Rebuilding calipers, I have a little pitting in the cylinder...is that bad?

[Figit090]

I'm guessing it's not good but I'm not sure if I need to get a new/reman. set of brake calipers, the cylinder was sludged up and has some residue on the walls, and the pitting is about halfway down into the cylinder.

I'm not familiar enough to know if this is of much concern. I have the new seals and I'm just about ready to rebuild them, but if it's not safe to keep using these I'll buy a re-manufactured set. (unless those are crap too in which case I guess OEM from toyota...assuming the price isn't astronomical.)

 

[IBoughtASupra]

Check how far down the pitting is. The rubber on the piston sits on the edge outward towards the rotor. Check the travel and see the travel of the piston's rubber. If there is pitting inside of that area of travel you will need a new caliper.

If you need a set of housings, I have a set that are in great shape and never leaked. I can remove the pistons to see if there is any pitting inside the housing.

 

[Figit090]

Check how far down the pitting is. The rubber on the piston sits on the edge outward towards the rotor. Check the travel and see the travel of the piston's rubber. If there is pitting inside of that area of travel you will need a new caliper.

If you need a set of housings, I have a set that are in great shape and never leaked. I can remove the pistons to see if there is any pitting inside the housing.

Maybe I'm not understanding this right, but the rubber seal for my piston is in the cylinder wall, the piston is just that; no rubber unless you count the dust boot, which doesn't provide any pressure seal.

 

[IBoughtASupra]

Whoops, I had a brain fart. It's okay. It's okay if there is a little pitting. It is is a deep gouge, then replace it. If it is tiny specs, in random places, it will be fine.

 

[Figit090]

well, it's not specs, on the one i have apart, it looks like an isolated spot, and it would depend on your definition of deep. Fingernail catcher for sure, but not more than a mm deep.

It's still below the rubber seal though, so come to think of it, if the rubber seal does all the holding like I am assuming, does any pitting really matter? The fluid will leak up to it anyway, right?


Kinda worried about my master cylinder with all the gunk I found in the cylinder. I did some searching and learned that brake fluid is very hydroscopic and will induce water and then rust...
i hate how things turn out much more expensive than initially estimated.

 

[IBoughtASupra]

Pictures?

Change the master and flush the system.

 

[Figit090]

I'll take some images of the cylinders and post them this evening.

I haven't checked the master though...

I have suspicions from when I was driving that it leaks internally, because I depressed the pedal and held it while the car was running and it eventually goes all the way to the floor when I push it hard. I read that is indicitave of blowby in the master cylinder... but i'm not certain how breaks should function. If it IS bad, I don't know what else can cause it?

 

[IBoughtASupra]

Change the master. If you have a leak in the braking system, it will cause the pedal to move towards the floor when depressed.

 

[IBoughtASupra]

When I redid my brake system, I changed the master, removed the ABS and I rebuilt the calipers. I do have a BBK to go on the front. I loosened each bleeder one at a time and then filled the master and pressed the pedal until clear fluid came out of the caliper. Did that to each caliper and flushed everything out.

 

[Figit090]

OK, here are images of one cylinder, I haven't looked at the others yet.

To me it seems that fluid will get up to the seal anyway, so the pitting won't effect the seal or performance, it will merely take a few drops of fluid to fill....right?

I will replace the master cylinder unless there's another cause of the pedal going to the floor while the car is on, sadly I can't afford the 280 dollar pricetag for a toyota model, and I hear refurbishing them (assuming I have a toyota unit in the first place) is difficult. I'll just get a reman or other aftermarket part for that, probably.

I'm hoping I will be ok with these cylinders though since the fluid won't leak out the piston, as far as I can tell.

 

[IJ.]

They seal on the piston and the seal groove in the calliper, if those 2 surfaces are ok it's be fine.

 

[IBoughtASupra]

Get the master overhaul kit, it will work.

Get some 800 sand paper and go to work. Make sure to use soap water, act as if you are wet sanding a car. Steel wool would work as well, run the surface until you get out that build up. I had the same and the sandpaper took it out.

Start on the higher spots first focusing in them and then work your way to make all those spots even and after that clean the whole bore of the housing with the sandpaper.

 

[mecevans]

A small hone would be best.

 

[3p141592654]

Reman calipers are cheap. I wouldn't use those, they look deeply pitted. A couple of thousand psi on a hard stop and those things could blow apart.

http://www.ebay.com/itm/Supra-Front...Parts_Accessories&vxp=mtr&hash=item1e69aa0e9e

If the master bore is not pitted, then get the toyota master rebuild kit.

 

[IBoughtASupra]

Rock Auto, a vendor on here has great prices.

 

[Figit090]

They seal on the piston and the seal groove in the calliper, if those 2 surfaces are ok it's be fine.

That's what I was thinking. Thanks Ian.

Get the master overhaul kit, it will work.

Get some 800 sand paper and go to work. Make sure to use soap water, act as if you are wet sanding a car. Steel wool would work as well, run the surface until you get out that build up. I had the same and the sandpaper took it out.

Start on the higher spots first focusing in them and then work your way to make all those spots even and after that clean the whole bore of the housing with the sandpaper.

I'll definitely clean the cylinders, or were you talking about the master? Looking at Rock Auto their prices are SUPER cheap, I could get a reman beck-arnley or wagner master cyl. that's new for $101 shipped!

Reman calipers are cheap. I wouldn't use those, they look deeply pitted. A couple of thousand psi on a hard stop and those things could blow apart.

http://www.ebay.com/itm/Supra-Front...Parts_Accessories&vxp=mtr&hash=item1e69aa0e9e

If the master bore is not pitted, then get the toyota master rebuild kit.

BLOW APART? What makes you think they'd blow? I wouldn't think the integrity would be that compromised but I don't really know, i'm curious if you've seen one blow before though. it is a lot of pressure...
Thanks for the link sadly there's only one but I will look on ebay/rock auto now. rock auto seems super cheap...

Rock Auto, a vendor on here has great prices.

Thank you, reliable? Prices look amazing I wish I'd bought my whole order from them!

 

[Figit090]

Could I get more tips on if the caliper cylinders could actually explode? As IJ. mentioned they will seal fine.

I'll likely replace the master cylinder, and thought my caliper cylinders would be fine but...that comment about them potentially exploding worries me...lol.

Also, are both anti-squeal inserts necessary? I only have one little shim on my brakes, PO must have removed whatever else was there...

 

[3p141592654]

That would be a worst case scenario. There is a lot of metal around the caliper cylinder, so the corrosion would have to be very deep to rupture. Still, calipers thermal cycle a lot, and cracks can form with the pits you have. For $30 get a rebuilt caliper and some piece of mind.

 

[Figit090]

Valid points, the corrosion isn't deep enough for that, but the idea of the entire caliper cracking is conceivable.

I wish I had tested my master cylinder after a brake bleed but I suppose assuming it's in comparable condition is a safe bet.

Any advice on what company to go with for these parts? Lots of options on rock auto...

Wagner, Beck-Arnley, Centric, Raybestos, Nastra, Cardone... all for just calipers.
Beck/Arnley, Wagner, Bendix, Cardone, Dorman, all for the MS..


Do I need a new bracket for the calipers, or can I reuse my old one? Thanks again, you've all helped a lot, as usual!

 

[IBoughtASupra]

Reuse the old brackets.