70 - Brake calipers

[Stephen L.]

hi guys - have tried all the tricks and tips i know to get a stuck bleeder valve out - so, after rounding it the first try while using a 5/16 flare wrench, i have now torched/watered it to "shock" it - kroiled it - and put vice grips and still no movement - have also soaked it with a chelating rust remover thinking it might work its way up the threads eating the rust...still nothing - i am afraid to heat the caliper too much and risk making the metal brittle given its critical roll - any advice from those that have overcome this one before? - thanks! - sl

p.s. anybody ever tried this tool? http://www.brake-force.com/page/885368

[Dick W.]

Re: 70 - Brake calipers

Never tried an air hammer on bleeder screws, but I can see how it would work. Have used the hammer on other frozen parts of vehicles and been able to remove them

[Chuck S.]

Re: 70 - Brake calipers

I have to ask...Why are you trying to remove the bleeders?

Odds are your caliper bores are shot, and the calipers have to be sleeved, rebuilt, and restored. There's no point in removing the bleeders IMO...box'em up and ship'em off for sleeving and restoration, and let someone else worry about the bleeders.

Ask them to restore and return your original cores if they are in good condition. Have them install the pistons with the O-ring seals rather than the standard "cups"...the O-ring seals are much more forgiving of rotor runout.

There are a couple of vendors that specialize in brakes...others can recommend based on recent experience.

[Stephen L.]

Re: 70 - Brake calipers

just in that DIY mode!

[Stephen L.]

Re: 70 - Brake calipers

ohhh ... and the $492 quote from Vette Brakes (assume others will be the same) is not in the cards right at the moment ... plus, the bores look surprisingly clean - anyway...that's the thinking - sl

[Dick W.]

Re: 70 - Brake calipers

If the bores look good, there is probably a fair chance that they have already been sleeved. Not many original calipers out there anymore

[Stephen L.]

Re: 70 - Brake calipers

good point Dick - thanks - to my eye, i couldn't notice anything that obviously looked like a sleeve...but my eye is completely untrained - one clue is that when i took the pistons out, there was corrossion in each bore - i let it soak in evaporust for a few days (that is one of those "chelating" products that eats the rust but nothing else) and where the slight corrosion had been (both on the bore wall and at the bottom of the bore), the metal has a copper look to it on those spots (as opposed to the gray metal of the rest of the bore) - would this indicate that it has been sleeved? - thanks, sl

[Chuck S.]

Re: 70 - Brake calipers

ohhh ... and the $492 quote from Vette Brakes (assume others will be the same) is not in the cards right at the moment ... plus, the bores look surprisingly clean - anyway...that's the thinking - sl

What??!! Nobody told you??!!...The purchase price is just the first installment...That was the "bad money" going into the pit. There will be a LOT MORE "good money" following that first installment.

[Dick W.]

Re: 70 - Brake calipers

The sleeves will have a satin to polished finish. The good sleeves are stainless steel. Some of the auto parts stores are/were selling calipers with carbon steel sleeves.

[Wayne W.]

Re: 70 - Brake calipers

If you drill out the hole in the bleeder with the correct size bit, the lower seat will seperate from the upper and you will be able to first remove whats left of the threads, and then the tapered seat.

[Joe L.]

Re: 70 - Brake calipers

good point Dick - thanks - to my eye, i couldn't notice anything that obviously looked like a sleeve...but my eye is completely untrained - one clue is that when i took the pistons out, there was corrossion in each bore - i let it soak in evaporust for a few days (that is one of those "chelating" products that eats the rust but nothing else) and where the slight corrosion had been (both on the bore wall and at the bottom of the bore), the metal has a copper look to it on those spots (as opposed to the gray metal of the rest of the bore) - would this indicate that it has been sleeved? - thanks, sl

Stephen-----


The bores have to be PERFECT. If there is ANY corrosion WHATSOEVER affecting the bores, they MUST be sleeved (or, scrapped). With caliper piston bores, a "miss is as good as a mile". The bores CANNOT be honed, either.

You can usually tell if a caliper has been sleeved by looking about 3/4 of the way down the bores. This is the extent to which virtually all sleeves extend into the bore. So, you should see a circumferential "line" at the interface of the sleeve and the original bore.

[Stephen L.]

Re: 70 - Brake calipers

thanks guys...i'll have a closer look and report back -

[Dick W.]

Re: 70 - Brake calipers

Steve if you can feel anything, with your fingernails, other than hone marks in the bore, you will have trouble with the caliper leaking.