Seized front caliper - couple of questions

smetzger

03 P5 (x2), 09 Miata, 07 Mazda3, 13 Fit, 09 Ody
Seized caliper on my Blue P5. Not sure how bad it is. I am going to try and lube everything up but....

If I do need a new caliper...

1) Do they come with a piston or would I need to buy a piston also?

2) Preferred brands? or brands to stay away from?
 
I'm pretty sure they all come with pistons.
Mine came with everything installed. (RockAuto)

I think pistons are only sold separarely for those that want to rebuild their own calipers.


I remember you can get calipers with aluminum pistons which might fair better in the rusty north east.
 
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Well, lubed everything up. Put it back together.
Pumped brakes a couple of times and then while the front was still on jack stands started it up and put it in drive (did not give it gas, it is an auto tragic)

Left wheel rotated while right wheel did not. So, looks like its new caliper time.

How difficult is it to get that brake line off and then bleed the brakes afterwards?
 
Left wheel rotated while right wheel did not. So, looks like its new caliper time.

That's not necessarily true.

I did the same thing to find out which bearing was making noise.

One wheel would spin the other not. (eneven friction in the differential.)

I "carefully" stuck my foot on the spinning wheel and stopped it, then the other wheel would spin.

Try to carefully slow down the spinning wheel.

If you can't hold down the spinning wheel then the other side is dragging.
 
How difficult is it to get that brake line off and then bleed the brakes afterwards?

A flare wrench should work but if it strips you can try a pair of these.



They pinch up and grab the brake line connector.

Last resort is cut the brake line and use a socket.

The next last resort us to glue the socket onto the hex with JB Weld, let it harden, then wrench it off.
 
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Another test is to lift the front end and try to spin the wheel with the engine off.

If you can spin it then it probably isn't dragging.

Take your car for a normal drive then check and compare the heat coming off both front rotors. Check for the smell of burnt pads first. Reach in and touch the rotor and compare the temperatures.

Another test is to drive 2-3 mph on a flat smooth surface then put it in neutral and coast to a stop and see what it feels like as it stops. (no brakes)

If you can feel it stop and lurch back then something's dragging. (think of a bicycle wheel with the bearings too tight)
 
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If a caliper seizes, cleaning and lubing the slides probably won't help. Usually it is the piston that seizes, which gives you 2 options.

Rebuild the caliper (replacement calipers are cheap enough, nobody does this anymore. Not even sure they still sell the kits to do it)
Replace the caliper.

You may be able to clean it and have it work short term, but I wouldn't trust it more than a trip to the auto parts store and back to get a new caliper. Chances are you'll need new pads and rotors too because when they lock up, even a short drive will pretty much ruin the rotor. Even if it's not gouged or scored, the heat will warp and create spots that will create pulsations. Rotors are cheap.

I would consider doing both calipers... if one locked up the other probably isn't far behind. When mine went out I think they were like $60 each at oreilly. They're a little more money if you want a new bracket too, but the bracket is just a bracket so I reused mine. i got rotors for $20 each on amazon.

When it comes to belts or whatever, I'm all for trying to fix what's there. When it comes to safety related things like brakes, I don't mess around.

As for disconnecting the lines, it's just a 12mm bolt on the back of the caliper where the line connects with a banjo bolt. (I think it's a 12mm). All you need is a standard wrench, nothing special. First fill the master cylinder reservoir. The new calipers usually come with new banjo bolts and sealing washers. I always unbolt everything and do the line last so it's not disconnected for very long. It's the first thing I hook up to the new caliper as well. The idea is to lose as little fluid as possible. Once you get the new caliper mounted and everything put back together, top off the fluid reservoir in the master cylinder again. Then crack open the bleeder and leave it alone until you see brake fluid start to come out of the bleeder. Snug the bleeder and then have someone help you pump the brakes and bleed it manually. If you have a vacuum bleeder it makes it easy to do the job alone. As long as you don't let the reservoir on the master cylinder empty and suck air into the master cylinder, bleeding is easy. You only need to bleed the air out of the calipers you just replaced.
 
For those who use the search...
Symptoms - with both front wheels off the ground and in drive. right wheel did not turn unless I used my hands (with gloves) to stop the left wheel.
- In neutral and wheels off the ground I could turn the wheel, but it was difficult.
- 5 mile drive, speeds up to 60 mph, car vibrates a little but not enough that it causes concern, but... after drive the right front caliper is painfully hot to the touch, the left front caliper is warm.

Conclusion , although caliper is not completely stuck it is not moving as freely as it should and the brake pad is dragging.

So, I replaced the caliper. Some notes:
1) banjo bolt is 12 mm.

2) If you are replacing the rotors or the new caliper you got came with a bracket you need to take the old bracket off. Bolts are 17mm. My 12" breaker bar was not enough. Needed my 24" breaker bar.

3) I swapped the brake line fairly quickly. Only a little fluid leaked out during the process and bleeding was easy as there was not very much air in the system

4) This is only slightly more difficult than changing brake pads.
 
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Glad to hear you got it taken care of. I would either keep a close eye on, or seriously consider replacing the other caliper. In my experience, if one caliper seizes up then the other side is not far behind. On my cars, I'll replace both calipers, rotors, and pads so the whole axle is new brakes. Then don't have to worry about wrecking another rotor when the other one seizes, or doing the job all over again. It's worth the extra $60 for the peace of mind and time saved to just do the job once.

just my .02
 
Glad to hear you got it taken care of. I would either keep a close eye on, or seriously consider replacing the other caliper. In my experience, if one caliper seizes up then the other side is not far behind. On my cars, I'll replace both calipers, rotors, and pads so the whole axle is new brakes. Then don't have to worry about wrecking another rotor when the other one seizes, or doing the job all over again. It's worth the extra $60 for the peace of mind and time saved to just do the job once.

just my .02

Yeah, I haven't had that experience. If I was restoring then yeah, I'd replace both. But just keeping alive, I prefer to leave something alone that is working.

But, will keep an eye on it.
 
Hah.... guess what .....

You were correct LF caliper just seized up. Just took one more hard rain.
 
If you buy on Amazon (learned this through a lot of Google searches) there's three different types of calipers, unloaded, semi loaded, and fully. Unloaded is you have to build it yourself. Semi is comes built ready to bolt on but no brakes and fully is everything with brakes
 
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