Kelsey Hayes rotors

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76Scamp

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I recently acquired a 1972 Dart that has the 4-piston Kelsey Hayes brakes. I'm wondering where I can get replacement rotors. Everything I've seen online is for the slightly older style with a separate hub that the rotor attaches to. This car has unicast rotors; no removable hub. Do replacements exist? Or am I just going to have to get the ones on the car turned? Thank you.
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are those big bolt or small bolt?

i know that there's uni-cast stuff out there for big bolt, and there was some a long time ago for small bolt (i think goodmark made or sold them?) but i haven't seen those in years and years.
 
In the meantime, unless they are damaged, use them. If you take them off, one side can be cleaned of rust on a flat surface with fine sandpaper or cloth. The process of flattening and resurfacing this way is called lapping. The hat side will have to be done with a block.
The rubber & grit 'rust erasor' might work too. Don't be too aggressive with that or might remvoe metal and then the surface won't be flat. Probably OK doing by hand. I've used them for other things but not rotors.
 
are those big bolt or small bolt?

i know that there's uni-cast stuff out there for big bolt, and there was some a long time ago for small bolt (i think goodmark made or sold them?) but i haven't seen those in years and years.
They are small bolt pattern. But after looking closer, this is either a really old conversion, or someone made different rotors fit. The center of both front wheels has been opened up (poorly) to accommodate the hub. Looking in the unused holes in the rotor, it was meant for something else, and someone redrilled them for this.
 
Yes, you can get replacement K-H rotors, but I guess you would need the hubs, too. Cleaning them up seems like a good plan. I suppose you should mic them first to make sure they have plenty of meat.
 
They are small bolt pattern. But after looking closer, this is either a really old conversion, or someone made different rotors fit. The center of both front wheels has been opened up (poorly) to accommodate the hub. Looking in the unused holes in the rotor, it was meant for something else, and someone redrilled them for this.
interesting... probably some ford parts that were modified to fit, hence the opening of the wheel register. for a long time the KH rotors were near impossible to get so a lot of people went to great lengths making thing just work.

like others have said, i'd try and clean up what you have and then make a plan from there. it's possible there's still life in there, but be ready to scrap it all and have a contingency plan in place.
 
I sold a set of SSBC brakes that came as a kit a while back, and it had those rotors on it. They are Mustang rotors for like 67-68 or along there. Take a look at the caliper mounting brackets. If they are a piece of flat plate bolted to the spindle, that may be an SSBC conversion kit. If so, there will be an adapter ring behind the seal on the backside of the rotors.

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I sold a set of SSBC brakes that came as a kit a while back, and it had those rotors on it. They are Mustang rotors for like 67-68 or along there. Take a look at the caliper mounting brackets. If they are a piece of flat plate bolted to the spindle, that may be an SSBC conversion kit. If so, there will be an adapter ring behind the seal on the backside of the rotors.

View attachment 1716270099View attachment 1716270102
That looks exactly like what is on this car. So, it's all Mustang parts? Was there a thin wheel spacer that was part of that? There's an 1/8" spacer, I guess to make the wheel clear the caliper. And like I said, the center of the front wheels has been hacked out, but they appear to run true. I believe there is still one Volare left in the junkyard near me, so I think I'll grab the spindles from that and just convert this car to big bolt pattern. It'll just make life easier. I need to rebuild the front end anyway. It has an 8 3/4, and axles for that are fairly cheap.
 
That looks exactly like what is on this car. So, it's all Mustang parts? Was there a thin wheel spacer that was part of that? There's an 1/8" spacer, I guess to make the wheel clear the caliper. And like I said, the center of the front wheels has been hacked out, but they appear to run true. I believe there is still one Volare left in the junkyard near me, so I think I'll grab the spindles from that and just convert this car to big bolt pattern. It'll just make life easier. I need to rebuild the front end anyway. It has an 8 3/4, and axles for that are fairly cheap.
I just bought that setup at a swap meet, then changed my mind about using it because I stumbled on a 73 and up big bolt pattern A body setup. The only spacer I saw was the one behind the rear seal for the back bearing. The SSBC brakes are a bolt on kit for A body Mopars like your 72 Dart. They bolt right on to factory 10" drum brake spindles. The calipers are the same thing as what would have came on your Dart, had it come with factory disc brakes. Mopar small bolt pattern rotors are 2 piece, but the Mustang rotors are one piece and have the slots in the side of the hub. You could move the wheel studs out to the 4.5 bolt pattern holes if you wanted. Look on your calipers and see if they have SSBC cast into the caliper body like the one in the pic below. If they don't, they are probably factory Mopar calipers. If your upper control arms have the small upper ball joint, it's more than likely an SSBC conversion. If you do decide to grab the Volare/Aspen disc setup, you will need some 73 and up, upper control arms that use the big ball joint because the F body spindle needs that ball joint instead of the small one. FABO member @blewbyu lives in FL, and had some factory BBP disc setup cores for sale a while back, so maybe contact him to see if has any left.
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I just bought that setup at a swap meet, then changed my mind about using it because I stumbled on a 73 and up big bolt pattern A body setup. The only spacer I saw was the one behind the rear seal for the back bearing. The SSBC brakes are a bolt on kit for A body Mopars like your 72 Dart. They bolt right on to factory 10" drum brake spindles. The calipers are the same thing as what would have came on your Dart, had it come with factory disc brakes. Mopar small bolt pattern rotors are 2 piece, but the Mustang rotors are one piece and have the slots in the side of the hub. You could move the wheel studs out to the 4.5 bolt pattern holes if you wanted. Look on your calipers and see if they have SSBC cast into the caliper body like the one in the pic below. If they don't, they are probably factory Mopar calipers. If your upper control arms have the small upper ball joint, it's more than likely an SSBC conversion. If you do decide to grab the Volare/Aspen disc setup, you will need some 73 and up, upper control arms that use the big ball joint because the F body spindle needs that ball joint instead of the small one. FABO member @blewbyu lives in FL, and had some factory BBP disc setup cores for sale a while back, so maybe contact him to see if has any left.
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I will look at that tomorrow. I am aware of what's needed for the Volare spindle swap. I did it on my 74 Dart Sport. Like I said, the front end needs rebuilt anyway, so I'll just buy new control arms; they are readily available on Summit. The problem I see with this, is if I were to need replacement rotors, there's not a machine shop within 100 miles of me that can redrill them. Kinda the same issue with the Scarebird kit I was looking at; it bolts on, but the rotors have to be drilled, and no one around here can do that.
 
I'm with you on that! I'd rather be able to just get rotors at NAPA or O'Reilly's than have to fiddle with them to make them work. The taller spindles from F bodies help with alignment too.
 
Well @JDMopar seems to be right, this is an old SSBC kit. Hard to tell through all of the dirt and paint, but it is there on the calipers. Thankfully, they do still sell parts for it. Expensive, but parts exist. I guess I'm down to pricing out which is the least expensive: convert the car to big bolt pattern, having to buy axles for the rear, and use later brakes up front while also having to change the wheels, or buy replacement parts for what I have.

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If you need to rebuild those existing calipers, @hemi71x might be able to give you some tips on how to do it and where to find parts. They are the same as what would have come on that car. If you want me to add all of the pics I still have of the ones I sold to this thread, I'll be glad to. Maybe it would help you see how to get them apart before you start digging thru all the crud. They must have worked fine for a long time, cause they look "Experienced" lol.
 
As we speak, i am in the rebuilding process of a Kelsey Hayes, 4 piston caliper, disc brake system that i purchased at a Mopar show, and swap meet, two weeks ago.
These KH brake systems are now pretty expensive to do rebuilding on.
Caliper replacement pistons are out of stock at Rock Auto, and i got the very last ones that Summit had.
Had to go thru the Ford Mustang, restoration parts selling companies, that sell these parts.
And they aren't cheap.
One company wants $25.00 bucks a piston, which is ridiculous for a price.
But i found some at $17.50 each. But still OUCH.
I purchased a total of 8 calipers at the swap meet, for me to do my thing with.
As far as rotors go, Rock Auto still has them in stock at $25.00 bucks, each.
I got 2 of them yesterday.
Getting pistons out, it's easy for me, as i have the official Miller Special Tools, from back in the dinosaur days.
But stuck pistons can also be pumped out hydraulically using a grease gun, using grease pressure to get them out.
I just put a grease fitting into a hydraulic line fitting, to pump grease into the caliper body.
Then i but the half of the caliper behind the jaws of a vice, to limit the travel of a caliper piston if one want's to come out of it's bore quicker than the other one.
But a mechanic with any type of repair procedures under his belt can figure it all out.

Rock Auto rotors.
More Information for CENTRIC 12163005

MILLER SPECIAL CALIPER TOOL 001 (Small).JPG
 
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If you need to rebuild those existing calipers, @hemi71x might be able to give you some tips on how to do it and where to find parts. They are the same as what would have come on that car. If you want me to add all of the pics I still have of the ones I sold to this thread, I'll be glad to. Maybe it would help you see how to get them apart before you start digging thru all the crud. They must have worked fine for a long time, cause they look "Experienced" lol.

As we speak, i am in the rebuilding process of a Kelsey Hayes, 4 piston caliper, disc brake system that i purchased at a Mopar show, and swap meet, two weeks ago.
These KH brake systems are now pretty expensive to do rebuilding on.
Caliper replacement pistons are out of stock at Rock Auto, and i got the very last ones that Summit had.
Had to go thru the Ford Mustang, restoration parts selling companies, that sell these parts.
And they aren't cheap.
One company wants $25.00 bucks a piston, which is ridiculous for a price.
But i found some at $17.50 each. But still OUCH.
I purchased a total of 8 calipers at the swap meet, for me to do my thing with.
As far as rotors go, Rock Auto still has them in stock at $25.00 bucks, each.
I got 2 of them yesterday.
Getting pistons out, it's easy for me, as i have the official Miller Special Tools, from back in the dinosaur days.
But stuck pistons can also be pumped out hydraulically using a grease gun, using grease pressure to get them out.
I just put a grease fitting into a hydraulic line fitting, to pump grease into the caliper body.
Then i but the half of the caliper behind the jaws of a vice, to limit the travel of a caliper piston if one want's to come out of it's bore quicker than the other one.
But a mechanic with any type of repair procedures under his belt can figure it all out.

Rock Auto rotors.
More Information for CENTRIC 12163005
I have no intentions of rebuild the calipers on the car. New, or reman replacement calipers are readily available for relatively cheap. About $85 with a $20 core each, or $86 each for new ones from Rockauto. The rotors have been the complicated part the whole time, but it appears SSBC still sells them; for $192 each.
 
When all else fails when trying to get the pistons out of Kelsey/Hayes calipers. Drill a hole in the piston for a 5/16 tap. Then you can thread a bolt into the threads you made and push the piston out. The pistons are pretty thick, around 1/4 inch, or more.
If the piston isn't in too bad a shape you can weld the hole up, and smooth, and finish it out.

I had 4 sets of pistons made for me in a machine shop I worked in, at one time. Can't get them their anymore. They can be made on a lathe easily.

Dave
 
When all else fails when trying to get the pistons out of Kelsey/Hayes calipers. Drill a hole in the piston for a 5/16 tap. Then you can thread a bolt into the threads you made and push the piston out.
If the piston isn't in too bad a shape you can weld the hole up, and smooth, and finish it out.
I had 4 sets of pistons made for me in a machine shop I worked in, at one time. Can't get them their anymore. They can be made on a lathe easily.

Dave
You DON'T have to do any type of drilling at all.
Your throwing out lots of miss information there, in such a method that you described.
In being around cars, and auto repair, for the past 55+ years, i NEVER have heard of your method of removing a caliper piston(s) out of a caliper body itself.
But that's a new one on me, that's for sure.
Read post #18 how i replied with getting stuck pistons out of their bores by just using a hard line fitting with a grease fitting in it.
Just screw the hard line tube fitting into the caliper body. That's all that you have to do.
Easy Peasy.

And this is how ya do it, on the main, big body of the KH caliper, using a 3" x 3" block of wood, in the bench vise.
Just keep opening the vise jaws as the pistons begin to come out equally, while pumping away on your grease gun.

Grease Fitting in KH Caliper 002 (Small).JPG


Piston Removal KH Calipers 001 (Small).JPG
 
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As we speak, i am in the rebuilding process of a Kelsey Hayes, 4 piston caliper, disc brake system that i purchased at a Mopar show, and swap meet, two weeks ago.
These KH brake systems are now pretty expensive to do rebuilding on.
Caliper replacement pistons are out of stock at Rock Auto, and i got the very last ones that Summit had.
Had to go thru the Ford Mustang, restoration parts selling companies, that sell these parts.
And they aren't cheap.
One company wants $25.00 bucks a piston, which is ridiculous for a price.
But i found some at $17.50 each. But still OUCH.
I purchased a total of 8 calipers at the swap meet, for me to do my thing with.
As far as rotors go, Rock Auto still has them in stock at $25.00 bucks, each.
I got 2 of them yesterday.
Getting pistons out, it's easy for me, as i have the official Miller Special Tools, from back in the dinosaur days.
But stuck pistons can also be pumped out hydraulically using a grease gun, using grease pressure to get them out.
I just put a grease fitting into a hydraulic line fitting, to pump grease into the caliper body.
Then i but the half of the caliper behind the jaws of a vice, to limit the travel of a caliper piston if one want's to come out of it's bore quicker than the other one.
But a mechanic with any type of repair procedures under his belt can figure it all out.

Rock Auto rotors.
More Information for CENTRIC 12163005

View attachment 1716270618

Hemi71x, Those Centric rotors looked to have cast hats instead of machined. Much better chance on not rubbing the piston seals than the machined hat rotors. I just may get a pair of those for the hubs I found at the Cupertino show. Bob
 
Hemi71x, Those Centric rotors looked to have cast hats instead of machined. Much better chance on not rubbing the piston seals than the machined hat rotors. I just may get a pair of those for the hubs I found at the Cupertino show. Bob
Well, i guess i never had a machined hat, and then a cast hat, side by side, to make a determination, and comparison.

But i will tell you this, that nobody has ever given me any kind of negative feedback, on the rotor type that i have sold with my complete rebuilt set ups.

I'm currently working on, doing the rebuilding on, the current set that i have.

The rebuild kits are taking their time getting here, to me.

EDIT:
The pair of new rotors that i currently have, are with a machined hat.
 
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Well, i guess i never had a machined hat, and then a cast hat, side by side, to make a determination, and comparison.

But i will tell you this, that nobody has ever given me any kind of negative feedback, on the rotor type that i have sold with my complete rebuilt set ups.

I'm currently working on, doing the rebuilding on, the current set that i have.

The rebuild kits are taking their time getting here, to me.

Within the last 3 years, I've bought 4 pairs of new machined hat rotors, and once mounted, all rubbed the seals. Sent 3 sets back for refund and cut the last pair down on a lathe to clear the seals.

I have two pairs of used swap meet hubs with cast hat rotors. Both pairs were on their respective cars until worn passed the thickness limit, which tells me they didn't rub the seals. I just ordered a pair of the cast hat rotors shown in your link from Rock Auto, and will replace the cast hat rotors on the pair of used hub/rotors I just got at the Cupertino meet. They'll be a spare set.

The last set of machined hat rotors I bought were from Laysons and they rubbed. I took photos and sent them to Dave Layson. He said he would do his own investigation (he mounted up a set) and after doing so, agreed that they rubbed. He refunded my money and told me he was sending all of his inventory back to his supplier for replacement or modification. I am not blaming Dave Layson for this as he is not the only vendor that has this issue, and he took care of me.


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