69 c50 brake questions

[BHM298]

Just bought a 1969 c50 for 850 bucks. I drove it to a place I can store it for the time being. The PO said the master cylinder was shot, but I found a busted brake line that needs to be adressed as well. My plan is to upgrade to a dual circuit MC, firewall mounted booster and new lines front to rear. Any suggestion on what parts to use for the MC/booster combo?

[BHM298]

Sorry for the sideways pic

[mrolds88]

My first thought would really be to look over the stock system. The hydravac system is a good one. Parts are available.

[jumpsoffrock]

Not sure how similar your system is to mine in my '67 C50, but I had to do a bit of research to find all the parts, and then I had to do a TON of research to find 'em for the best price. I finished the brakes about two months ago after many many weeks of work, waiting, work, and reassembly.

Here's where I started:
http://www.raybestosbrakes.com/magno...=Medium%20Duty


A word from the wise: expect NOTHING to be in useable condition. Thoroughly inspect EVERYTHING before calling off further work on the brake system.



...those damn rear drums are heavy sombiches

[BHM298]

Originally Posted by mrolds88

My first thought would really be to look over the stock system. The hydravac system is a good one. Parts are available.

My biggest concern was it bein a single circuit and losing my brakes with a load on it.

Jumps , did you go with the stock setup too?

[jumpsoffrock]

To be honest, yes I did. I know it's taboo to say, "it's too much trouble to modernize to a dual circuit and possibly save my life"...but that old single circuit system worked for many extremely hard days without fail.

I really am putting a lot of faith in it's ability to keep me alive and well, but I just don't know enough about changing brake systems to make a seamless and quick changeover(...that won't leave my truck off the road for months and months while figuring it out).



The only things that were not replaced were the rear brake shoes, a few random springs that weren't in the spring kit I bought, the main section of brake line from the front to rear of truck, and brass splitters. All lines were inspected and did not have bad rusting on outside, and all old lines removed were inspected for pitting on the inside as well as I could, and no pitting was found so I assumed the rest of the old lines that I left in place were good.
EVERYTHING else is brand new. Everything. (master was remanufactured)

[BHM298]

Thanks for the insight. If you don't mind me asking, what do you use your truck for?

Did you get all/most of your parts from raybestos? Is anything going to be able to be sourced locally at parts stores etc?

[jumpsoffrock]

I am intending on using the truck as somewhat of a car hauler and just a general work horse between my extended family and I(anyone who needs it).


Oh man, this is such a long-winded and tough explanation!

Here's the thing, I used Raybestos website as a starting point. As an example we'll discuss wheel cylinders because that's what I did the most homework on when finding parts. Many different manufacturers make the identical wheel cylinders for our truck. Raybestos website can find me their part number, and from there I would scour the internet, using everything from ebay to a place called http://www.yoyopart.com/
only to cross reference part numbers.

So I would start with Raybestos' part number, and end up with alternative part numbers for the same exact part from let's say, BENDIX, WAGNER, and NAPA brand.

Once I had these part numbers, I would go onto a website called https://www.rockauto.com/, and use their parts-number search engine to track these parts down.


I found that I could save between $5-$30 on EACH part just buy finding other manufacturers that had parts on closeout, or were just plain cheaper. All of my wheel cylinders--all 6 of them--were on closeout, and got them for reasonable prices.

Another example was my front brake shoes. Raybestos' brake shoes found on Rockauto were over $100, but I found part numbers for the same exact riveted shoes from WAGNER on closeout for $65.



That's how I found every part for my brakes except the Master(ebay), some parts were better deals than others--All flex hoses were bought at retail price...couldn't find a deal. But my spring kits--front and back--both only cost me $5 combined(closeout comes to the rescue!)!


Sorry for my rambling. This was a stressful project, but I did save myself probably about $200 by the end of the day compared to if I just bought the first thing I saw, and probably saved even more compared to making a one-stop-shot at NAPA.
NAPA easy? Yes. Cheap? No.

[BHM298]

Awesome information! Brakes will be my first project and of course, the most important part of the truck. I plan to tear into this truck within the next month. I'll have to start scouring the web

[jumpsoffrock]

Oh, one last piece of valuable info:

I made a mistake and searched for weeks to find the best deals on rear wheel cylinders....only to find out they were for the base 15"x4" rear brakes. At the time I didn't actually know how to remove the drums, and they were too heavy for me to just "experiment" with. so I assumed their size.

After going through hell to get the parts, I come to find I have the optional 15"x5" brakes........all of those darn cylinders? WRONG PARTS


If you can, tear apart brakes first.

[mrolds88]

And as part of your looking for good prices, if you have a wagner or raybestos number, plug them into Rockauto. They may just surprise you.

[BHM298]

Alright cool. Do I just need to measure the drum diameter to tell the difference?

[jumpsoffrock]

In my experience that didn't work out so well. Remove rear drum/hub and measure shoes. You're going to need to do this anyways.

[colgad]

I have done this job two ways. First i rebuilt the system using replacement parts but converting to a split system.
Excuse me but having a single system is just NOT the way to go. I have been in a Truck that lost a cylinder and then having no brakes at all is not fun coming up to a busy intersection. If your restoring a museum piece then yes keep a single system but if your going to use your truck and keep it, why put your life and others at risk. Its a simple conversion to a split brake system.
Once done you still have drum brakes and widow maker rims.

The second C50 I did I went with all disk brakes. I know not cheap but SO SO SO much better and the parts are available everywhere. The easy part is to just swap out your rear end. This is pretty easy and really not that expensive. You get modern 10 lug 22.5" rims so you can run modern tires, gone are the 20" widow makers. The front is harder but do able. Find a GM P30 bread truck that has a straight axle and you can use the spindles with a small mod. This will give you disk brakes and 8 lugs than you can use adapters to go to 22.5. 4 wheel disk brakes on your C50! I used 2001 Chevy 3500 booster and a 1992 Topkick master cylinder. Small firewall mod but worked great.

I swapped my front axle for a freightliners it was too wide so I cut 10"s out of the center and welded it back together. Not for everyone but worked for me.

[BHM298]

Colgad, when you ran the 3500 booster and top kick MC was that on your drum setup? What prop valve did you use? Thanks for the disc conversion info as well. Doubt I'll do that anytime soon due to how often (or lack of) it will be used, but definitely good info.

[colgad]

Originally Posted by BHM298

Colgad, when you ran the 3500 booster and top kick MC was that on your drum setup? What prop valve did you use? Thanks for the disc conversion info as well. Doubt I'll do that anytime soon due to how often (or lack of) it will be used, but definitely good info.

I use an adjustable one from ebay $32. That way I control when the rear locks up :-)

[BHM298]

Alright I'll probably do the same. What did you have to do to modify your firewall?

[colgad]

The 4 bolts that held the old booster on are wider than the new booster. So I had to drill new holes. You will need to make an extension to the new boosters rod that connects to the brake petal. I used the old booster parts to do it. It took me maybe an hour.

[MjrBummer]

Awesome info Colgad, thank you for your input. I've been wanting to upgrade the brakes on my 67 C50 Skewlie. This info will come in real nicely.

Bill

[MjrBummer]

Also, when you say, "Find a GM P30 bread truck that has a straight axle and you can use the spindles with a small mod", what kind of mods did you have to do?

[colgad]

Originally Posted by MjrBummer

Also, when you say, "Find a GM P30 bread truck that has a straight axle and you can use the spindles with a small mod", what kind of mods did you have to do?

Here is an paragraph from the Stovebolt fourm
The thickness of the I-beam axle end where it fits into the spindle is the same for both P-30 and 2 ton AD axles, About 3.050".
The angle that the kingpin leans in, known as kingpin inclination angle, best I can measure is the same for both axles.
Kingpin length is essentially the same, and the lock pin groove is in the same place.

Now it would be to easy if everything was the same... here is the major difference:
The kingpin diameter on the 2 ton axles is 1.109", and on the P-30 it is 1.179".

Two methods of adapting the P-30 spindles to the old axle:
Use thicker walled bushings, but I've been unable to find any ready made ones. You can order oversize bronze ones and turn and bore them to suit, probably have to mill the grease groves too.
Or you can make thin sleeves to press in the kingpin bores in the spindles to adapt them to the original size smaller OD bushings. So far I like this idea best. I'd use green loctite sleeve retaining compound so they stay put, and in the future new kingpins and bushings are an off the shelf item.

The 1.109" kingpin kit you would use is NAPA # 262-1016. There are other similar kits but this is the best choice from what I can see because it comes with gaskets for the caps on the P-30 spindles, not steel plugs like the old 2 ton had, it has bronze bushings not plastic, and has a ball thrust bearing not a thrust washer. It's also cheaper and easier to get than the other possibly suitable kits.

http://www.stovebolt.com/ubbthreads/...&Number=725027