Eulentier

What was supposed to be a simple brake pad replacement turned into a nightmare last night. I am working on the front calipers only. I think I have everything figured out, but want to double check before I start today:

When I pushed the pistons back into their bores to fit the pads in, fluid squirted out from them. I had never run into this before so I simply ignored it and finished the installation. After completion, I noticed the brake pedal went all the way to the floor. I moved back and forward in the driveway a bit and it only stopped when at the floor. Pulled it back in the garage and I checked out these forums real fast and then realized the calipers needed rebuild/replacement.

I have an Advance Auto Parts right by me I will be visiting this morning. These are the two reman. calipers I'll be buying:

Front Right: http://shop.advanceautoparts.com/web...S_676756746___

Front Left:http://shop.advanceautoparts.com/web...S_676753136___

I am assuming the proper thing to do is buy these reman. calipers and install them. I will then need to bleed the front calipers, left first, then right second. After this, I should be good to go. Is this correct or will I need other parts for this project?

$150 for two front calipers sounds fairly reasonable. Not what I wanted to do, but I definitely need working brakes before it goes on the road.

Thanks guys!

69small block

check to see if they are s/steel sleeved lip seal or oring if car sits alot oring are better but if you execise brakes reguarly lips are ok to use ck out lonester rebuilders web site
be sure to flush the enitre brake line system to help clean up things while your at it put on new hoses too

G-Sting

I just finished all 4 of mine on the '79. Went with VBP's package of all 4 SS sleeved Delco-Moraine calipers, SS bleeders, new hoses, lines, pads, fluid, clips to install the pads (very helpful to compress the pistons). Also included a DVD. I am very pleased with them.

At a minimum, get new rubber hoses, too. New caliper bolts are inexpensive, and should be considered while you're at it (2 per caliper). You'll need a lot of Dot 3 brake fluid to bleed them, so buy the large container. And a 3/8" flare nut wrench is a good idea to prevent rounding the nut on the metal brake line when disconnecting. (Be sure to soak it in PB blaster or similar for a day before attempting to remove.)

When you have everything together. Here's what worked for me:
1. Soak line/brake hose connection at frame in PB Blaster for a day.
2. Remove caliper bolts and caliper and hang caliper out of the way.
3. Install new hose on caliper (use new copper gasket, dip thread tip in new brake fluid.). Tighten securely.
4. Install new caliper. Install new pads, pin & cotter key. Tighten caliper bolts to specs (I believe 70 ft-lb).
5. Clamp old rubber hose about 1/3 of the way down from frame with a vise grips to prevent fluid loss.
6. Cut old rubber hose below the vise grips.
7. Have a bucket or rag on floor below the line/hose connection. Get ready to work quickly. Remove clip from hose line. Then, unscrew (counter-clockwise as looking down from the top) the 3/8" line nut while holding the hose nut below with another wrench. Screw the new hose into the upper line fitting. Tighten securely.
8. Reinstall fitting clip.
9. Wipe all the old brake fluid off of the fitting/lines. This way you can check for no leaks after you bleed the brakes.
10. Bleed the brakes. Bleeding the brakes sticky.
11. Check all lines for no leaks. All bolts/connections secure.
12. Do the other side of the axle the same way.

I might have missed something... so be sure to check the books, too.

Enjoy!

Eulentier

Thanks for the information G-String! I will be following your instructions to the letter today. Having that list will definitely make this go much easier! I'll be sure to update when I've completed the project.

Lee H

Don't forget to check rotor run out. Even the best built caliper will suck air and leak if run out is excessive. When you install new rotors, you should use at least three lug nuts (backwards) to secure them, set up a dial indicator on the spindle, and check the rotor for lateral run out. Keep re-indexing the rotor until you find the location with the least total indicated lateral run out (should be less than .004" although several vendors clain 5-8 is OK) to avoid air-pumping which will suck air past the seals and cause a soft pedal while driving. Adjust the front wheel bearings first so you get accurate run out readings. If indexing does not work you'll need to use shims. This assumes fresh or fresh cut rotors.

jac_hmr

Wish I'd joined this forum sooner! Looks like you got some great responses. Just replaced all 4 calipers on mine.. one in the front and one in the rear were seeping... couldn't keep good pedal pressure.
I went with the OEM seals.. didn't choose the O-ring because I drive the car at least once a week or so. They are working great now.
Loved your opening line- one I seem to use quite often. "Simple job turns into a nightmare!" Ahh, gotta love it!
Good luck with your break job!
JR

vettes4evr

They only clam to have OE steel pistons, but nothing about stainless steel sleeves. I wouldn't waste my time with anything but SS sleeved calipers. You only want to do the job once for as long as you own that vette. I agree with the comments about replacing all rubber brake lines, or even going with the stainless braided lines that will give a firmer brake pedal. I've replace calipers on half a dozen Corvettes that I've owned over the years and I have to say that these cars are the EASIEST brake job to perform (except for parking brakes ). I don't touch the brakes on my daily driver cars though!

Eulentier

Started working on it today and everything seemed to be going fine... and then...

Went to remove the old brake hose that is connected at the line on the frame. Soaked the connection in PB blaster overnight. Used a back-up wrench and a flare nut 3/8" wrench as described.

When I tried to loosen the nut on the brake line with the flare nut wrench, it stripped anyway - so what do I do now?

EDIT: Used vice grips and got the line disconnected. Vice grips are absolutely wonderful.

Gilded_Splinters

I didn't want to start a new thread since I'm in the middle of chipping away at my brakes after work, but I have a question of my own.

I read that sticky article (excellent) and followed the bleeding procedures. This is my first time doing 4 piston calipers. I did the rears first, and sure enough, there were the 2 bleeders as expected.

The front calipers only have one bleeder. Is the second one hiding somewhere inconspicuous, or am I just not seeing it??

From the sticky....

“The rear calipers contain two bleeder valves (one inboard and one outboard) which necessitates the removal the rear wheels for bleeding.”

No mention of the front though.

Carlos840

The front calipers only have one bleeder each...

Gilded_Splinters

Thanks Carlos.

Why do you think? Why double in the back only?

Carlos840

I wish i could answer you but i have no idea!
Its still done on modern cars, saw the calipers of a Porsche 911 the other day and it had two bleeders in the back to!
Maybe its something to do with being furthest from the master cylinder!

G-Sting

Yessir. Well, I had to use them a bit, too. I just thought maybe yours would come apart easier than mine.

Hopefully, the rest is coming along well for you.


Could it be the near vertical angle of the front calipers allows air to rise for bleeding through one bleeder? The rear are only angled slightly... maybe requiring two. Just guessing here.

Eulentier

Finished the brakes up earlier today. The car stops on a dime! The brakes are absolutely great.

I would recommend to anyone trying this for the first time to have LOTS of PB Blaster on hand, a pair of vice grips and be prepared to run to the auto parts store to replace more things than you expected.

Thanks guys for all your help. Hopefully this thread will help someone else when they tackle this job, too.

Gilded_Splinters

Makes sense G. I looked at mine today and it seems that you're right.

I nearly toasted my last flare nut at a front rubber line today. Despite long and repeated soakings, it won't budge. The other three cracked right open as did the bleeders.

It's still relatively hexagonal, so tomorrow I'm going to (in the words of a friend's late father) "apply heat" and see what happens. I'll be glad if I can get it open and back together without leaks and save the line.

jackson

Ditto on Lone Star Calipers! When I got this car w/ great docs about 5 yrs back ... I could see it had fresh calipers & paperwork's "price" indicated top-shelf sleeved oring variety. Well, one started leaking a few weeks ago. I guessed it'd be no biggie to repair 'cuz it's got sleeves & orings ... just shove a new oring in ... WRONG! It had plain bores that'd been honed-out way big, plain old alum pistons ... both bore & piston corroded. It ain't just the bores that corrode ... OE pistons can corrode where the seal seats in groove & it'll leak across there too. So No quikNeasy fix for mine. Local corvette shop keeps Lone Star Calipers on shelf ... they're rebuilt w/ the good stuff ... I bought a pair for $200 exchange. I'd both read & heard Lone Star has stellar rep. Shop says they've used LS exclusively for a long time & they're guaranteed as long as I own the car & shop says any issue shop'll replace without hassle. Yep, I could've had another brand of calipers supposedly ss sleeved from Advance/Autozone for less $ maybe save $30-40 per wheel ... I went w/ Lone Star.

G-Sting

Good to hear of great results!


I wonder if it's possible to carefully tap on the top of the brake line nut with a flat head punch and ball peen hammer? Maybe this could jar the crud loose that's seized it? (And some how back support below on the hose side--keeping the clip in the frame bracket.)

I've read this can work on seized bleeder screws. Carefully tapping it square head on with a ball peen (without distorting it).

... it seems there's always one hard nut to crack in these machines.

sabre1981

I replaced both front calipers in the fall of '08 and the rear ones in the fall of '09. Just a few weeks ago I had to replace the front left caliper because, according to the mechanic, the sleeves rusted over winter and then the when the pedals got pushed the rust was pushed also and broke the seals. The caliper was not even two years old, but looked 30. I don't believe the leak started this year though, can't imagine it'd look that bad in less than a month, but I am no mechanic. I know it was said above, but pay attention to the sleeve. Learn from other peoples' mistakes.

Gilded_Splinters

Again G, excellent idea, particularly since popping the head of a frozen bolt is an old and effective solution. Trouble is that I couldn't really get a swing at it with so little clearance above.

I did cut a 1" long section of a 12 penny nail, held it with a needle nose Vise-Grip and managed to get in a few good whacks.

It loosened (with the help unfortunately of another vice grip) and went back together fine...no leaks and a very high and hard pedal.

I'm not sure if it was the hammer and mini punch treatment, the penetrating oil or the fact that I baked it with a propane micro torch until it was smoking that did it, but it's done.

I dropped it back on the ground with new brakes and lines, new rims and rubber and went for the first real, good feeling test blast of the year.

I rattled the windows of many Mennonite farmhouses in the hills up and around the Glen and it was awesome.

Thanks everyone for the tips.

G-Sting

GS: When you roll over a fresh pile of horse droppings in your driveway early some morning, you'll know they heard you.

... just kidding, man.

Glad it's back and running!