Switching to Kelsey Hayes setup

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71duster06

71duster06

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Well, I now have everything for my disc brake upgrade except the Master Cylinder today, which should be in this afternoon. I currently have the stock drum brake setup that was completely replaced with new parts when I restored the car 5 years ago. I bought a Kelsey Hayes disc brake setup a month ago (from a member of this forum) that needed to be gone through and freshened up. I have new bearings, seals, rotors from RockAuto, stainless steel calipers from Calipersonline, and the master cylinder is coming from NAPA. I will post pics of how the setup currently looks and update as the parts get cleaned and painted. Now I can use my 340 and not be as afraid of stopping quickly. Stay tuned...
 
71duster06 said:
Well, I now have everything for my disc brake upgrade except the Master Cylinder today, which should be in this afternoon. I currently have the stock drum brake setup that was completely replaced with new parts when I restored the car 5 years ago. I bought a Kelsey Hayes disc brake setup a month ago (from a member of this forum) that needed to be gone through and freshened up. I have new bearings, seals, rotors from RockAuto, stainless steel calipers from Calipersonline, and the master cylinder is coming from NAPA. I will post pics of how the setup currently looks and update as the parts get cleaned and painted. Now I can use my 340 and not be as afraid of stopping quickly. Stay tuned...
Click to expand...

Looking forward to your documentary.

You will luv the brake stopping power improvement.

Just be certain that you have the correct rear drum brake wheel cylinders, because your proportioning valve will only work properly with the correct rear wheel cylinders. You will need the rear wheel cylinders for the factory disc/drum setup, which were used on the 1965-72 8.75" rear with 1.75" rear brake setup, standard on 1968 - 72 factory 340 Abodies.

If you install the wrong rear drum wheel cylinder, what happens is the rear tends to lockup when you apply moderate brake pedal pressure.
 
Vs29H1B said:
Looking forward to your documentary.

You will luv the brake stopping power improvement.

Just be certain that you have the correct rear drum brake wheel cylinders, because your proportioning valve will only work properly with the correct rear wheel cylinders. You will need the rear wheel cylinders for the factory disc/drum setup, which were used on the 1965-72 8.75" rear with 1.75" rear brake setup, standard on 1968 - 72 factory 340 Abodies.

If you install the wrong rear drum wheel cylinder, what happens is the rear tends to lockup when you apply moderate brake pedal pressure.
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Is there any difference between the proportioning valves of the 4-wheel drum and the disc brake one? I have looked at a few different websites and they dont specify if the wheel cylinder was used with disc or drums setups. They only say what size the drum is...
 
Calipers are painted
 

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Forgot this one. Ill start cleaning and painting the spindles/dust shields today.
 

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Looks good i will be finally starting mine in the next couple days also. Keep us updated.

As far as the wheel cylinders go i checked autozone online and they note the same wheel cylinders on the rear of the car wether it is disc or drum setup up front. AS long as they are 10in brakes.

Vs29H1B----was your problem with factory 9in rear brakes????
 
Aslo i have read before the proportioning valve is differant from the 4 wheel drum to the disc drum setup. If i understand correctly the one our cars came with is more of a distribution block since each cylinder can handle the same pressure, But it looks very similar to the correct proportioning valve. I have had trouble finding them online new probley not looking in the correct place.
 
snowmobiler7c said:
Looks good i will be finally starting mine in the next couple days also. Keep us updated.

As far as the wheel cylinders go i checked autozone online and they note the same wheel cylinders on the rear of the car wether it is disc or drum setup up front. AS long as they are 10in brakes.

Vs29H1B----was your problem with factory 9in rear brakes????
Click to expand...


The factory 8.75" rear axle setup specified the 10" x 1.75" rear brakes.

The factory 8.75" rear was factory standard equipment on all factory 340 equipped cars until 1973 when Abodies moved to the LBP.

The factory specified the 10" x 1.75" rear brakes for 1971 and 1972 340 cars, that DID NOT have the K-H discs as standard factory equipment.

The 1970 factory Duster 340 and the Dart Swinger 340 came equipped from the factory with the K-H discs and the 8.75" rear with 10" x 1.75" rear brakes which also included the correct factory proportioning valve.

The correct rear brake wheel cylinder must be used with the K-H discs to ensure that brake pressure proportioning is applied properly within the system, otherwise it is tricky to keep the rear brakes from prematurely locking up. This has been a common problem for guys that did the K-H conversions.
 
Ok. I did get the factory proportioning valve with the brake setup which I was going to use. I guess I am confused on the rear brake wheel cylinder then...What wheel cylinder am I suppose to get? Did the factory K-H setups have a smaller rear brake from the factory?
 
Vs29H1B said:
The correct rear brake wheel cylinder must be used with the K-H discs to ensure that brake pressure proportioning is applied properly within the system, otherwise it is tricky to keep the rear brakes from prematurely locking up. This has been a common problem for guys that did the K-H conversions.
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No need to change wheel cyls, prop valves, lines , or other 'voodoo'
I did this swap circa '79... on a non -power system.

Need some special tools though, ... 1 sheet metal screw & #2 phillips
screwdriver.

1) insert sheet metal screw into line seat in M/C --- REAR (closest to firewall) 2 screwdrivers & pry seat out.
2) remove spring & residual check valve
3) Replace seat ( I used an old line fitting to 'tap' the seat back in.)

25 yrs later ... completely predictable braking --- up to but not
inclusive --- a 'buck 40'

Hope this makes sense , & apologies to the board for the rambling.
 
Currently I have a non-power drum setup so I am looking for a rebuilt M/C for power disc. I assume I wont need to do anything with the springs and seats on that one correct?
 
looks good ,can't wait to hear how much of an improvement you feel you get with the K H brakes
 
71duster06,

I've been looking for new bearings and seals for my upcoming K-H disc conversion and I can't seem to find them...all I find are bearings and seals for drum-equipped vehicles.

Could you (or anybody else) provide me with the part numbers?

Thanks!
 
intergalactica said:
71duster06,

I've been looking for new bearings and seals for my upcoming K-H disc conversion and I can't seem to find them...all I find are bearings and seals for drum-equipped vehicles.

Could you (or anybody else) provide me with the part numbers?

Thanks!
Click to expand...

Parts books don't tell you wether you want stuff for disc brakes, but disc brake, and 10 inch drum brakes use all the same stuff.
These are NAPA part numbers, for what you are looking for, if you are working on the 65-72 Kelsey Hayes disc brake assembly's.
Grease Seals 17110
Inner Bearing with race BR6
Outer Bearing with race BR2
 
What about Master Cylinders. Does the M/C have to be specifically made for a A-body or can I use one from a Challenger etc. We have a few good ones at home and I would like to use one of those if they would work.
 
Before and after pics of the spindle and dust shield...been busy lately with the holliday... Getting the brake booster cleaned and painted today. New Master Cylinder is coming later this week I hope.
 

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Very nice work you're doing there ! Your work reminds me of my approach : clean and repaint everything !

The only suggestion I've got , is that you use DOT 5 Silicon brake fluid . The K-H 4 piston setup is infamous for hanging pistons up due to corrosion ( regardless of how vigilant one is with brake bleeding ) .

I'm happy to see that someone has stepped-up to the plate on K-H 4 piston brake calipres / parts for our beloved A's !
Kudos to Rock Auto !
 
LH23H2R said:
Very nice work you're doing there ! Your work reminds me of my approach : clean and repaint everything !

The only suggestion I've got , is that you use DOT 5 Silicon brake fluid . The K-H 4 piston setup is infamous for hanging pistons up due to corrosion ( regardless of how vigilant one is with brake bleeding ) .

I'm happy to see that someone has stepped-up to the plate on K-H 4 piston brake calipres / parts for our beloved A's !
Kudos to Rock Auto !
Click to expand...

I did get the stainless steel piston calipers from calipersonline.com so I hope that solves the hanging up issue
 
71duster06 said:
I did get the stainless steel piston calipers from calipersonline.com so I hope that solves the hanging up issue
Click to expand...
Stainless sleeves and-or pistons help monumentally ; however , DOT 5 is still the best choice .

Regarding power-assist brakes vs non-assist :
Matter of preference . The only qualm I've ever had with the non-assist brakes is with the way the brake pedal rides : it's at too radical of an angle .
Now a days with the adjustable push rod , I'd imagine the pedal's angle has been rectified . I do enjoy the more solid pedal feel with the assist-less brakes .

If you've got arthritis , then I'd suggest the boosted brakes :glasses7:
 
LH23H2R said:
Stainless sleeves and-or pistons help monumentally ; however , DOT 5 is still the best choice .

Regarding power-assist brakes vs non-assist :
Matter of preference . The only qualm I've ever had with the non-assist brakes is with the way the brake pedal rides : it's at too radical of an angle .
Now a days with the adjustable push rod , I'd imagine the pedal's angle has been rectified . I do enjoy the more solid pedal feel with the assist-less brakes .

If you've got arthritis , then I'd suggest the boosted brakes :glasses7:
Click to expand...

I hope I dont have arthritis...im only 23 though I do have a brand new ACL due to tearing it in football almost 2 years ago... does the pushrod need to be replaced in order to be adjustable? I have manual drums right now and the braking effort never seemed to bad to me....just didnt have the ability to stop like discs...
 
Well...I have made a little progress this week. (Been busy with work and wedding stuff) The Master cylinder is going on tomorrow, as well as the new proportioning valve, drivers side spindle, then rotors/hubs.
 

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