Caliper O-Ring Conversion

[Mark E.]

The RF caliper started leaking on my 1970. It was sleeved 12 years ago using lip seals. I'm hoping all I need are new seals and pads; brake fluid was changed every two years and the brake pedal pushed at least every two weeks.

What's involved with converting to o-rings? Are different pistons used?

[Joe L.]

Re: Caliper O-Ring Conversion

The RF caliper started leaking on my 1970. It was sleeved 12 years ago using lip seals. I'm hoping all I need are new seals and pads; brake fluid was changed every two years and the brake pedal pushed at least every two weeks.

What's involved with converting to o-rings? Are different pistons used?

Mark------


Yes, o-ringed calipers use different pistons than lip seal. Obviously, the seal is also different. I'm not sure if the boots are different.

[Joe R.]

Re: Caliper O-Ring Conversion

Nothing is involved. Just order you an O-ringed Caliper and send in the old one for a core! Nothing but bolting it on and bleeding as usual! Might be a good idea to hold your breath just in case!

JR

[E S.]

Re: Caliper O-Ring Conversion

Mark- I did the brakes about a year ago for a friend who had the similar problem you have-He had the stainless sleeved calipers, and the lip piston seals were all leaking. I got a "kit for each caliper from Ecklers which had new pistons, O ring piston seals, dust covers, and caliper half seals. I think each kit was about $50. Messy job,as usual, but have had no problems in over a year. Could have bought stainless sleeved calipers with the o-ring pistons and seals already installed for about $130 each- Less work-but then you have to do the "core charge" thing. I would definitely recommend the o-ring pistons and seals in any case
E.J.

[Mark M.]

Re: Caliper O-Ring Conversion

I started using the o ring conversion piston seal kits probably back in the 90's from VBP on c2 and c3 cars and my own. Been using a number of sources through the years for the sets now and not one of them I'm aware of has leaked. In the past I've changed OE lip seals on cars with few miles on the seals as the cars sit for periods of time. Perfect upgrade for these cars. The o ring design is also more forgiving with rotor run out which could pump air in system but I always keep run out at .005 or less. SS sleeve is also a must for DOT 3 and 4. It's nice to get sitting car out and not have one or more of the 16 pistons leak.

[Dennis D.]

Re: Caliper O-Ring Conversion

I bought o rings in the 90's from the developer ,zero tolerance.
Was told not to sleeve if honing cleaned up the bores. Never had another issue. Mind you the air pumping had gotten so bad I'd lose the brakes going around the block.

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[Mark M.]

Re: Caliper O-Ring Conversion

Dennis was the air pumping with the lip seals and do know what the rotor run out was on all 4 corners?

[Patrick H.]

Re: Caliper O-Ring Conversion

As Joe Ray suggests, check the price on swapping yours for those already done.
I have often found it less expensive to swap a caliper than to buy the O-ring kit and do it myself.

[Dennis D.]

Re: Caliper O-Ring Conversion

Air pumping. Bad runout in the rear. Remember reading about it in vette magazine 1980.

[Lawrence M.]

Re: Caliper O-Ring Conversion

I bought o rings in the 90's from the developer ,zero tolerance.
Was told not to sleeve if honing cleaned up the bores. Never had another issue. Mind you the air pumping had gotten so bad I'd lose the brakes going around the block.

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The great thing about the Zero Tolerance O ring pistons was that they were made of stainless steel and had a longer bearing surface to reduce the chance of a piston cocking in the bore. I don't think anyone is making stainless O ring pistons anymore. Mine have been leak free since '97.

[Joe L.]

Re: Caliper O-Ring Conversion

As Joe Ray suggests, check the price on swapping yours for those already done.
I have often found it less expensive to swap a caliper than to buy the O-ring kit and do it myself.

Patrick------

I don't see how buying the o-ring calipers can be less expensive than buying the kits and doing it yourself. The rebuilt calipers cost at least $100/each or $400 per car set. Then there's the shipping both ways---at least another 100 bucks. The o-ring conversion kits can be bought for about $200 for all 4 calipers. Shipping ought to be no more than about $10-15.

Rebuilding the calipers is not very difficult.

[Joe L.]

Re: Caliper O-Ring Conversion

I bought o rings in the 90's from the developer ,zero tolerance.
Was told not to sleeve if honing cleaned up the bores. Never had another issue. Mind you the air pumping had gotten so bad I'd lose the brakes going around the block.

[ATTACH=CONFIG]102804[/ATTACH]

Dennis------


I don't know if honing original caliper bores will work with o-ring pistons and seals but I can say, for sure, that it will not work well with original type pistons and lip seals. The piston-to-bore clearance is too critical. I would think it would be critical with o-ring pistons, too. Honing inevitably removes material.

Also, even if cleaned up original bores can be used, if DOT 3, 4 or 5.1 glycol brake fluid is used, water absorption will eventually cause more rust in the bores. Therefore, I'd never do a caliper rebuild with original bores.

[Dennis D.]

Re: Caliper O-Ring Conversion

Dennis------


I don't know if honing original caliper bores will work with o-ring pistons and seals but I can say, for sure, that it will not work well with original type pistons and lip seals. The piston-to-bore clearance is too critical. I would think it would be critical with o-ring pistons, too. Honing inevitably removes material.

.

Sold the car last summer. Never dealt with a brake issues in all that time. Believe I used dot 5 fluid as well.

[Patrick H.]

Re: Caliper O-Ring Conversion

Patrick------

I don't see how buying the o-ring calipers can be less expensive than buying the kits and doing it yourself. The rebuilt calipers cost at least $100/each or $400 per car set. Then there's the shipping both ways---at least another 100 bucks. The o-ring conversion kits can be bought for about $200 for all 4 calipers. Shipping ought to be no more than about $10-15.

Rebuilding the calipers is not very difficult.

Joe,

Just telling you like I've found it in the past.
Lately, calipers have gone up in price while O-ring kits are much less expensive than they used to be.

[Jeffrey S.]

Re: Caliper O-Ring Conversion

I did this conversion on the rear calipers on my '69 in 1998. Never a problem with run out or loss of pedal since. I purchased the kits fro Vette Brakes and did the work myself. The calipers had been sleeved some time before.
Jeff