Front and rear drum brake overhaul

[Steel Clydesdale]

Aaaannnddd....the replacement wheel cylinder doesn't fit. The housing/casting just a bit oversize.

Grrrrr. Really didn't expect this kind of problem. Guess I could grind down a little. Old one's beyond honing, there's a huge rusty patch in the bore. I expect the others will be similar.

Been too long since they were purchased, to expect to return them. Not naming names, but they came from some place in Kansas.

Well, time for some shuteye. Tomorrow will be a better day.

[stephen44]

Since you are doing a total overhaul, you may wish to consider using silicone brake fluid. I have that in all my classics and never worry about moisture or seized pistons. Brakes work perfectly everytime even after sitting long periods.

I looked into this for mine but came up with the following info

Air Solubility

Silicone fluid will absorb more air because there is more “room” between the molecules that make up the fluid. The term “dissolved air” (air absorbed from the atmosphere) should not be confused with the term “entrapped” or “free air” since their effects on brake system performance can be entirely different. Air that has been absorbed from the atmosphere does not result in an increase in fluid or system volume, whereas entrapped air or free air does occupy system volume and can be easily compressed when force is applied to the system.

Compressibility

Because of the dissolved air, silicone fluids are up to three times more compressible than glycol based fluids. This can contribute to a slightly spongy feeling brake pedal, particularly near the higher end of their temperature range but well below the dry boiling point. While this is of absolutely no consequence for normal street use, this is why silicone fluids are not used in race cars. A spongy pedal makes it difficult to modulate the brake pressure under racing conditions.


Because air bubbles do not easily dissipate in silicone brake fluid, special care must be used to prevent them from forming during pouring and bleeding operations.


The end conclusion was this all makes it very hard to bleed ? - Do you have any problems ?

[ultraranger]

In looking back through my receipts from 2 years ago, when I completely went through the brakes on my '69 F-100, I found the part numbers for the wheel cylinders that you would need for your truck. I got the parts from O'Reilly's.

Left front wheel cylinder: BHH WC18290, 1-1/8" bore, $10.64

Right front: BHH WC18291, 1-1/8" bore, $10.64

Left rear: BHH WC17507, 7/8" bore, $5.85

Right rear: BHH WC17508, 7/8" bore, $5.85

[Steel Clydesdale]

Ultraranger--thanks again. I'm thinking: just getting another set would be easier than fooling around with grinding. I double and triple checked the part numbers against their catalog but who knows, maybe that outfit in KS simply sold me some cheapo repro. Maybe one of the POs changed something. I really doubt it, though, as all the other parts seem exact.

Speaking of *PO changing something*----

The MC definitely isn't original. Fluid was leaking from the cover and first thought was "check the old gasket" and sure enough, it had a small tear. Went all over town trying to find one that fit. Even took it with me! International Harvester, anyone?

That was when I decided to start collecting parts for the inevitable major brake job. (Only drove Clyde when I had to, and on side streets, no highway, etc etc) Then, to top it off , as I drained that rear line yesterday, the rear, larger, MC reservoir level went down. So yeah, the lines are going to be different, the fittings probably too.

It just keeps getting better and better as I get into stuff--like solving a huge puzzle!!

Good thing I *like* puzzles.

[ultraranger]

"...Was a bear getting the parking brake cable out, but I managed to complete the disassembly with no other issues. "

This is after-the-fact but, here's a tip for removing the parking brake cables from the backing plate; Place a small diameter hose clamp around the barbs, where the cable locks into the hole of the drum backing plate, compress the barbs with the hose clamp then pull the cable out through the hole.

--at least you'll know next time...

[flyboy2610]

A box end wrench of appropriate diameter will work for that as well.

[Steel Clydesdale]

A box end wrench of appropriate diameter will work for that as well.

That's what I ended up using, along with a flat screwdriver to get that last pesky barb pushed in. Difficult angle & not much wiggle room! One of those 3-handed jobs for sure

The new cable felt kinda 'dry' so I ran some lock lube (graphite based) thru it. Nice and smooooth now.

*********
Edited to add:

I used a (new & clean!) ratcheting tie-down to hold the brake shoes & adjuster all together while installing the adjuster spring. Worked great!

[crazyhorse]

Mr Ranger, thank you for posting that great information.
I'm saving it to use later, ( hopefully).

[Steel Clydesdale]

I found a great tool for grasping the cable retainers: specialty modified pliers I picked up for about $5 at a cheapo tool outlet.

BTW, I resized the pic @ photobucket but it still comes out HUGE.

Here's a shot of the right rear wheel cylinder, pretty rough so it's gone:

And my tie-down trick for holding it all together while installing springs:

Finally, I learned that when using a hardware kit, it r-e-a-l-l-y helps to break the paint loose on those springs!

So yesterday was fun out in the shop!

[sargentrs]

Congrats! Btw, great trick with the tie down strap. Wish I had seen that before I did mine. I'll definitely keep that in mind on future rebuilds. Thanks!

[Steel Clydesdale]

Quick update:

First, a thanks to Tbone6 for suggesting new lines--most of Clyde's fittings are so siezed, I've had to cut steel lines just to get the hoses off their brackets.

Turns out, PO had reversed front/rear circuits from MC to the distribution block. The new lines tell a tale of where things *should go* (as well as save my bacon due to the required cutting to remove old stuff) This explains why the rear reservoir drained when the rear lines were disconnected.

Have got both rear drums/shoes/wheel cylinders/park brake cables/adjusters/hoses/hard lines replaced. Have unclamped lines along the frame rail and disconnected front hoses. Not a single drop of brake fluid from the front, yet that reservoir is full. Probably 'shut off' at the distribution block -- hope I can get the fittings out if it without destroying it! It's going to get a daily shot of PB Blaster until things loosen up.

It's been a slow project--I get one day a week to work on it & the temps have been around 100* for weeks. Can't even have a fan with all that brake dust.....

Next weekend: the front drum work and continued replacement of hard lines!

Thanks everybody for your tips and tricks--------------------

[tbone6]

[4F250s]

Thanks for the update. I'm curious how the distribution block looks when you take it out. I'm replacing my brake lines next week and would love to see some pics of how your setup looks. I also have four wheel drums.

[sargentrs]

Quick update:

First, a thanks to Tbone6 for suggesting new lines--most of Clyde's fittings are so siezed, I've had to cut steel lines just to get the hoses off their brackets.

Turns out, PO had reversed front/rear circuits from MC to the distribution block. The new lines tell a tale of where things *should go* (as well as save my bacon due to the required cutting to remove old stuff) This explains why the rear reservoir drained when the rear lines were disconnected.

Have got both rear drums/shoes/wheel cylinders/park brake cables/adjusters/hoses/hard lines replaced. Have unclamped lines along the frame rail and disconnected front hoses. Not a single drop of brake fluid from the front, yet that reservoir is full. Probably 'shut off' at the distribution block -- hope I can get the fittings out if it without destroying it! It's going to get a daily shot of PB Blaster until things loosen up.

It's been a slow project--I get one day a week to work on it & the temps have been around 100* for weeks. Can't even have a fan with all that brake dust.....

Next weekend: the front drum work and continued replacement of hard lines!

Thanks everybody for your tips and tricks--------------------

Btw, where did you get your brake lines?

[Steel Clydesdale]

4F250s wrote:
I'm curious how the distribution block looks when you take it out. I'm replacing my brake lines next week and would love to see some pics of how your setup looks. I also have four wheel drums.

4F250s: Sorry the pic is blurry, but here's the block w/plumbing labels--I've unclipped the switch connector:


I've ordered a rebuild kit, because I'll probably need it: https://www.musclecarresearch.com/valve ... drum-67-69

Sargentrs wrote:
Btw, where did you get your brake lines?

Got my new lines from http://www.inlinetube.com

Kit for this truck (Part number SFRB6702) had 8 sections & the ones I've installed so far have fit perfectly. Only one part I've needed to come up with: a 3/16" union fitting to join the 2 pieces that run from dist. block to rear axle.

Am not done yet, so............we'll see.............