John Lee's Power Drum Brake Conversion

[Sharps40]

As ya'll are aware. John Lee is the free replacement truck, a 1965 SBSS, (Ol John Lee was the original 64 SBSS 283 that was taken out by uninsured alien invaders in Feb of 13). John Lee is not numbers matching but close to original.

All the work being done is aimed at reliable daily driver able to keep pace with most modern traffic.

As such we've been together thru a number of rebuilds and upgrades. New I6, T5, Split dual master cylinder for safer breaks, rebuilt suspension and brakes, etc.

The newest upgrade is completed.

Peviously we detailed the conversion from single pot master to dual pot drum/drum master with the front split from the rear for safety. A great improvement in safety and driveability.

Heres the original single pot master that was on the truck when acquired in March 13.



Shortly after putting the truck on the road I lost a hose and all four brakes which accelerated the installation of the dual pot drum/drum master. We used a 1" bore dual drum manual master for a 67 C10/Impala. Under $20 for the Al Cardone from Oreillies and no weeping at the cylinders as the lil valves that prevent that from happening are in fact installed in this remanufactured master cylinder.,,,,so no external valves needed.

Details on that conversion at this link.

This post is also in the FAQ along with a similar good thread that I learned from thanks to the good folks running the board.

http://67-72chevytrucks.com/vboard/s...d.php?t=599582

[Sharps40]

As I had previously done the dual pot drum/drum master conversion on Ol John Lee, just prior to the accident, I simply transferred the master to the 1965 truck and split front from rear as detailed in the link above.

Here is what we finished with. Plenty good but somewhat a leg builder....fully manual.



Upon cracking 4 pistons on 87 octane gasoline and a suspect rebuild of that fine 68 olds 250 I had a new Oreillies 75-79 non integral intake long block installed and the Chevy Astro Van T5 trans. Acceleration was up, top speed was way up and it was a job to dog John Lee down from speed relying only on the manual master cylinder.

Comfortable with drum brakes, had em all my life and they work great if ya understand how to maintain them....I had John Lee into the shop this week for a new rear main seal.

Seems its not uncommon for crate engines to come with the inexpensive rubber rear seal, which not only drys out in storage but seems a rampant number of them come installed backwards, pumping oil out instead of pushing it back in. So...while it was in I elected to do a final brake upgrade....addition of power assist.

[Sharps40]

To the meat and taters...I contacted CaptainFab on the board and acquired one of his lovely brackets for power brake installation. Nothing like having an easy button. Tryin to keep this truck close to original but highway ready with the minimum number of new holes...cause down the line when I'm dead someone will thank the Truck gods that the PO didn't hack too much on a mostly original and fine condition rig.

The bracket came in. I ordered it in raw steel. And, it is perfect......no need to pierce the firewall with additional holes that some poor dude will just have to fill later when trying to bring this old boy back to Concours status in 2093.

All the parts, and some advice on parts is included below, bolted up easy...a simple sleeve to connect to the booster....and the only mod is to the booster and brake push rod....neither are difficult and neither should cause a future Concours minded restorer to have heart palpitations.

So, all I can say is, get it on the board. I'll be back to Captainfab in the future for whatever he makes that I might need.

[Sharps40]

In the picture below you see the final install, less a bit of paint. Looking good, functioning perfectly.

1967 C10/Impala dual resevour manual drum drum master. (1" bore)

1967 C10 Booster, 10.75" diameter.


And tucked in right behind that lovely new power booster is Captainfab's easy button for power brakes.

From the top.....the bracket bolted to the firewall using the original two holes for the single or dual pot masters. No hacking the firewall. Lovely. A kiss of


From the drivers side...the new Al Cardone booster from Oreillies bolts directly to the Captainfab bracket. So far, so good, better than good. Simple!



And one more shot of the entire installation....looks like it belongs there and durn solid. Should outlast my foot I'm sure.

[Sharps40]

Now. To insure I had the right length intermediate push rod, the one that go's between the booster and the master I had intended to purchase this assembly from Oreillies.

A complete matched set, part number 50-3715, Al Cardone, 1967 C10 Truck.

But its no longer available fully assembled. It is now an R&R part. Which means? You remove your complete assembly, send it in and they rebuild and send it back to you.

[Sharps40]

So what to do?

As discussed with Captainfab, the manual drum drum 1" bore deep well piston master cylinder is the same as that used on the power drum drum master assembly above.....hmmmm, I already have the master......

Yes, the booster with proper long intermediate pushrod is still available from Oreillies/Al Cardone. Part number 54-73709. So, we bought it. I had to eat the core since I didn't have a booster to trade in but.......you go with whatcha got.

Here is the booster we used.

[Sharps40]

Install the painted bracket to the firewall.

Install the booster to the bracket.

Install the master to the booster...guess what? We didn't have to even crack a line, no pressure bleading the brakes .... just bolt it all together. Nice....so far, better than good.

[Sharps40]

Tee off the MANIFOLD vacuum to the PCV valve and attach to the port on the new booster.

[Sharps40]

But...theres that crazy lil loop on the brake push rod of the new booster.

And with the differences between 1967 and addition of the bracket, the loop won't reach the pedal to be bolted up....

What to do?

Well, saw off the loop on the input rod to the booster.

[Sharps40]

Then, make up a sleeve and add it to the end of the original 1965 adjustable brake pedal push rod.

Upon ensuring we had the rods properly set for length, leaving room to adjust the push rod longer or shorter as the factory intended in 1965, we welded a sleeve to the end of the original 1965 adjustable push rod.

The sleeve was tapped for a locking bolt. Slip the sleeve over the input shaft of the booster, tighten the locking bolt.

Adjust for proper pedal free travel....go ride!

Here are the pics, easier to see than to describe.

At the bottom, the original adjustable pushrod bolts to the pedal. On the top, the sleeve joins the push rod to the sawed off input shaft of the new brake booster.



A closer shot of the mating of pedal to booster.

[Sharps40]

And how does it work?

Well its power brakes. The pedal feels soft for 1/2 stroke but its slowing the truck nicely.

Then boy howdy, it firms up and stops. It can stop with a vengeance. The back end of our trucks is light, light light. The rear can lock pretty easy...but ya get used to it soon enough and yer not lockin em out back anymore.

I think I'll drive it a few weeks as is and if I can't get used to it we'll try two things.

Drill the brake pedal about an inch lower and reposition the push rod....that should change the geometry a bit, and perphaps prevent the brakes from comeing on so aggressively at mid pedal.

Or, perhaps also install a disc brake style proportioning valve and dial down some of the power to the back end. I think this might be a better solution and more tunable over the long run.

But for now? I'm just pretty happy that I dog the ol boy down safely and efficiently with my toes instead of my foot and calf and leg and hips and standin up hangin on to the steering wheel.

The feel is totally different. Effortless comes to mind.

[Sharps40]

Thanks Captainfab for a fantastic product and all the instruction/advice that comes with the items you provide here on the board! Couldn't have done it as well and easily with out your engagement.

[TJ's Chevy]

Been considering converting to power.....I think I will now. lol. Thanks for the helpful info!

[Sharps40]

Yer welcome. In 30 minutes ye'll be upgrading to blue dot tail lamp lenses....they add 50 horsepower ya know. Stand by.

[TJ's Chevy]

Originally Posted by Sharps40

Yer welcome. In 30 minutes ye'll be upgrading to blue dot tail lamp lenses....they add 50 horsepower ya know. Stand by.

Well I was gonna upgrade to the CHROME Blue dot tailamps....they add 100 hp.....

[Sharps40]

Dayum! I gotta get some chrome spray paint fer my buckets, that ought be good for 2 mpg if not a bit of horses too!

[TJ's Chevy]

Originally Posted by Sharps40

Dayum! I gotta get some chrome spray paint fer my buckets, that ought be good for 2 mpg if not a bit of horses too!

Make sure you buy the chrome tail lamp holders as well....they add 120 hp...

[Sharps40]

GoleDayum he hollered! That's the ticket!

[Sharps40]

I usually run my drum breaks a bit tight. Been a while since I adjusted em and since we didn't have to crack lines for this install....I think a simple adjustment is in order.

In the morning I'll check and adjust the fronts, they should get most of the work and do the same with the rears running them a touch looser than I normally do.

We'll see how it goes and if it helps a bit with them grabbing out back first.

See ya tomorrow.

[Sharps40]

Very happy to report....all the sensitivity in the new power brakes is GONE.

Had a few good PMs with Captainfab last evening. He does good, keeps it simple enough even I can understand what to do.

Got up this AM.,...paid all the bills (so's I'd have an excuse to go ride around and buy stamps)....coffeed up and hit the garage.

Been over 6 months of steady drivin since I last adjusted the brake shoes.....normally do this on all for during the tire rotation every second oil change.

Naturally, they were a bit loose, specially the fronts where mosta the work is done. They was grabby with power cause the rears were comein on first and the fronts weren't workin hard as they should.

So....15 minutes to pull up both front shoe sets and inspect the cylinders, etc....all was well. I knew they was over loose since I slid the drums right off (I previously popped out the rivets so I can work front brakes w/o pullin the spindles). So, brought em in close for a bit of drag. (bout half a wheel spin when reassembled).

Went driving, 90% better.

Came back, tweaked the rear brakes, went drivin....very nice.

Came back, popped off the brake pedal push rod....adjusted it from 1/2" free travel to just a touch over 2/10" free travel. Went driving, pushin 99% on the brakes now.

Still effortless but more action in the top third of the stroke and no lockin the rears less ya panic stop cause ya suddenly realized, that's McDonalds on the right an I needa hashbrown eggieweggie sammie.

So....thanks again to Captainfab for the parts, advice and electronic helping hand.

This here job is almost done. Next week I'll drill the brake pedal mounting point 1" lower and reset the push rod just to see how that makes the set up feel. But really, unless its lots better I'm good and happy with the power brake conversion as it sits right here and now.

[KJSR]

Here's a good reference for brake pedal ratios....

pedalratio.pdf

[aggie91]

Thanks, another good write up for you. I did a bit of checking on costs for the parts on RockAuto.com.

They still have the booster/master combo available from A1 Cardone for the part number you have listed:
A-1 CARDONE Part # 503715 Reman. A-1 CARDONE Vacuum Power Brake Booster w/Master Cylinder

Price:$117.79 + Core:$31.50 = Total: $149.29

Just the booster is:
A-1 CARDONE Part # 5473709 Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

Price:$63.79 + Core:$20.00 = Total: $83.79

Master Cylinder is:
BENDIX Part # 11329 New Master Cylinder
Front drum brake 11" x 2 3/4"; Front drum brake 11" x 2"

Price:$36.99 + Core:$0.00 = Total: $36.99

or:
A-1 CARDONE Part # 101329 Reman. w/ Reservoir

Price:$19.56 + Core:$20.00 = Total: $39.56

Based on this, you could save a bit of cash buying the booster and master separately: $83.79 + $39.56 = $123.35 for the A1 Cardone parts...

Again Great write up and discussion of what you did once the parts are installed to get the most out of the setup.

[Indian113]

Have to tell you that your step by step write ups have HELPED me a LOT!! Your pictures and descriptions with explanations I can understand just Blows me away. Thanks Sharps

[Sharps40]

Very cool. Glad it helps fellas. Bow Ties Forever!!

[shok]

Nice write up, you are making me want to get back on the truck after being sidelined with a new project.