Caliper Resealing?

[Larry T.]

I had an issue last week with a noise in the front right of my car. Upon closer inspection it seems that one of the pistons in the caliper was not retracting properly. I pulled it down to inspect and all looks fine. When I go back together with a new seal kit do I do both sides at once or leave the side alone that is fine?

Thanks.

[Steven B.]

Re: Caliper Resealing?

I had an issue last week with a noise in the front right of my car. Upon closer inspection it seems that one of the pistons in the caliper was not retracting properly. I pulled it down to inspect and all looks fine. When I go back together with a new seal kit do I do both sides at once or leave the side alone that is fine?

Thanks.

Larry, when I did mine I did all of them even though only one was leaking, and to equalize them. I thought the others may not be far behind and since I was doing it anyway why not do them all and forget it for a few years.

Steve

[Joe L.]

Re: Caliper Resealing?

I had an issue last week with a noise in the front right of my car. Upon closer inspection it seems that one of the pistons in the caliper was not retracting properly. I pulled it down to inspect and all looks fine. When I go back together with a new seal kit do I do both sides at once or leave the side alone that is fine?

Thanks.

Larry------


If it were me, I would do both sides unless these calipers have been rebuilt very recently.

[Larry T.]

Re: Caliper Resealing?

Larry------


If it were me, I would do both sides unless these calipers have been rebuilt very recently.

Not recently, about ten years ago I would guess, and 3500 miles. I put about 1000 of the miles on in the last year. So low miles but quite some time. They were not leaking at all for what it is worth.

[Michael G.]

Re: Caliper Resealing?

Larry,

You might research/look into converting your calipers to o-ring technology. O-ring seals will require a different style of piston as well. According to my research great for cars like our that do not see many miles per year. The topic has been discussed many times.....found in the archives.

[Larry T.]

Re: Caliper Resealing?

Larry,

You might research/look into converting your calipers to o-ring technology. O-ring seals will require a different style of piston as well. According to my research great for cars like our that do not see many miles per year. The topic has been discussed many times.....found in the archives.

Is there any upside to Lip Seals versus O-ring seals? It seems like a no brainer to go to O-rings. Also, if I were to choose to stay with Lip Seals is there any upside or downside to Insulator Pistons other than originality.

Finally, is there a way to tell Dot 5 from Dot 3 or 4 brake fluid? A friend told me to put some on my finger and touch my tongue. Supposedly DOT 5 is not acidic.

Thanks.

[Joe R.]

Re: Caliper Resealing?

Finally, is there a way to tell Dot 5 from Dot 3 or 4 brake fluid? A friend told me to put some on my finger and touch my tongue. Supposedly DOT 5 is not acidic.

Thanks.

Larry,

I don't think it's safe to put any kind of brake fluid in your mouth in any quantity. Here's a more scientific way to test it:

https://www.forums.ncrs.org/showthre...=2667&uid=1182

Joe

[Domenic T.]

Re: Caliper Resealing?

My dot 5 is bluish in color and regular brake fluid is clear till it absorbs moisture then it gets amber.
I had dot 5 in my 67 for a while because it also keeps the rust away , but my pedal seemed to feel to solid. I don't have power brakes and the normal feeling when I pushed the pedal down was gone. I did a bleed from the botom up to the master cylinder as I do with dot 3, but the dot 3 had about 1/4 " cushion where the dot 5 had none.

Maybe some one with manual brakes that reads this can put their input.

DOM

[Joe L.]

Re: Caliper Resealing?

Is there any upside to Lip Seals versus O-ring seals? It seems like a no brainer to go to O-rings. Also, if I were to choose to stay with Lip Seals is there any upside or downside to Insulator Pistons other than originality.

Finally, is there a way to tell Dot 5 from Dot 3 or 4 brake fluid? A friend told me to put some on my finger and touch my tongue. Supposedly DOT 5 is not acidic.

Thanks.

Larry------


The lip seals provide a better brake pressure seal under high braking pressures but it's pretty much "moot" under normal STREET driving conditions. The downside is that the seals will not last as long as 0-ring type seals.

At the time the Corvette disc brake system was designed, both the lip seal and o-ring type seal systems were well-known and used in the brake industry. The Chevrolet engineers chose the lip seal system for Corvettes. I'm sure they considered the o-ring type design, too.

For racing purposes, I think the lip seal is the way to go. For the street, the o-ring conversion might get the nod. I still use lip seal for the street, though.

Insulated pistons help prevent as much friction-induced heat from transferring to the brake fluid through the pistons. That's ALWAYS a good thing. However, for street use, it's probably unnecessary. All 1965-E67 originally used insulated pistons. For late 1967-1982, only J-56 used insulated pistons, but of a different design than the 65-E67.

The other downside to insulated pistons is COST. The insulated pistons with insulators cost about 30 bucks each. You need 16 of them for the whole car, so that's about $500 worth of pistons.

[Paul J.]

Re: Caliper Resealing?

I had an issue last week with a noise in the front right of my car. Upon closer inspection it seems that one of the pistons in the caliper was not retracting properly. I pulled it down to inspect and all looks fine. When I go back together with a new seal kit do I do both sides at once or leave the side alone that is fine?

Thanks.

Larry,

Just do the leaking side, it will be fine.

However, if you change the configuration of one caliper, you should change them all. In other words, if you change to o rings, convert all of them.

Paul

[Michael G.]

Re: Caliper Resealing?

Larry,

Just do the leaking side, it will be fine.

However, if you change the configuration of one caliper, you should change them all. In other words, if you change to o rings, convert all of them.

Paul

Would agreed Paul. If the other side ain't broke don't fix it. You'll be fine.

Should you change one caliper to 0-ring....change'em all.

[Joe L.]

Re: Caliper Resealing?

Would agreed Paul. If the other side ain't broke don't fix it. You'll be fine.

Should you change one caliper to 0-ring....change'em all.

Michael------


Here's a common failure pattern: if one has a car with a leaking caliper and the calipers have not be resealed in a long time, it usually means the other caliper seal is "close" and, at least, at some point of deterioration.

When one side is resealed, the system is able to operate again at full performance. However, the other side being weak from deterioration, then more-or-less promptly starts leaking.

Now, of course, one then just reseals the other side IF AND WHEN it actually fails, right?. So, what's the big deal? Well, if one follows this course of action, then one gets to bleed the brakes TWICE. Bleeding Corvette disc brake systems can be a frustrating experience. I prefer to have to do it as little as possible.

Keep in mind that one does not necessarily have to do the rears in a case as described above. That's because the front and rear are completely separate systems in all disc brake-equipped Corvettes except 65-66 with manual brakes. For the latter, I would do all 4 calipers if one leaks.

[Michael G.]

Re: Caliper Resealing?

Good point when looking that perseptive Joe.

Frustration is mildly what I've felt when bleeding a Corvette system. This past weekend things went relatively smooth when bleeding the "completely new" system on a '66. Believe allowing the system to gravity bleed prior to manual bleed paid dividends. Did have some issues getting the bleeders to seat up....moderate weeping from the bleeders.

[John H.]

Re: Caliper Resealing?

Frustration is mildly what I've felt when bleeding a Corvette system. This past weekend things went relatively smooth when bleeding the "completely new" system on a '66. Believe allowing the system to gravity bleed prior to manual bleed paid dividends.

Michael -

The Motive pressure bleeder makes it a one-person, ten-minute job; best sixty bucks you can spend.

[Joe L.]

Re: Caliper Resealing?

Michael -

The Motive pressure bleeder makes it a one-person, ten-minute job; best sixty bucks you can spend.

John------


I got one of those some time ago but I haven't used it as of yet. I will be using it soon, though. I hope it works for me as well as you describe. It could put an end to my long-time "fear" of Corvette brake bleeding.