How to remove rear brake caliper? 86 Chieftain 31

BrianB · November 13, 2015, 09:32 PM

Trying to figure out how to remove the brake caliper on my 1986 Chieftain 31. I have removed a bolt in the clamp on the rear side of the mount, but can't get this "clip" thing out.

Can anybody who has done this provide guidance? Attaching a picture showing the piece I think needs to come out first.....

Rickf1985 · November 14, 2015, 09:35 AM

You need to drive that piece out to the inside, or outside, either way. There is a spring steel bar between that flat piece you are looking at and the caliper that will come out with it. The you have slide the caliper up fully into the notch on top and angle the bottom out and remove. When you put this back on be sure to lubricate those sliding surfaces with high temp brake grease, NOT chassis grease. Do not get it on the rotor or pads. If you do wash it off with brake cleaner right away.

Bnova · November 14, 2015, 10:01 AM

Also, it will move more freely if you push the piston back into the caliper if you haven't already done so. I normally use a screwdriver and go in through the oval hole on back side of the caliper where if you look in that hole, you can see the rotor edge and the brake pad that is on the piston side.

There's usually enough room to get a smaller screwdriver in between the piston and the brake pad. Put the screwdriver into the piston cavity between it and the pad and work the piston back into the caliper a ways, it doesn't take much. Be really careful though, some of those pistons are made of something other than steal, like a phenolic or plastic or something like that which can break and chip. You could damage that type beyond repair if not careful when retracting the piston in this manner.

M & J · November 14, 2015, 10:12 AM

You can also use a large C clamp to compress the piston.

EldoradoBill · November 14, 2015, 07:29 PM

Quote from: M & J on November 14, 2015, 10:12 AM
You can also use a large C clamp to compress the piston.

This is the way to go, you will gouge/break/chip things with a screwdriver (which is for screws, btw) There is supposed to be a set screw holding the spring wedge from sliding out but these often break off and are missing/left off. You'll have to drive the wedge out with a punch anyway, then the caliper will lift off.

Bill

Rickf1985 · November 14, 2015, 09:39 PM

He already took the set screw out, Post number one.

BrianB · November 14, 2015, 10:48 PM

thanks guys. I beat on it quite a bit with a hammer and brass punch with no luck before I came here asking. The guy at a local RV repair place said I would probably need heat on it.

I've worked on heavy duty chassis before but never disc brakes on them. They are different than the light duty pickup style.

I am going through the entire motorhome, starting with brakes. Goal is this: http://alaska.boorman.us/

lemortede · November 14, 2015, 11:28 PM

Brian,
I feel your pain.
I did the same thing on my 88 and rebuilt the brakes from the ground up.
I was frustrated at the lack on information about the brakes and that stupid retainer.

Here is a link to a video I made.
I have been meaning to upload it and this was my motivation.
https://youtu.be/LMhqycWBRqA
Its still in the process of uploading to Youtube so give it about 90 minutes.

DaveVA78Chieftain · November 14, 2015, 11:39 PM

Join the site and download the 1986 P30 manuals for nice info like this tough not like yours. The video is though.

Front wheel Video but rear is the same

Rickf1985 · November 15, 2015, 09:40 AM

That caliper setup is exactly the same as the front brakes on most 70's-90's Ford pick ups. Ironic isn't it? GM using the same setup as Ford.

DaveVA78Chieftain · November 15, 2015, 01:03 PM

Actually, I wish they did more of that. Would make parts support greatly more reliable. Bendix designing a system that can be used on multiple chassis! Whopp'ee!

Rickf1985 · November 15, 2015, 08:28 PM

I much prefer the pin and grommet mount, It does not bind anywhere near as much as the Bendix setup.

lemortede · November 15, 2015, 11:13 PM

Oof. So I uploaded the video and didn't fix the rotation. Sorry about that. I'm fixing it now.

BrianB · November 21, 2015, 11:40 PM

It's not coming out. Ugh. Lots of heat and lots of PB Blaster penetrating oil. Still won't budge.

Tomorrow when I get my LED light back from my other place I'm going to just carefully cut it with the oxy. I plan on replacing the calipers anyway and the reman calipers come with new spring and retainer.

Rickf1985 · November 22, 2015, 10:25 AM

If you can just cut off the end of the spring and drive that out then you might be able to get some up and down movement in the slide. Torching that slide without damaging the mount will be hard to do due to the mass of the slide between the caliper and the mount.

Bnova · November 22, 2015, 10:52 AM

It might be worth a try with an air hammer and punch.

kennyrodgers · January 11, 2016, 05:08 PM

Thanks for that video lemortede.
It helped me out a whole bunch when i did my rear calipers last week. The slide plates were seized but a kept going at it with a good heavy hammer and very blunt chisel and sure enough......eventually.
Many thanks, best p30 caliper video on the net.

BrianB · January 17, 2016, 03:40 PM

Quote from: DaveVA78Chieftain on November 14, 2015, 11:39 PM
Join the site and download the 1986 P30 manuals for nice info like this tough not like yours.

I already have all the manuals on CD, but will at some point get a full membership. Thank you.

BrianB · January 17, 2016, 03:49 PM

Quote from: Rickf1985 on November 22, 2015, 10:25 AM
If you can just cut off the end of the spring and drive that out then you might be able to get some up and down movement in the slide. Torching that slide without damaging the mount will be hard to do due to the mass of the slide between the caliper and the mount.

I ended up torching them out on both sides. It was easier and less frustrating for me. No damage to the mounts on either side. I did the right-rear back in early December, and just got the left rear out yesterday. Had a break in the middle for a 3-week trip to Florida.

I also figured out how to get the hub and rotor separated. Since the chassis only has 27K original miles, the rotors are still pretty thick and just need the rust pitting cleaned up. While it's apart, I'm going to repack the bearings and put new seals in the hubs and gaskets on axle covers.

Here's everything out and on the bench:

BrianB · January 17, 2016, 03:54 PM

Right Rear hub off:

lemortede · January 17, 2016, 06:00 PM

Quote from: kennyrodgers on January 11, 2016, 05:08 PM
Thanks for that video lemortede.
It helped me out a whole bunch when i did my rear calipers last week. The slide plates were seized but a kept going at it with a good heavy hammer and very blunt chisel and sure enough......eventually.
Many thanks, best p30 caliper video on the net.

Thanks. That's why I did it. I was looking for a video that more or less showed all that and couldn't find a decent one. Glad it helped.

bluebird · January 18, 2016, 07:30 PM

I used an air chisel with one of the chisels ground flat. takes them right out. My buddy was watching me and couldn't believe how they came out. I do spray them with kryoil first though. I have more of a problem getting them back together than getting them apart.