Seized front calipers?

[crazymikey]

i do beleive part of my car's seemingly running hot issue is actually my front calipers being seized.

After driving, the front wheels are extremely hot to the touch. Obviously, heat generated by dragging brakes while driving.

When I purchased the car, I checked the front brakes and the pads were low, and unevenly worn. The drivers side was much more worn out than the passenger side.

I took the pads from the white coupe I have, and after pushing the caliper piston back in, reassembling and bleeding the brakes, there was no difference made.

When driving, it feels like something is holding the car back. It doesnt accelerate and freely and smooth as it should.

Yesterday I took the caliper off, adjusted the pads, pushed the pistons back in and the car drove fantastic. Everything seemed to be freed up, until after a few brake applications, it seized up up again and is back to it's old shenanigans.

I read elsewhere that it may just be caused by a clogged proportioning valve (FYI, I've got an EXR ALB with rear discs). Either that, or perhaps my calipers are pooched? The car had been sitting unregistered for about 8 months before I bought it and jumped in driving it daily.

Any suggestions? I've got the Nissin calipers on my car, and I've got a pair from my EXR coupe I can swap over as test subjects.

[ExplodingCake]

Did you lubricate the sliding pins?

Clogging prop valve is very very unlikely.

[batever]

You could have a degraded soft brake line that is acting like a one way valve at the caliper. The lining on the inside of the line breaks down and collapses/peels off, in such a way that it will let brake fluid pass in o ne direction easily but not release it easily in the other.

I would clean and lubricate the upper and lower sliding pins on each caliper first , and see if that gets rid of the problem. If it doesn't, replace the soft brake lines at both front wheels.

[crazymikey]

That sounds like a plan. I'll have to get in there and try cleaning it up. All I did was just spray some PB Blaster around the outside of the brake piston, but obviously that didn't do anything.

I'll have a look at it and see if there's anything I can clean up.

[Davids92Accord]

there is a DIY on how to fix the problem check the DIY section

[crazymikey]

Ah..haha...didnt even think to check there. Durrrrrr

[crazymikey]

After reading the DIY, it sounds like that is exactly my problem. I know what I'm doing tonight.

Thanks for the tip!

[alan lx]

Interesting. I am having the same issue. I think the caliper is just sticking due to the rubber boot decaying. I am fixing to get into it a couple hours. Keep us posted.

[crazymikey]

I think mine is definetly just seizing up. It takes great effort to push the piston back in, even with my nifty little piston pusher tool, but the boots around the pistons look to be in good shape.

As I had mentioned the car had been sitting for 6+ months, I would say it is a safe bet that it is indeed the sliders that are seizing, and especially becausethe driver side pad had nothing left, while the passenger side still had about 50% left.

[Davids92Accord]

start by doing that first and everytime you replace the brakes you might as well grease them up.. thats what i do

[crazymikey]

Very good point. I went over the car when I got it, obviously seeing I needed new front pads, without knowing the calipers were seized, but I had my suspicions.

[YK86]

Hmmm....for the front caliper, the piston should be very easy to push back in. I use a c-clamp and an old pad and it's almost as easy as spinning a cap back onto a bottle. If it takes a lot of effort to get it to compress, the brake line may be collapsing like batever mentioned or the seal in the caliper is so bloated/bad that the piston has a hard time retracting. I have had this happen on cars that were left sitting for a long time and/or never had a brake fluid flush done.

You can tell if the sliders are seized. The 2 long pins would be very hard to take out when you were trying to remove the caliper. Once it's out, the pins are usually rust colored or has grease that has hardened all over it.

[crazymikey]

Just another question. If it turns out it's not, which it most likely is, the slider pins, are the seals replaceable or do I need new calipers?

[crazymikey]

Ok, so I got home, took my calipers off, pulled out the pins and they still seemed fairly lubed up.

I cleaned them off and soaked them with lithium grease and slid them back in. Put the pads back on, sprayed around the seal of the piston and pushed it back in and put it all back together.

It seems like it definetly did help, but I don't think the problem is 100% solved yet.

Never running stock alloys for any lengthy period of time, I dont know how warm they get, but all 4 of my wheels seem to still be fairly warm to the touch. The fronts being warmer than the rears.

The car does stop better now, and it feels like it's revving and accelerating a little more freely with less lag and hesitation. Just the warm wheels are causing concern for me, because I think they must still be dragging.

You can actually see burn marks on my rotors from where the shape of the pads have been imprinted on them.

[batever]

Ok, so I got home, took my calipers off, pulled out the pins and they still seemed fairly lubed up.

I cleaned them off and soaked them with lithium grease and slid them back in. Put the pads back on, sprayed around the seal of the piston and pushed it back in and put it all back together.

It seems like it definetly did help, but I don't think the problem is 100% solved yet.

Never running stock alloys for any lengthy period of time, I dont know how warm they get, but all 4 of my wheels seem to still be fairly warm to the touch. The fronts being warmer than the rears.

The car does stop better now, and it feels like it's revving and accelerating a little more freely with less lag and hesitation. Just the warm wheels are causing concern for me, because I think they must still be dragging.

You can actually see burn marks on my rotors from where the shape of the pads have been imprinted on them.

Glad that that helped. HOWEVER, that lithium grease will literally burn up in that application. FYI. I would redo it within the week using high temperature synthetic brake grease.

Sounds like you may need an overhaul of the caliper (replace the seal in the piston bore) to restore freer retraction of the piston and/or replace the soft brake lines as well.

good that it is showing progress though