Beemon

I've always wondered about ads like these. Do they let you take it out for a test drive first or do they just let it run and you play with the shifter? Also I'm not an expert on the subject, but I've seen tools like that before and my mother always said she took autoshop in highschool.

The only reason I suggested the bolts is because they're used to locate the drum to the hub. Modern cars with lug studs don't rivet the drums to the hub anymore because the studs help locate the drum. And piece of mind. I've heard you don't need them either, but that was from the HAMB and they do things differently over there.

This creates a vacuum leak and exposes the internal vacuum circuit to the external vacuum where the dust is. The reason why the brake pedal comes back up is because the power piston by spring force is then seated to the vacuum diaphragm and vacuum escapes from the power piston around the pushrod. If the boot seals around the power piston, it won't let the brake pedal release and it will suck the power piston down into the bore. The vacuum must flow out of the power piston and back through the vacuum diaphragm until the vacuum diaphragm seals against the top of the vacuum canister, shutting off the vacuum circuit. If you vent the vacuum from the dust boot, then you have less vacuum. In general it obviously works, but you have poorer economy due to the vented vacuum. I have yet to see a distributor sell a correct power piston dust boot.

There is no safety benefit to a dual-circuit master cylinder, in my experience that claim is a myth. I had a front rubber hose blow on my 2002 Jeep Liberty that has a dual circuit master cylinder and I had zero brakes. Dual circuit master cylinders work on the same principles as a single circuit and still require primed fluid in order for the system to work. If one system fails and drains fluid from a reservoir, then you're still pushing against air and you have zero brakes. For the logic of a dual circuit to make sense, you would need two separate, enclosed master cylinders that work in tandem with each other. That's why I scrapped the crap and put the original one back in. The newer boot I had bought was solid. Yours may work, but it may cause a vacuum leak. I don't have a vacuum bleeder so I can't comment, but I did bleed the system without a helper. I just left the bleed nut open with a piece of surgical tubing immersed in brake fluid and would do four or five pumps and check to fill the reservoir and check the bottle for bubbles. As for brake linings, the bonded ones from NAPA seem to work fine for me.

Do these items tend to brake down over time? I only ask because mine originally didn't work until I cleaned some corrosion off with scotchbrite.

That's not true, I just tried putting 65 Aluminum drums on my 56 Buick and the backing plates on the 56 interfered with the aluminum finned portion of the drum. Backing plate thickness is also different.

I literally just did this last night before going to bed, I was up until 3 am in the driveway and had the same issues as you. Before I tore into my system, it lasted 5 minutes after sitting on the shelf and I had to completely redo the inside. The brakes work great now! The issue you're having is a very large air pocket that is formed by filling the reservoir with air in the system. At the brake proportioning block, there is a rubber diaphragm check valve that keeps the fluid primed in the lines since the master cylinder is below the wheel cylinders. I started at the wheel cylinder closest to the master and attached a piece of surgical tubing to the bleed nut, which ended in a glass bottle. I opened the nut and waited until fluid began to pass and bubbles stopped coming out. I closed the bleeder and did this to all four wheels until I was the rear farthest from the master. What I then did was I kept the bleeder on the farthest open and got in the car and just started pumping the brake pedal all the way to the toe board. After 5 pumps, I would check the fluid reservoir and fill if required. It took maybe 30 minutes to get the first burp out and it was a huge air pocket. You'll know when you get close to the big bubble because the pedal gets almost ridiculously hard to go to the floor and then a sudden release in pressure as the line clears. After the large air bubble passes, and there were probably about three large bubbles, I kept bleeding the line until the foam stopped appearing. I then closed the bleeder and went to the driver rear cylinder and did the same thing. So on and so forth. When you get back to the front driver side wheel cylinder and finish pumping the fluid out, I then went back to the passenger rear cylinder and did it all over again until there were no traces of foam or bubbles in the line. It's a lot of patience, but the bubble eventually works its way out. All in all it took me an hour and a half to get the brakes properly bled. I used a large bottle of the Valvoline 3+4. I also have a 1956 Buick Century, but mines a 2 door. Also word of advice and ditch that pushrod boot. If you still have the original one, use that. Those narrow neck pushrod boots will be sucked inwards by internal vacuum of the unit and close off the power piston operation cycle. When I had a boot like that, it would create a seal around the power piston and constantly pull the brake pedal down to the applied position. When I switched back to the original boot, the booster operated as it should and I have been happy since. I initially adjusted the brakes to five clicks out on the adjuster per the shop manual but this is too much because the manual says the applied position should be an inch from the toe board and the applied position for me is almost at the toe board. So when you adjust the brakes, try to set it initially at 3-4 clicks out from their fully extended position (adjust shoes out until you can't rotate the wheel by hand then adjust back in). Hope this helps! Let me tell you I went to a modern setup and the original blows the socks off any modern system you can fit down there. The car stops like any modern car, just don't get crazy with it and downshift down the big hills.

Size and thread for the lug bolts? Or rivets? I drilled some rivets out on a 65 Riviera front hub to get the aluminum drums off with a 1/4 drill bit. Since they're not threaded, I suppose you could just put 1/4 bolts through the holes. The rivets are really just there to center the drum on the hub assembly so they don't move around and someone else can correct me if I'm wrong, but they aren't required for vehicle operation. NAPA stocks the lug bolt if that's what you're inquiring about.

You will not be able to buy any new drums with the hub assembly attached, just FYI. You will need to grind off or drill out the rivets that hold the drum to the hub and then remove and discard the old drum. Just substitute grade 8 bolts for the rivets.

Kanter CARS I'd get you a link to Classic Buicks, but their website seems to be down. For what it's worth, I've heard that all of the distributors get their drums from the same manufacturer, but their warranties are different. I've also heard drums being out of round a few thousandths out of the box and have to be turned. I've only bought drums for the rear of my 56 since I mistakenly went to discs on the front, but I haven't had issues with them at all. They're from Kanter. Ordering from a supplier will be faster than trying to locate a NOS or used set but the older stuff was made differently from the newer stuff.

The only thing it does is split the line 50/50 and supply a residual check valve so fluid doesn't seep back into the master. You can duplicate this by getting a 3/8" T fitting, a 10lb residual valve and a fitting from the MC to the residual valve (7/16"?). The 53/47% braking power comes from the different size in front and rear wheel cylinders themselves so you have nothing to worry about. Where is your valve leaking from? IIRC it's tightened with a copper crush washer and it just has a rubber diaphragm inside it with a spring. You may substitute the rubber diaphragm with a neoprene washer from a hardware store and reuse the spring. I personally didn't take mine apart, I just cleaned it with PB spray and an air hose.

That's actually really interesting, maybe your contacts needed to be sanded? I just bled my system Saturday night and used a pressure switch from NAPA no problem. I had been using a push button style switch that I also had clamped to my steering column back when I went to a dual MC but recently just swapped it back out for the original due to performance issues. I also replaced the switch contact with one from NAPA since mine was pretty corroded. To be fair the system only worked for five minutes before the first and second seal broke in the MC and fluid began dripping from the bypass hole... guess I should know better with it sitting dry on the shelf for the last couple years...

Surgical tubing and Coca-Cola bottles work pretty good. Plus you have to drink the coke, so you get a nice refreshment.

The master cylinder does not need to be bench bled because the fill reservoir introduces fluid to the master cylinder at its highest point so air bubbles cannot be trapped. You need to keep filling until the bubbles stop, then bleed the brakes like normal. The stop light switch will not work if air is in the system. If it doesn't work after bleeding, then it needs to be replaced. Because it is part of the hydraulic system, if it does need to be replaced then the system needs to be bled again. I personally would not reuse the old switch. Napa sells the pressure switch and is readily available.

Although I have nothing to offer you, I will say that even with stock hand cranks, I have this issue and have to pull them away from the door for the knobs to clear the stainless. You may have to remove them again and shim them out.

While I don't doubt the abilities of GM power steering fluid, and it's most likely not an issue with modern seals, but it was suggested to me that I use the same type of fluid that was originally used - ATF fluid, simply because the pump and box were engineered for that specific fluid. You are right that fluids have significantly changed since 1956, but modern power steering pumps and assemblies are engineered for PS fluid. From what I was told, it just never occured to me to use PS fluid.

The only difference between Dot3 and Dot4 brake fluid is boiling point, but Dot4 will only be helpful to you if you do a full bleed, otherwise it adopts the characteristics of Dot3. Personally I use Dot4 because the brake line goes underneath the low part of the oil pan and the friction action of the brakes already build up heat to begin with, so raising the boiling point puts ease of mind. As others have said, I've only ever used ATF fluid in the PS units. You will need to flush your PS system before filling and bleeding, however, because I think the fluid is to keep the reservoir primed. I got both units rebuilt by Lares Corp and had to flush both units until it was the ATF red coming out at a constant rate. Your master cylinder looks great by the way. I rebuilt mine and painted it like that a few years ago, doesn't look as shiny anymore.

After doing a quick search, it looks like they used Rochester and Carters just like Buick. When I was looking, I only noticed the silencer on 55 to 57 models. I haven't seen the silencer on any other GM car.

Didn't Pontiac use the silencer air cleaner?

Don't get me wrong, CARS is my favorite distributor with Bob's and Kanter behind it, and I always go to them for the hard to find stuff. It's just when I find stuff still being made today and their prices aren't even competetive, especially with the $20 shipping they tack on to every order, I get a bit frustrated.

You know it just really bothers me that these restoration websites will bend you over for a quick buck. Classic Buicks, CARS, Fusick all want upwards of $20 for a spring kit and don't even get me started on the self adjusters. It's a good thing Fusick messed up and posted and picture of their kit, because I wouldn't have been able to match up a NAPA kit with the exact same colors. There's also two other kits offered through NAPA that are similar, and for their prices I'll just order all three and compare springs in store before buying. If they aren't the same, I'll rescind my statements, but come on... Fusick kit NAPA kit NAPA other 1 NAPA other 2 (looks like the Fusick Roadmaster kit) And here's the adjusting screw - $6.75, NOT $21.50... I just can't believe it. If you want them individually: Adjustment spring Hold down spring Hold down cup Hold down pin Return spring The only thing I can't find are the rubber plugs. Some of these were also sourced from a 1962 Electra, but the adjuster spring was the same to 1958 and 1952-1960 apparently share springs. Brake shoes and drum sizes are all the same. Wheel cylinders are the same from 1956 to 1962, and all the springs are the same for front and rears so I don't see why they would change springs? Anyways take all this with a grain of salt. It's extremely frustrating to me that people operate businesses like this. I guess they did their research and bank on others not doing their own.

NAPA stocks them regularly on their miscellaneous racks. I bought a few this year, along with a new light socket assembly for my trunk light. They're on the same rack with the various switches (On-Off, 3-way, starter, horn, etc.).

The pressure is exerted by the piston. It's not the original mc causing too little pressure, it's the newer large bore mc that are not putting out the required pressure. To my knowledge you cannot sleeve these without having access to smaller pistons because they actuate within a bore similar to a car engine piston. The original mc piston is pushed into a fluid reservoir and displaces fluid that way, there is no bore that it rides in. The only manufacturer that makes the correct piston is Wilwood but it's a manual clutch master cylinder.

I was actually a little bit curious because I have the Scarebird disc brake conversion that uses roller bearings from a 1977 Riviera. Turns out it's the same bearings all the way back to 1963. I am more than positive this will work! As soon as I get a hold of the seller, I will do an update to the thread. Found the parts list for the Riviera rotor in the kit: 1946-56: BR51 1957: BR5 (1963-77 Riviera) The BR51 has the same dimensions as the BR5 wheel bearing, except the ID is 1.5" on the BR51 and 1.375" on the BR5. These bearings are confirmed to work on my stock spindles with the disc brake conversion.

Thanks for the post! These drums are not 2 1/2", rather 2 1/4" so I can use my original backing plates if I do get them. Would like to find some 2 1/2" but beggars can't be choosers