SciVette

Hi all-

I have a '80 that I'm replacing all brake calipers, rubber hoses, and fluid on. Looks like PO installed two newer calipers at some point, but I have 1 old and 1 newer both front and back- want to start from scratch due to poor brake system maintenance and pulling to one side (old front caliper leaking and one piston stuck closed).



Question is this. I thought rotors were riveted to hubs front and back? My fronts are not attached (and of course I took them off without marking position in my ignorance- found no shims though). Do these look original? I see no rivet spots. Perhaps the rotors and hubs both have been replaced?




When I begin reassembly can I clean up and paint the parts first- brake shield, hubs (taping off threads), rotors (perhaps taping off caliper contact patch or not?) Will caliper paint work well or something else? I assume I'll need to use a dial caliper to check runout since I didn't mark my position... (Never noted wobble or pulsing prior to disassemble.)

Thanks for any help or advice you can offer. This is the largest job I've tackled singlehandedly thus far.

Easy Mike

Stock rotors (all four) were riveted to their respective hubs. At the least, it appears your fronts have been replaced in the past.

Ely

Mike:
You are more often than not correct but... in this case I'll challange you. I may be wrong but, I don't recall my fronts being riveted. The backs were for sure.
Note: the rear rotors will only go on one way and still have the ability to adjust the park brake.

Easy Mike

Note the rivets.


1981 production at St. Louis sometime after 12/8/80 (frame stencil).

Once upon a time your car had riveted front rotors.

speedreed8

""When I begin reassembly can I clean up and paint the parts first- brake shield, hubs (taping off threads), rotors (perhaps taping off caliper contact patch or not?) Will caliper paint work well or something else? I assume I'll need to use a dial caliper to check runout since I didn't mark my position... (Never noted wobble or pulsing prior to disassemble.)""

Hey Sci..... when i did my 79 several years ago the oem front rotors had already had the rivets removed at sometime but the holes are there. i replaced the front caliper pistons with oring style. they were already SS sleeved. i painted everything before reassembly, just dont paint the rotor pad surface face, i used engine enamel (black) and has held up fine, you cant see them anyway with the oem alum. wheels. I checked my rotor run out with a dial indicator/ magnetic base. i had to shim the driver side a little as i remember but i dont know how much now, passenger side was within specs. Bleed the lines good and you should be fine. goodluck......
.

Mike Ward

No C3 Corvette was built without rotors being riveted to the hubs or spindles. This would have made the final operation of machining the rotors faces to eliminate runout impossible.

SciVette

Thanks for the info. Bought a complete set of o-ring, sleeved calipers and soft lines from VB&P. I'm going to try to get a number of little things done in addition while all 4 wheels are off.

SH-60B

Are you sending your old ones back as cores? I did with the front pair and was never refunded the core charge for one, they said the other was beyond repair.

Sayfoo

You HAVE to use a dial indicator to check run out while installed on the car.
No matter if they are riveted or not, they could still be out, and that is the root of most c3 brake problelms.
Use the brake runout correction plates from Napa, Rockauto, etc. to correct if needed.

SciVette

All four cores sent to VB&P for refund. What's the general time-frame for their turnaround? I've read previous forum threads in which people say they sometimes drag their heels. I had them hold my new calipers until I sent the old ones to avoid the extra core charges.

Any place to borrow a dial indicator (loaner tool)? Already checked my local Pep Boys w/no luck. Or a place to purchase at a reasonable "I"ll only use it once every three years" cost?

DUB

Oreilly's may have one you can rent and return and get your money back. Maybe a NAPA in your area has one you can rent. Harbor Freight, Wholesale Tool They should be readily available in your area.

I do not use one with a magnetic base...because they are really hard to get to hold correctly and such. I got tired of getting it to be a solid foundation for measurement....so I have modified a "C" clamp and attach my dial indicator to it and I can basically clamp it anywhere on the trailing arm or front spindle and check run-out of the rotors or real wheel bearings when I can setting them up.

DUB

Ironcross

This is correct...The OP has had his rotors replaced sometime in the past and is now a simple front wheel drive hubless style rotors that merely slip on the hubs

No worry, the wheels hold the rotors now

Teem66

Sorry for the off topic but in Mike's picture (post # 4), does anyone know if (when they were placed on the gas tank) that was the usual location of the build sheet?

rponfick

Good time to run enough brake fluid through the system while bleeding to get fresh fluid everywhere.

Ralph

doorgunner

Rotors and hubs can be machined separately within .001" total run-out.....but the process takes longer. To cut cost, GM "finish-machined" the hub-rotor while riveted together saving themselves two extra machining steps.....and lots of money over the decades.

The C-clamp idea holding the dial indicator in place is a great idea....and even a cheap dial indicator is good enough/pays for itself the 1st time (may as well buy a 6" digital measuring caliper while you are getting the dial indicator (once you learn how to measure with them, your repairs/mods will be easier to do....FYI---back in the day----digital measuring calipers originally cost $300 each!)

Thanks Men for all the info...this rookie has a "break"-job on the to-do list......LOL.

Easy Mike

Sent you a PM.

Teem66

Does anyone know of a National store (Menike, Firestone, Tuffy, etc.) that does on the car rotor turning and have you had good results from the process?

DUB

No..I do not. But the fronts can be done as an assembly. AS for the rear rotors...IF you find a place that can do them on the car...I would make sure that the half-shaft was as level as possible so you do not run into binding up the universal joints while it is turning.

DUB