caliper issues

(87 244DL non ABS) So I noticed that my rear driver's side caliper had a screwed-up boot and so I opted to just replace it. Bought a new one from O'Reilly's and put it on. The end of the brake line did have fluid dripping out when it was disconnected for the record. I put the new caliper in, and the pads back in and everything was together so I went to bleed the brakes and it was taking absolutely forever and a ton of air was coming through but the pedal felt only a little bit squishy so I put everything back and drove it a bit and it felt okay but noticeably worse than usual. When I got back I noticed that the light rust on the rotor surface had been rubbed off by the drive on all corners except that rear driver's side. There was a visible gap between the pad and rotor even with the pedal completely pushed down, the pads didn't seem to move at all. I even got a pressure bleeder and tried that but got basically the same results of a ton of air and a little bit of fluid but the brakes didn't get any better. I did read that some of that air is being pulled through the threads on the bleeder so I pulled it out, checked that it wasn't blocked up or anything, and put some lithium grease on the top of the threads to stop it as much as possible but it didn't help. I know I've got to be missing something obvious here but I just can't figure it out.

I had a caliper on a Ford ranger get stuck after I pushed the pistons too far in and used an air compressor to push them out slightly, you’re able to get pressure in that caliper when bleeding right?

That's what I was thinking of doing, maybe the pistons just need a little persuasion, and I don't know exactly. There don't seem to be any leaks anywhere but the pads just don't move when the brakes are pressed. Thoughts on disconnecting the line and popping the pistons out a bit with an air compressor? If it works then great but I also don't want to mess up my brand new caliper.

DOA Rebuild.

Take it back to O'Reilly's, and use the cleanflametrap brake pedal stick™ next time when you open the system.

Just put a block of wood inside the caliper that way when you pressurize it the pistons won’t pop all the way out but they’ll move. But the brake fluid should be more than enough to get them moving, you might have a massive bubble in the line or caliper if it’s only that corner or somethings clogged

What about the rubber hoses disintegrating on the inside and blocking the fluid getting to the calipers, isn't that a thing on the 240's, especially if they're old?

Redwood Chair said:

cleanflametrap brake pedal stick?

Click to expand...

This will never get old

I used my own brake pedal stick™ (floor jack handle) and the pads weren't making any contact with the rotor. I'm thinking of putting an air compressor on it when it's still attached to the rotor so it can press just enough for the pads to make contact with the rotor and then reattach the line and try again or would the pistons need to move more to solve the potential problem? Should I try this or just take it back to O'reilly's and try to order a new one? As for the lines, it's possible, they look fine from the outside and there aren't any leaks anywhere but obviously, the inside could be a different story. The confusing thing is the amount of air coming out but also the fact that there is some fluid coming out too so I don't think that the lines are clogged up, but then again, who knows.

Also, the caliper did not seem brand new, I assume it was a rebuilt one of some sorts which could be an issue

My only thought is a clog in the line or a seized caliper because brake systems operate much much higher than your standard air compressor can push. Give the air a shot but if that doesn’t do it I’d say it’s seized. Make sure you closed that bleeder screw completely but that’s something you’d notice quick. Take the line off the caliper and see if fluid comes out when you push the pedal? Atleast confirms no clogs or issues between master cylinder and caliper