caliper question

[1990LTD]

How do you know a brake caliper is bad?


The rear brakes on my aero function but I don't know how perfectly. They stop the car when I'm rolling it around in my driveway but that's a lot different than stopping it at 100mph.

The pads and rotors obviously need to go but I haven't touched anything yet aside from removing the wheels and putting a bag over everything to keep rain off of it. Probably didn't need to. Coincidentally, I haven't been able to do anything BECAUSE of the damned rain.


If the bleeder screws aren't seized, and the piston moves freely in the bore when I use a C clamp to push em back, am I good to go?

I'm not opposed to replacing the calipers but if I can get away without it, that's like 50 bucks in my pocket for bearings and junk like that.

[johnunit]

try twisting the piston (only a few degrees) in it's bore with a pair of pliers or similar. it should move somewhat freely. Also make sure everything slides freely. I can't picture the rear calipers on an aero vic too well, but basically make sure nowhere that is lubricated and has things sliding on it is overly pitted and that everything moves.

[1990LTD]

[Brown_Muscle]

If the piston moves baqck in with the C clamp and the sliders move freely the caliper is fine. Make sure the bleeder screw can be loosened and doesn't snap of in there. and While you do the brakes lubricate the sliders as well, it's often over looked

*edit* if it is the twist in type then same goes for twisting it in, i have no idea on the vic calipers.

[johnunit]

yeah, that looks like your main thing is going to be the piston moving freely both in rotation and in-out.

Make sure you get all the rust off the caliper bracket where the pads ride and that you lube the shims/sliders that are inbetween. Ideally, you'll get name brand pads that come with new shims... I think shim is the term, no one ever uses a name at work. The chromeish little sheetmetal things. Lube them on both side (contacting the pads and contacting the caliper bracket) and make sure all scaley/loose rust is removed from the caliper bracket. Rust buildup in the caliper bracket area where the pads ride can cause the pads to stick. I've seen where you need a BFH to knock them loose from their seat, meaning they clearly aren't retracting from the rotor properly.

Hope this helps. I might have covered stuff you already know but I don't know if you've dealt with calipers like that before.

[1990LTD]

thanks guys. i'll pull the calipers and see how the movement is. they look pretty rusty on the exterior so i'm not expecting them to be perfect.


will probably just get the cheapest calipers i can at the parts store just for the sake of having new/guaranteed brake parts on there. i didn't price them yet but rotors and pads together were only about 90 bucks.

[1987cp]

I've seen where you need a BFH to knock them loose from their seat, meaning they clearly aren't retracting from the rotor properly.

I used to do this more often than not; since then I've bought a couple of big C clamps specifically for retracting caliper pistons.

[BerniniCaCO3]

do you have rear drums or rear disk brakes btw?

Probably, they all work.
What you want to watch out for though is if you have floating calipers and one pad wears MUCH faster and the other looks near new... seized piston

[1990LTD]

I have rear drums but a donor aero with better gears and discs. I'm amassing brake parts for the disc brake axle right now.

[91waggin]

Also inspect the rubber boot around the piston. If it looks crackey, replace caliper. I had a Civic I worked on recently where the boot had actually torn and the car would piss brake fluid every time you stepped on the brakes.

[86VickyLX]

You need torx sockets to remove rear calipers.

[1990LTD]

any idea what size? i have a few t50 bits but that's about it

[Lincolnmania]

t40 or t45 and some are allen