My front brakes were in bad shape. FL caliper had a leak. Here is before and after PIC. Working on FR now. Hope to be bleeding them out by tomorrow night. I can't wait to have brakes that stop again. (Though the compression brakes sure sound cool!)

 

Don't forget to bend that cotter pin over...
Later,
Sly

 

So after reading many posts on runout, and discussing with a colleague who is a motorcycle guru and a perfectionist, we used redbull fabricated shim's and non-scientific factoring on saturday and measured runout at ~.004. Close enough for Government work? NOT! We ordered Mcmaster shim material and went at it again. We ended up with .001 on both front's. Had to share it! Rear's are next!

Thanks to all who have posted on threads relating to runout. The information found on this forum set me in the right direction!

Used brand new NAPA performance rotor's and installed them out of the box after a little light steel wool cleanup.

 

Where did you get the McMaster shim material. I've got runout problems and was wondering what I was going to use to shim. Thanks!

 

Hi Wes,
My motorcycle mechanic friend got it. I think it was a McMaster industrial supply catelog. Give me a day or two and I can find out. It worked really well.

-patrick

 

Pop

 

I havn't heard back yet on the catalog details, but the shim kit has the following info:

Lyon Industries
www.lyonindustries.com
Brass Shim Stock
QQ-B-613 (1/2 Hard)
BRA-12

It come with 4x10 brass sheets .001, .015, and the .002-.012

For one Corvette it should be lifetime supply. (unless your Bubba)

 

McmAster-carr is a nationwide industrial supplier. www.mcmaster.com
You cna also check with www.mscdirect.com they will have SS shim stock kits with .001"-.020"? Use with a hole punch set to get a nice neat hole and trim with sissors or sheet metal shears.
Keep the runout under .002" and the same with the endplay in the bearings. tap the spindles and hubs to bolt the rotors on or you'll be changing the runout everytime you replace the wheels.

 

I'm going to take a wait and see attitude on bolting the rotor's to the hub. The NAPA rotors are not drilled, the documentation that came with them say's there is no need to do it. The runout was verified with the lug's torqued. I'm not sure whe the runout would change by taking a wheel on and off...but I guess I'm gonna find out if it does...

 

They are correct.
The rotors do not need to be riveted. runout would only change if dirt got between the rtor and hub while you were reassembling.

I don't rivet

 

Just for curiosity: Did you replace also the internal caliper parts (springs, "pistons", "rubber seals")? Do you use a special tool to install the rubber seals? Was the bleeding process easy?

 

The caliper looks like a new one, the old ones are original delco moraine units, the new one not

When using the original style seals and pistons you need to make sure the seals are on the right way and fully seated in their groove

The piston seals are easy installed, just get some thin bendable plastic sheet that is longer than the piston, smear some brake fluid on the seal and piston, wrap the sheet around the piston (with the seal already on it), put it in the bore and press the piston in, the idea is similar to a piston ring compressor.

Another method is to press the piston in till the seal butts up against the edge of the bore and then using a plastic stick make a sort of scribing motion around the piston while applying slight pressure, this will force the seal in the bore without damgaing it, if you hammer the piston in without protecting or guiding the seal you will end up taking the seal lip off on the bore edge

The dust boots are best hammered home with an appropriate sized socket. I like to coat the piston groove for the seal with a bit of black rtv before installing the dust boot

 

Excellent information!

 

Guys the rotor runout will vary with torquing the lug nuts, I tested it on the bench several times while dialing in rotors.This was done with new bearings, all parts cleaned and surfaced. Now, as I advised guys who buy those rear bearing greasers, or those that insist the 4 posi spring setup is great,it's your car do as you will,good luck.

 

Hi Guy's,

Just returned from first drive with new front brakes.
Much improved if I must say. Core objectives of even
braking on both wheels with no noise or chatter have
clearly been achieved. Pedal is still a little soft. Can't tell if this is from air still in the front's, something with the rears which I have not touched yet, or just the soft feel of the booster. BUt she deifinately stops nicely and holds pedal. No pulsating either. Nice and smooth!

The parts are all new NAPA performance. I decided to go local instead of dealing with mail order. If there were issues I wanted to be able to handle it in person. But there were none. I always havee good luck with NAPA, and do not have time in my day for rebuilding calipers.

I bled them out by gravity first, and then followed up the old two man pump method. Gravity bleeding is the real deal! I couldn't get any fluid to flow on the drivers side with a hand vacuum pump. I set up the gravity hose and went to dinner, and viola, fluid was flowing free when I returned a hour later.

I'm going to bleed them out one more time this week, and then go on the Skyline drive cruise on saturday and see how they do. I'll check the runout in a month or so after I rotate tires and see if gtr1999's theory on securing the rotor to the hub holds water.

Thanks to all for your valuable input on these topic's.

-patrick

ps; No matter what anyone say's, NEVER turn down a brand new rotor! I read that in some post on this forum and and it is totaly incorrect.

 

Thanks everybody for the help locating the shim suppliers!