need help removing KH pistons

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CUDAGUY

CUDAGUY

aka Prince Valiant
Joined
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So far I have gotten three of the eight pistons out to rebuild my Kelsy-Hayes calipers for my wagon but the other five are being very stubborn.

anyone have any tips to remove these? Im ready to start swapping the discs and 8.75 in but cannot untill these are rebuilt.
 
I'd soak them down with good pentrating spray like JB-80. Shoot some into the fluid hole to get some behind the piston too. Then push air into the line. Have a block of wood in the caliper to keep the piston from flying out.
 
I have heard that you can take the caliper off off with the hose attached and stomp the brake pedal to push them out. It appears though if you have three out already this wont work. If you are going to replace all the seals and rubber why can't you heat the caliper body to expand it thereby loosening the pistons.
 
I have never to this day found a piston so stuck that 250 PSI shop air would not blow it out. I built my first caliper probably in 1978 when I was 13. Been doin it ever since so that's a lot of calipers.
 
Split the caliper drill and tap it and run a bolt in the piston to push it out. Warning I have never tried this but looking at one I think it may work.
 
caferacerx said:
rockauto has remanufactured raybestos calipers for $61.79 each after core exchange
http://www.rockauto.com/catalog/raframecatalog.php
Click to expand...

Also, Raybestos has Pro Grade fully remanufactured + guaranteed calipers with all hardware and new pads for $94, BEFORE you use the Rock Auto discount coupon code.

Seems like a great deal to me...new remanufactured calipers with pads and a very good guarantee for $94...BEFORE you apply the Rock auto discount code.

You probably will not be able to buy all the rebuild pieces (seals, pistons(if required), etc. and add new pads and hardware for much less than that.
 
CUDAGUY said:
So far I have gotten three of the eight pistons out to rebuild my Kelsy-Hayes calipers for my wagon but the other five are being very stubborn.

anyone have any tips to remove these? Im ready to start swapping the discs and 8.75 in but cannot untill these are rebuilt.
Click to expand...

I threw my calipers in a bucket of diesel for a bout 6 months. They came apart pretty good. Compressed air through the bleeder or brake line helps pop the pistons out.Your usual blower may be restricted to about 30 psi. Not enough so I built a blowtool out of a hollow pushrod and an air fitting. You may need 80 -90 or over to pop that piston out.

If they are stuck; there is a groove at the top of the piston meant for the dust boot lip. Use 2 wide tip pry bars and gently rock the piston out of it's bore while prying up on both bars.. Lots of pb blaster helped. I mounted my caliper in a vise to do this operation. There are some pics on my restoration thread.


They can be a real bear.
 
Vs29H1B said:
Also, Raybestos has Pro Grade fully remanufactured + guaranteed calipers with all hardware and new pads for $94, BEFORE you use the Rock Auto discount coupon code.

Seems like a great deal to me...new remanufactured calipers with pads and a very good guarantee for $94...BEFORE you apply the Rock auto discount code.

You probably will not be able to buy all the rebuild pieces (seals, pistons(if required), etc. and add new pads and hardware for much less than that.
Click to expand...

pads where $13
kits where $8 a side
front hoses where something like $12 each
rear hose was $15
everything else was free....with the surrender of my old wrecked ATC90

I got the three out using 120 psi compressed air and PB blaster....anyone think some vibrating water would help? I have access to a harbonic cleaner think it would work?
 
Try this. Stick the mate to the stuck one back in and C clamp it in place. Put all the air to it you got. If you got one of them blowers with the rubber tip, make it seal GOOD. Point in a safe direction. lol
 
StrokerScamp said:
Try this. Stick the mate to the stuck one back in and C clamp it in place. Put all the air to it you got. If you got one of them blowers with the rubber tip, make it seal GOOD. Point in a safe direction. lol
Click to expand...

LOL!! I've fired things across the shop not thinking about it...
 
needsaresto said:
LOL!! I've fired things across the shop not thinking about it...
Click to expand...

Ha! I got that beat BAD. I've held the caliper in my hand with my fingers between the caliper and the piston and let her rip. LMAO Talk about pain. Some things are best learned the hard way. That way you only do them ONCE. LOL!!!!!
 
CUDAGUY.
There is a very easy and safe way to get those pistons out of their bores when they are stuck.
You pump them out hydraulically with a grease gun. You need to put a grease zerk fitting into an old flare nut fitting, block off the other threaded brake line hole in the caliper half with a bolt, limit the travel of the pistons in the jaws of a vice, or use two C clamps, as the pistons never come out evenly, and hook up the end of the grease gun, and pump away. The pistons come out with pressure, as the grease forces the pistons out.
I am a rebuilder of the old Mopar brake, suspension, front end, components, and haven't had one yet that i couldn't get out with hydraulic pressure.
I will tell you what. Give me a phone call in the evening hours sometime, and i will walk you through it, and tell you what you need to do, and how it's done.
916 852-1758
Jim V.
 
StrokerScamp said:
Ha! I got that beat BAD. I've held the caliper in my hand with my fingers between the caliper and the piston and let her rip. LMAO Talk about pain. Some things are best learned the hard way. That way you only do them ONCE. LOL!!!!!
Click to expand...


I stand ashamed..Lol!

Whats really fun is to take those little studs for a body stud welder and stick em in the end of your blow gun.

I swear I can just about bombard the middle east!

Sends co-workers running for cover..
 
StrokerScamp said:
Try this. Stick the mate to the stuck one back in and C clamp it in place. Put all the air to it you got. If you got one of them blowers with the rubber tip, make it seal GOOD. Point in a safe direction. lol
Click to expand...
thats what I did on the first three...lol


hemi71x said:
CUDAGUY.
There is a very easy and safe way to get those pistons out of their bores when they are stuck.
You pump them out hydraulically with a grease gun. You need to put a grease zerk fitting into an old flare nut fitting, block off the other threaded brake line hole in the caliper half with a bolt, limit the travel of the pistons in the jaws of a vice, or use two C clamps, as the pistons never come out evenly, and hook up the end of the grease gun, and pump away. The pistons come out with pressure, as the grease forces the pistons out.
I am a rebuilder of the old Mopar brake, suspension, front end, components, and haven't had one yet that i couldn't get out with hydraulic pressure.
I will tell you what. Give me a phone call in the evening hours sometime, and i will walk you through it, and tell you what you need to do, and how it's done.
916 852-1758
Jim V.
Click to expand...

good idea, I will have to give it a try tomorrow....I wont bug you tho, it seems pretty strait forward
 
Drill & tap the end of a 3/8-24 bolt & screw in a 1/4-28 grease fitting.Screw this into the caliper body just snugging it down.
Plug the other hole(s) with bleeder screw(s), attach a hand gun, and pump away. If one moves and the other one doesn't, which it probably will, clean it up, reinstall & clamp it, then pump the other one out. Messy, but effective!
 
I had a master cylinder that would not come apart and put an air fitting with adapters in the end. Hooked up shop air to the fitting and it took days to find all the pieces on the other side of the shop. If you try this dont put anything in front of it and wear safety glasses. Brake fluid in the eyes burns.
 
hemi71x said:
CUDAGUY.
There is a very easy and safe way to get those pistons out of their bores when they are stuck.
You pump them out hydraulically with a grease gun. You need to put a grease zerk fitting into an old flare nut fitting, block off the other threaded brake line hole in the caliper half with a bolt, limit the travel of the pistons in the jaws of a vice, or use two C clamps, as the pistons never come out evenly, and hook up the end of the grease gun, and pump away. The pistons come out with pressure, as the grease forces the pistons out.
I am a rebuilder of the old Mopar brake, suspension, front end, components, and haven't had one yet that i couldn't get out with hydraulic pressure.
I will tell you what. Give me a phone call in the evening hours sometime, and i will walk you through it, and tell you what you need to do, and how it's done.
916 852-1758
Jim V.
Click to expand...

Yeah that's a good idea. And you oughtta know as much stuff as you rebuild and sell. I like the looks of your Ebay stuff. Real nice. Wish I could afford it. Not sayin it's too much.....just that I'm that broke. LOL I have to rebuild my own stuff. You do nice work.
 
Soaked mine with Kroil around the seal and used an inside pipe wrench( a tapered dodad with fine threads that extends hardened steel bars, an easy out for pipe nipples)
 
I like danger ... So I used comp air! But I had the caliper in a vise and the piston merely came out and smacked the vise not me.

This the second caliper I've taken aprt this week. I must say that comp air only worked for 1 of the 4 on this caliper.. There were no truly seized pistons,just stuck a bit.
 
StrokerScamp said:
Yeah that's a good idea. And you oughtta know as much stuff as you rebuild and sell. I like the looks of your Ebay stuff. Real nice. Wish I could afford it. Not sayin it's too much.....just that I'm that broke. LOL I have to rebuild my own stuff. You do nice work.
Click to expand...

StrokerScamp
Thank you for that comment.
It was nice to read, when i turned on my computer this morning.
Appreciate the nice words.
Jim V.
 
hemi71x said:
StrokerScamp
Thank you for that comment.
It was nice to read, when i turned on my computer this morning.
Appreciate the nice words.
Jim V.
Click to expand...

Well it's true. I know you receive a lot of crap about your prices too. People don't take into account what it takes to get the stuff in the condition that you offer for sale. It's a lotta work. And it ain't like this stuff is growin on trees anymore either.
 
I had the same problem getting all the pistons out. One would come out using compressed air but not the other until I reinstalled the one that came out and used a c-clamp to hold it. I then used the air again on & off several times till it popped out. After I cleaned everything up I realized I could have bought rebuilt ones much cheaper and with a lot less hassle.
 
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