educating i like to call it), although Wilwood will be getting a call this time if i cant figure it out. common sense is also starting to tell me that maybe the drum/drum master cylinder is causing the problem. although the bore size is sufficient to operate the brakes, the valves inside may hold to much pressure in the system. Disc brakes require considerably less residual pressure in the lines than drum. After i swap for a new master cylinder its time to ring wilwood! Thanks

[1956NY150]

i believe the master cylinder is not correct for the application

[Solsticefun]

I'm darn sure not an expert on brakes, but I had a 65 mustang do almost the same thing and it was in the brake proportioning valve.

[MIKEE]

master cylinder and proportioing valve issue.

[63 falcon]

master cylinder and proportioing valve issue.

I agree with Mikee

[RAIV70Judge]

Matt, do you remember our conversation at Coplen's shop? Double check and make sure you have the required washer/spacers between the caliper and the caliper mounting bracket........Hey Buckster...you remember this problem??? If the spacers are not in there, you are experiencing caliper bind. Without the spacers, the caliper comes in and turns upward, locking in place and not allowing the return of the caliper to its "home" position. We just had this sort of issue at Lane automotive with Boobs 56.

[falfa62]

Thank you everyone for your feedback on my disc brake problems. I think i have narrowed it down to either an issue of shimming the calipers or replacing the master cylinder. Jegs sells a master cylinder kit with reservoir , adapter fittings and hardware that i think i am going to try. Bore is 1.031" and the description states that it will work with discs on the front(up to 4 piston)/drums on the rear. Add a proportioning valve which the car does not have originally(only a distribution block inline) and that will answer the question of the master cylinder. All this is good as i planned on upgrading the master and adding a prop valve anyway. If the master is not the culprit i am braking out the shims.

[Bucky67]

Matt, did your kit come with shims? As Matt stated above, WilWood provided me with some tiny shims that I thought were useless but they are extremely important. I'd def. make sure you have the right shims. Good luck man and keep us posted!!

[cstmwgn]

Matt, did your kit come with shims? As Matt stated above, WilWood provided me with some tiny shims that I thought were useless but they are extremely important. I'd def. make sure you have the right shims. Good luck man and keep us posted!!

I am of the opinion that those calipers are floating calipers (OEM style replacements for the large body chevies). When we talked there was also some discussion of rotor width - have you eliminated that as an issue?