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Seems these old cars only get more & more interesting as the years go by... (or read: I'm learning more about my car than I ever wanted to know!)
My 1967 car began leaking from right rear caliper a few weeks ago. Initially I ordered a single CC caliper but decided to return this in favor of a new "O-ring" SS-sleeved rear caliper set. As my rear rotor runout was about .008 I decided to replace both rear rotors also.
After returning home post-call on Friday and finding a little yellow UPS tag on my door, I zoomed out to the local distribution center. The gentlemen there were kind enough to search for an hour but successfully found my package. The weekend was saved! (sort of). Apart from needing to paint both rear calipers black, all was in order. I replaced the rear rotor & runout was about .007. Rear wheel bearing endplay undetectable. However, on attempting to install the caliper the mounting "ears" on the caliper would physically not fit onto the mounting bracket. The inclination angle was slightly incorrect. The caliper also "rubbed" the outer braking surface of the rotor.
After considering overnight, I attempted to fit the CC caliper (which I fortunately had not yet had time to return). It would fit onto the bracket a bit better but still rubbed the rotor. Changing back to the original GM rotor didn't solve the problem.
Finally I considered rebuilding the old caliper. After prying out the seals the bores look OK but the rear mounting ear has a small crack. And, you guessed it, this caliper too rubs the outer face of the (both) rotors. Interestingly, the caliper "straddles" the rotor perfectly at the rear but off-center at the top. All three calipers are Delco identical # units.
I analyze possible faults as follows:
1. Bent caliper mounting bracket - possible. I understand this usually occurs subsequent to rear wheel bearing failure, which has never occurred since I have owned the car (1986). The caliper I am attempting to replace I purchased in 1987 from SSBC & it fit on without difficulty. And in inspecting the bracket...it just doesn't appear to have that "tweaked" look; i.e. all the casting lines are sharp & not wavy, all the angles are parallel, no visible cracks. Both mounting ears are parallel when measured with a straight edge.
2. All parts "within tolerances" but together "out of tolerance".
I know I can have the rear ear on my current caliper welded & grind off some of the inner casting that "rubs" the rotor...but this is a "band-aid" approach & I would like to permanently correct the situation. Unfortunately I have limited ability to perform "heavy" work on the car in its current storage...and realyl don't want to try and remove the rear caliper bracket (half-shaft/flange/parking brake/etc.) unless I am convinced this is the etiology.
Any and all advice/help on this problem would be oh so greatly appreciated...
Thanks!
Carl
P.S. I know this all happened because I brought the parts home in a Ford...!
My 1967 car began leaking from right rear caliper a few weeks ago. Initially I ordered a single CC caliper but decided to return this in favor of a new "O-ring" SS-sleeved rear caliper set. As my rear rotor runout was about .008 I decided to replace both rear rotors also.
After returning home post-call on Friday and finding a little yellow UPS tag on my door, I zoomed out to the local distribution center. The gentlemen there were kind enough to search for an hour but successfully found my package. The weekend was saved! (sort of). Apart from needing to paint both rear calipers black, all was in order. I replaced the rear rotor & runout was about .007. Rear wheel bearing endplay undetectable. However, on attempting to install the caliper the mounting "ears" on the caliper would physically not fit onto the mounting bracket. The inclination angle was slightly incorrect. The caliper also "rubbed" the outer braking surface of the rotor.
After considering overnight, I attempted to fit the CC caliper (which I fortunately had not yet had time to return). It would fit onto the bracket a bit better but still rubbed the rotor. Changing back to the original GM rotor didn't solve the problem.
Finally I considered rebuilding the old caliper. After prying out the seals the bores look OK but the rear mounting ear has a small crack. And, you guessed it, this caliper too rubs the outer face of the (both) rotors. Interestingly, the caliper "straddles" the rotor perfectly at the rear but off-center at the top. All three calipers are Delco identical # units.
I analyze possible faults as follows:
1. Bent caliper mounting bracket - possible. I understand this usually occurs subsequent to rear wheel bearing failure, which has never occurred since I have owned the car (1986). The caliper I am attempting to replace I purchased in 1987 from SSBC & it fit on without difficulty. And in inspecting the bracket...it just doesn't appear to have that "tweaked" look; i.e. all the casting lines are sharp & not wavy, all the angles are parallel, no visible cracks. Both mounting ears are parallel when measured with a straight edge.
2. All parts "within tolerances" but together "out of tolerance".
I know I can have the rear ear on my current caliper welded & grind off some of the inner casting that "rubs" the rotor...but this is a "band-aid" approach & I would like to permanently correct the situation. Unfortunately I have limited ability to perform "heavy" work on the car in its current storage...and realyl don't want to try and remove the rear caliper bracket (half-shaft/flange/parking brake/etc.) unless I am convinced this is the etiology.
Any and all advice/help on this problem would be oh so greatly appreciated...
Thanks!
Carl
P.S. I know this all happened because I brought the parts home in a Ford...!
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