anyone ever change their caliper seals?

[LMHmedchem]

Hello,

I am sitting around waiting for a rebuilt rack and pinion that will be shipped eventually, I hope. I am also waiting for it to not be 14 degrees out like it was yesterday morning.

I have my front calipers off because I am doing some suspension work along with the rack and pinion. I always bring my calipers into the shop and clean them well when I do the brakes. I have toyed with the idea of painting them with POR-15 Rust Preventive, but that's a bit over the top even for me.

I will rebuild the calipers with new slide pins, vibration dampener bushings, boots, bolts, and slippers. Most of this comes with the brake pads. The rest is only $4 per wheel so I think it's well worth it.

I was wondering if anyone has replaced the seals on their calipers,

RAYBESTOS WK2857 Element3 Caliper Repair Kit ($4)

I would go ahead and do this as well if it's not a nightmare. I would rather not get the calipers taken apart and then realize that I can't get them back together, or get the seals sealed, etc. These are the original calipers, so they are going on 20 years old. Everything needs to be replaced eventually but apart from looking rusty like everything under a truck in this part of the country, I have never had any leaks or freezes that I know of.

If anyone has any experience with this I would appreciate some advice. Is this a good idea or should I leave well enough alone until a problem appears?

LMHmedchem

 

[smalltownusa]

Hello,

I am sitting around waiting for a rebuilt rack and pinion that will be shipped eventually, I hope. I am also waiting for it to not be 14 degrees out like it was yesterday morning.

I have my front calipers off because I am doing some suspension work along with the rack and pinion. I always bring my calipers into the shop and clean them well when I do the brakes. I have toyed with the idea of painting them with POR-15 Rust Preventive, but that's a bit over the top even for me.

I will rebuild the calipers with new slide pins, vibration dampener bushings, boots, bolts, and slippers. Most of this comes with the brake pads. The rest is only $4 per wheel so I think it's well worth it.

I was wondering if anyone has replaced the seals on their calipers,

RAYBESTOS WK2857 Element3 Caliper Repair Kit ($4)

I would go ahead and do this as well if it's not a nightmare. I would rather not get the calipers taken apart and then realize that I can't get them back together, or get the seals sealed, etc. These are the original calipers, so they are going on 20 years old. Everything needs to be replaced eventually but apart from looking rusty like everything under a truck in this part of the country, I have never had any leaks or freezes that I know of.

If anyone has any experience with this I would appreciate some advice. Is this a good idea or should I leave well enough alone until a problem appears?

LMHmedchem

I rebuilt both the front and rear about two years ago. I purchased all the seals (Concentric) from Rock Auto. I cleaned up the calipers using electrolysis, painted them with caliper paint. Then reassembled with the new seals. The hardest part for me was getting the seals/piston back in the bore. I did locate a lubricant that helped immensely. If you need I will try and get a name for the lubricant.

 

[LMHmedchem]

Thanks for the info, a few questions,

How do you get pistons out in the first place? I have collapsed them back into the caliper body as I normally would before putting the caliper back on. Do I need to hook them back up to the pressure hose and pump the brakes until they come out?

What lubricant did you use to reinstall the pistons?

Did you replace the bleeder valve?

What did you use for paint? I really like POR-15 so I guess I would get something like this,
POR-15 Caliper Painting Kit ($37, supposedly enough for 4 calipers)

Is there a video for the procedure? Yes, I could just look for myself but since you had success it would be nice to see the same video that you used if you found a good one.

LMHmedchem

 

[boominXplorer]

Compressed air is key to rebuilding calipers. You pop the pistons out with air and you can use it to assist pushing the seals out when installing the pistons back in the caliper.

 

[smalltownusa]

boominXplorer beat me to it. Yes I removed it with compressed air> The air nozzle had a rubber tip to seal around the bleeder valve threads.
Just go slow with the air don't want things flying around. I hit it with the compressed air several times, and they will "pop" when they come out.

The lubricant I used was a Centric brand assembly fluid part number 500-1000 Amazon has in on line ~$22 a pop. Wasn't able to get the pistons back in the caliper without it. Some had suggested brake fluid, but that did not work for me. The assembly fluid is super slippery.

I don't recall replacing the bleeder valve, but if you had any problems getting them out I would replace them. I doing my brakes again right now and one bleeder gave me a hard time so I am replacing them this time. Lots of salt in my area so things don't last long.

As for paint I used Rust-Oleum caliper paint. I believe it said that it was a high temperature paint.
The best video for me (2 years ago many more now) was this one He is not doing a Sport Trac caliper, but you get to see the process. I also had a chipped piston so I replaced them all. I got everything from Rock Auto.

​

 

[LMHmedchem]

The pistons came out easily enough with compressed air and they look like they are in very good shape. I have not had any luck getting the piston seal boots off. I know that some versions use a snap ring to secure the boots but I don't see any sign of a ring here on the inside or outside. The boot just rips when I try to pull it off leaving the portion around the rim. It looks like the boot is permanently attached to something like a metal cup the sits in the piston socket. I can get it to move some but whatever it is will not come out.

Is anyone familiar with this type of boot? I will try to grind off some of the rubber with a Dremel so I can get a better look and post some pictures.

LMHmedchem

 

[smalltownusa]

LMHmedchemI did mine ~2 years ago. I don't recall any metal clip holding the seal in place.​

Take a look at Rock Auto they show a picture of both the inner and outer seal.

 

[CDW6212R]

Installing the seals can be very tedious, PITA. Do it when you are not rushed, and comfortable sitting down. Go slow and a lubricant would help, plus be very patient.

I don't think any caliper seals have anything holding them in, just the seal which might have a solid tough core that goes into the groove. A nice steel pick should be able to fish it out enough to get ahold of it. Try not to scratch the caliper in the seal area.

I have only changed two sets of caliper seals, because it's fairly cheap to buy rebuilt calipers. But old calipers have a lot more wear on them than new stuff, so really old calipers you can be better to do yourself. There are common calipers you should avoid buying as rebuilt, such as 90's Mustangs. Many of those have excessive wear in the slider surfaces, making a rebuilt unit too loose, and wear pads unevenly. Old calipers, if you have them, you know their mileage and condition, I'd rebuild those if average mileage of others is 200k miles or more.

 

[LMHmedchem]

LMHmedchem I did mine ~2 years ago. I don't recall any metal clip holding the seal in place.​

Take a look at Rock Auto they show a picture of both the inner and outer seal.

This picture looks exactly like mine,

CENTRIC 14365012 Front Caliper Repair Kit

On mine, there is a raised metal lip at the edge of the hole where the piston inserts to the caliper body. The top of the boot fits over this lip, or else the metal lip is actually part of the boot. I can't really tell. The metal lip looks like it is separate from the cast iron body of the caliper (it's thin and doesn't look at all like cast iron, it's flexible, etc). It moves some if I put some pressure on it with a screwdriver. It may come out, I don't know. Again, I can't tell if the metal lip is part of the caliper, part of the boot, or a separate part.

I simply cannot get the boot off. I had to use a utility knife to cut the boot off of the metal lip and then a Dremel to get rid of the rubber that was still stuck on. It is almost like the boot was glued in or melted on. I haven't been able to get any of the interior of the boot off, meaning the part between the top of the piston socket and the lower oil seal. That rubber is very stuck to the inside of the caliper. I will try with an Exacto knife to see if I can get more of the boot off.

Most of the video I have seen just show the boot being pulled off with no issue. Some models use a spring clip that has to be removed first. If that were the case here, the replacement part would come with new clips (which they do not). Mine seem very different from the videos I have seen. As far as I know, these are the original Ford calipers.

LMHmedchem

 

[LMHmedchem]

Here is a picture,

you can see the lip of the steel cylinder sitting inside the cast iron caliper. The piece of steel goes all the way down to the rim above the oil seal. It is a cylinder that is inside the cast iron caliper and has a flange on the top where it sticks out above the cast iron by a few millimeters. I can get a screwdriver under the steel rim at the edge and it moves independently of the rest of the caliper but it won't pop out easily. I can also get a screwdriver under the steel cylinder just above the oil seal. I don't see any channel for the boot to seat in inside of the caliper. The steel looks like it goes all the way down to the lip in the cast iron just above the oil seal. The rubber boot doesn't go down quite as far as the steel. If you look at picture, you can see the thin silver colored line inside the caliper with a black band above it. This sliver line is the bottom of the steel cylinder and the black band is the rubber boot which doesn't go as deep in the hole as the steel.

It really looks like the boot and this steel cylinder are a single fused piece where the steel cylinder and boot were pressed into the caliper. I can't tell how the steel cylinder is attached to the cast iron. I am not sure I can get this steel cylinder out without cutting it.

Did others see this steel cylinder when replacing the boots, or is this a different setup?

LMHmedchem

 

[smalltownusa]

Just looked at the Ford Workshop Manual for a 2005 Sport Trac. No mention of anything holding piston boot in.
Just states after removing pistons from bore "remove piston seals and boots". Boot meaning dust seal.
Be carful not to damage the bore, but isn't there an edge on the top of the boot to get under, and pry it up ?
I think the metal inside the boot is to give the boot shape so it presses the rubber (or whatever the material is) tightly against the outer wall. When you install the new one lube it, carefully tap it in place.

You may need to push the dust seal inward to deform it then pull it out.