4 piston calipers question

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fireguyfire

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I’m slowly going through the mechanicals on my survivor 67 barracuda I bought from the original owner. The car had sat in a barn for 30 years or so.
I’ve gone through the rear brakes and I’m about to get into the front disc brakes.

Are there any tips or tricks on inspecting these calipers to make sure they are good? I know replacements are hard to find so I’m going to do my best to save the originals and get them working again.
 
give a real good look to the pistons and bores for corrosion and galling. these are prone to sticking so making sure that they are top notch will ensure smooth operation. if the bores are too wasted it's possible to have them machined and bushed.

there are some parts available for rebuilds, the seals are common. but the transfer tubes are NLA and difficult to find, so be careful with those. the same goes for pistons. good used ones are around though.

know that the availability and quality of rotors can be spotty from time to time.

it's a good system when in great shape and working order.
 
I just got done rebuilding a few sets of these myself. Not a cheap process but I want to use the Kelsey Hayes as I like them. You can, at times, find rebuild calipers on Rock Auto. Which again, they are not cheap, plus there is a hefty core charge. But it costs close to the same if you buy all the parts needed to rebuild yours. Most all the parts are readily available. The Pistons are the hardest to find. But there is a little secret that some may not know. Ford used a very similar Kelsey Hayes Caliper on 65-67 Mustangs. They use the same pistons, the same rubber dust boots and rubber seals. You can google this to see what I mean.

Pistons I used are Raybestos DPS85002 and the seal kit Dorman MAS D46457.​


inlinetube.com is where you can buy pre-bent Stainless Brake lines that you most likely will need for your calipers.

Good Luck :)
 
Pits on the bores is okay (within reason) the seal rides on the piston so that area on piston has to be zit free. Use Nicop tubing for transfer lines. When taking them apart use a homemade fitting and pump grease into the calipers, that will force out the pistons.
Good luck, post your progress
 
I bought seals, pistons and tubes for these recently. SBP discs were not available but maybe now.
 
yup 4spd is correct. The seal is the rubber in the groove and piston. Bores are not as critical.When operated the piston
rolls the rubber to provide a seal and piston retraction.The pistons only move a few thou.
 
If the grease gun method doesn't work, you might try using a motorcycle caliper piston slide hammer kit. That is what I had to use after the grease gun trick didn't work.
 
hemi71x can rebuild them for you.
Probably even be cheaper in the long run.

Thats what he does, and I would trust him over the bright sign auto parts stores.
 
No disrespect to Jim, but it's not rocket science. If I can do it anyone can. Cost of shipping is stupid too.
dowboy1970 said:
hemi71x can rebuild them for you.
Probably even be cheaper in the long run.

Thats what he does, and I would trust him over the bright sign auto parts stores.
Click to expand...
 
What I am saying is sometimes the learning curve costs more than a quality finished product from another source.
Especially if it is a onetime thing.

Trust me, I am cheap as can be but sometimes its cheaper to let another do it.

Thats all I am saying.
 
Rock auto gets the pistons in stock but you have to keep checking back. Right now they are completely out. On the rebuilt caliper they usually have none or just one side and they are expensive.
Seems to be a good selection of rotors available right now.
I have rebuilt a lot of these calipers and usually the pistons all need replacing.
 
I’ve got the car in the lift and have rebuilt the rear brakes, replaced the leaking pinion seal and the U joints.
I’ll pull one of the front calipers tomorrow and post up my findings
 
be mindful of the pistons, i know there are at least two different heights. a lot of resellers don't know this and will just throw whatever in the box and roll it to you.

i'd forgotten but i think CJ ponyparts has the transfer tubes and the pistons so it's worth checking them out as well.
 
If needed, I recommend rebuilding your old calipers. Usually, anyone associated with this website would be a good place to start.
 
So a first update. I thought I would start with the drivers side and surprisingly all of the brake line fittings came free with just minor persuasion.
I have the caliper fully disassembled on the bench, and I now need to go about removing the pistons which appear to be stuck.
Someone here mentioned the grease method of removing the pistons, but my question is what is now the best method to remove the pistons from the caliper housing so I can assess the pistons and the bores?
 
I think the ford ones are the same except the output location is different.
 
I use compressed air through a rubber tipped nozle into the bleeder hole. Works for me. Put a piece of wood between piston and caliper.
 
I made a fitting with a brake hose and grease fitting to pump grease in to remove pistons. For the 4 piston caliper you will have to put clamps on the ones that are moving so the pressure can go to the other one.
I also recommend filling with brake fluid or water to minimize the amount of grease required.

Compressed air only works if the pistons are not stuck. When they are stuck you need hydraulic pressure.
 
OK, This is where one of those Motor Cycle Brake Caliper Piston Slide Hammer tool set comes in handy.

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You place one of your brake caliper halves it in a vise on a table or bench. Find the expander piece that best fits (in my set I think it was size 27?) Assemble the slide hammer set up loosely, insert the expander piece into the hollow part of the piston and tighten up the slide hammer set up.

Making sure the caliper half is securely held in your vise and the vise doesn't move, start slide hammering until it pops out. It might take a few pretty good hits to pop out but they will. It also might be kind of messy, so take that into account with some rages or whatever you choose to keep that to a minimum. Did this on several sets and it worked great.

Good luck
 
MoparMike1974 said:
I made a fitting with a brake hose and grease fitting to pump grease in to remove pistons. For the 4 piston caliper you will have to put clamps on the ones that are moving so the pressure can go to the other one.
I also recommend filling with brake fluid or water to minimize the amount of grease required.

Compressed air only works if the pistons are not stuck. When they are stuck you need hydraulic pressure.
Click to expand...
I agree with the above although I didn't worry about getting grease in the caliper. It wasn't hard to clean. Compressed air was a waste of time because I had a few badly stuck pistons. I believe the grease gun had 1/8 NPT fitting so you need to figure out an adaptor. The video shows how to use wood blocks to prevent the pistons from coming out of the bores. You will need an assortment. You never want any of the pistons to come out until they are all free (especially if you have compressed air applied).

I believe this is the video I followed

 
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I tried compressed air and nada, grease gun and POP right out. They were rusty. Psi thru grease gun is way more than compressed air. Had to use clamp as mentioned as "path of least resistance " applies.
Congrats to op on having success on the disassembly. Pistons might not be all bad.
 
I vaguely remember putting the water pump pliers on one of the pistons that was really stuck. They were around $20 ea up here.
 
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