C2 Rear Brake Rotors/Trailing Arms

[Larry Seaney]

Hope you guys can stand more brake questions. I've been surfing the archives but haven't found the info I need.
I am in the process of evaluating my brake system so I can get my 67 coupe on the road. I will have quite a few questions forthcoming.
I removed all my tires/wheels to check for rotor runout. My rear rotors are both >.005 runout. When checking them I noticed I could wiggle both of them side to side quite easily. I put the lug nuts on and tightend them to keep them from moving around.
What is the next step to take in the evaluation process? Of course I will recheck my measurements before doing anything too extensive. I try to use the measure twice cut once carpenter rule in my mechanical endevors.
Thanks for your guidance.
Larry

[Eugene Bliley (13136)]

Re: C2 Rear Brake Rotors/Trailing Arms

Larry,
I take a shot at getting you started and others will chime in. Since you can wiggle the rotors around, someone has already drilled out the rivets that secure the rotor to the spindle.

I would start by thoroughly cleaning the mating surfaces of the spindle and rotor. If they are not clean and relatively rust free, any measurements for TIR will not be good ones. Next, realize that if the rotors are original, there is only one way to install them and have all the holes line up properly. By holes, I mean the ones through the rotor and spindle that allow access to the parking brake mechanism.

I would install the rotors as above, tighten lug bolts and dial indicate for TIR. Before getting too concerned about the TIR of the rotor, I would evaluate the spindle and rear wheel bearings. The shop manual will help you do this.

If wheel bearings are good, then procede to indicate the rotors. If the TIR is greater than .005 inches, you'll have more work to do. Before doing any additional work, I'd rotate the rotor, with respect to the spindle one set of lug holes at at time and reindicate to find the location that produces the smallest TIR. You might get lucky and find a location that is much better than another. If so, you might consider making the decision to install the rotor in this spot, even if it making adjusting the parking brake impossible with the rotor installed.

That's probably enought to get you started, Larry. Report back what you are finding and we'll provide additional info.

Don't be in a hurry and get the rotors resurfaced until you're sure what you are dealing with. If they need to be resurfaced, it must be done while attached to the spindle and that means more disassembly.

Good luck,
Gene

[Larry Seaney]

Re: C2 Rear Brake Rotors/Trailing Arms

Gene
I looked in the publication section of NCRS and found two manuals. The 63-82 Shop Manual and the 67 Chassis Service Manual. I assume the 63-82 Shop Manual is the one I need. Would getting both of them be purchasing redundent information? (Spending more $ and getting for the same info?)
Thanks Again

[Jack Humphrey (17100)]

Expect the '67 CSM...

to be more specifically tailored to your car than the multi-year shop manual. It will cover the full line-up of 1967 Chevy passenger cars with a special section devoted to the Corvette body (Corvette was NOT Body by Fisher)...

[Eugene Bliley (13136)]

Re: C2 Rear Brake Rotors/Trailing Arms

Larry,
I'd take Jack's advice on this one. I have not seen the two manuals in question as I have a '65 and use the '63 Shop Manual with the '65 supplement.

You may want to check out the '63 and '65 manuals to see if there is enough related info. for the '67 to make them a worth while purchase. Regardless, when it comes to restoration, be sure to get an AIM and TIM&JG.

Best regards,
Gene