Front brakes locked up

[SURFERDAVE]

I got my 88t back on the road after a couple of years on blocks. Replaced rusted brake lines, pulled apart and cleaned the calipers, replaced the pads and fluid. Drove the car for a weeks but the brakes didnt feel right. Bled them again, and again then went into a lot and slammed them on. The fronts locked up and stayed locked even though I took my foot off the pedal. I had to rock my car back and forth to release them to get home. Now they stay engaged when I press them. Any ideas? I was going to buy a caliper rebuild kit for my OEM calipers. I am not going to buy a big dollar brake set up, but was wondering if the calipers are the problem or if it is something else and do the OEM calipers rank with the middle of the road calipers from say an Auto Zone. It will be easier to swap out the calipers but I will be giving up my oems as a core. not sure how good the OEMS are.Thanks again

[interested!]

Originally Posted by SURFERDAVE

I got my 88t back on the road after a couple of years on blocks. Replaced rusted brake lines, pulled apart and cleaned the calipers, replaced the pads and fluid. Drove the car for a weeks but the brakes didnt feel right. Bled them again, and again then went into a lot and slammed them on. The fronts locked up and stayed locked even though I took my foot off the pedal. I had to rock my car back and forth to release them to get home. Now they stay engaged when I press them. Any ideas? I was going to buy a caliper rebuild kit for my OEM calipers. I am not going to buy a big dollar brake set up, but was wondering if the calipers are the problem or if it is something else and do the OEM calipers rank with the middle of the road calipers from say an Auto Zone. It will be easier to swap out the calipers but I will be giving up my oems as a core. not sure how good the OEMS are.Thanks again

Hi! generally, if the wheel wont turn , the caliper is sticking , if you intend overhauling , beware of pitting corrosion in the piston at the seal rub area.
Any deep pitting will allow the fluid to weep/leak under pressure .
Tip; before removing brake pipe from the caliper , fill the reservoir to the brim , cover with several folded patches of cling-film and hold in place with a tight fitting strong rubber band, this will act as a pipette , the lack of space will create a vacuum stopping the system from draining out ,so only the removed items will hopefully need bleeding at re-assembly .Edit: remember to remove the patch when bleeding .

[cre]

Also, don't use any lube that isn't SPECIFICALLY made for brake glides and calipers (I don't care how many years your uncle's been using mutton tallow on his Buick. )... Anything not made for the purpose is just BEGGING for a frozen piston or caliper glide.

As previously mentioned, if the pistons or the glides are pitted then replace them. You can get away with cleaning and sanding the glides until no roughness is encountered (start with 400 or 600 grit and move up to 1200) but I really don't recommend it for any purpose other than to get you by until the replacements arrive.

Make sure everything is well lubed and sliding freely.

[SURFERDAVE]

Originally Posted by interested!

Hi! generally, if the wheel wont turn , the caliper is sticking , if you intend overhauling , beware of pitting corrosion in the piston at the seal rub area.
Any deep pitting will allow the fluid to weep/leak under pressure .
Tip; before removing brake pipe from the caliper , fill the reservoir to the brim , cover with several folded patches of cling-film and hold in place with a tight fitting strong rubber band, this will act as a pipette , the lack of space will create a vacuum stopping the system from draining out ,so only the removed items will hopefully need bleeding at re-assembly .Edit: remember to remove the patch when bleeding .

Thanks for the info. I will use the plastic wrap, the same stuff I forgot to take off the turkey before I tossed it in the oven. That stuff is a little crispy so I will get some new cling wrap. I was kind of wondering if in 88 toyta made a caliper worth rebuilding and keeping or nowadays even a middle of the road new caliper is just as good. I hate to send in my core if these things are made well. I will break them down again and see where they are sticking. I used never-seize thinking it would work better, maybe thats the issue?

[cre]

Anti-seize is a very bad idea.... it's not really a lubricant in the sense that the calipers or other frequently moving components require. I would not be at all surprised if that was the problem. There are some places where you simply do not just use what's handy. Also, unless you applied the original grease ALWAYS clean out ALL existing grease to avoid mixing incompatible lubricants... Worst case scenario it may emulsify and lock the caliper from closing fully/evenly on the rotor.

[Bru]

I had a 1972 Honda AZ600 Coupe that the front calipers locked up and would not release.
I believe it was the brake booster that went bad.

[interested!]

Originally Posted by Bru

I had a 1972 Honda AZ600 Coupe that the front calipers locked up and would not release.
I believe it was the brake booster that went bad.

Hi! Thanks for reminding me! - I had a Simca 1501 estate many , many , moons ago , and the brakes locked on after applying the footbrake , reason ; the diaphram had split in the servo , jamming the piston in the on position , the only way I could move forward was to stop the engine , pump the brakes to remove all of the vacuum and this would allow the brakes to release. - cured by replacing the diaphram , - you could do that sort of thing then .