Complete Brake Job

[Red Horse]

Ok Guys, any thoughts?. About to sand blast my B chassis. FA-522 front axle and RAD 111 rear. 24" My question is, given the fact this thing is a 1960, what parts would you think would likely require replacememt- other then the obvious of linings, hoses diaphrams. I have a new set of Maxi's for the rear. I'm asssuming things like slack adjusters, shoes, bushings etc should stillbe available?

Anythoughts would be appreciated. I'm not doing this yself so I have tothink about trade off of labor vs new etc.

[Firemack]

Redhorse,

I just updated a 1960 B 95 Firetruck, put in all new hoses, diaphrams, (type 30-30) added the spring-parking brake, The slack adjusters were OK, so I left them alone- but they were stock parts and available. The only parts you may have trouble getting is the actual shoes, on this truck were OK, but I had our 1954 B 75 Mack shoes relined by National Transaxle, so there should be someone local that can do that for you.

Firemack

[vanscottbuilders]

Depending on your intended usage - the level that you take a brake job to may vary.

I probably go a little overboard - just because.

Getting the cast aluminum shoes relined is a little challenge.

Seems that fitting and bolting on new block type linings is almost a lost art.

With some patience, and some good coaching, and some more patience,

and a little beer, I now do my own. That came after three tries by a local shop.

The linings crack very easily!!! Practice first. Check the fit very carefully. The cracks are

hard to spot but they will definitely shorten the life of the brake job. Pitted or delaminated

shoes need to be replaced. (Contact Kevin All at AllMacks for original replacements)

All of the shoe bushings should be changed and the wear pads turned around or replaced.

The S-cam bushings should be checked and changed as required. Loosen all of the

eccentric adjustment bolts and apply Never-Seize before reassembling the eccentrics.

There are some felt dust seals in the rear brakes that should be changed.

The return springs need a good close examination, and replace as necessary.

The "nails and springs" that hold the shoe centered should be examined and the C-clips changed.

Be sure the retaining washers are adequate. They are a fender type washer. A regular 1/4" washer

will slip thru the shoe, and the shoe will chatter. Bad wear and poor braking are the result. Almost every

one I've had apart had this problem.

I like turning the drums for a good surface, but I think most are probably OK as is. Again, it's up to you.

New drums are always a good choice for heavier or more regular use.

Fitting the new shoes and linings to the drums is a bit of an art. Just read the service manual and follow directions.

From a detail stand point, I like to clean and paint all the parts before reassembly. I have found

that any of the common "rust-converter" coatings work pretty well for this purpose.

Use minimum grease on the contact points of the S-cams. Grease attracts dirt. Dirt leads to wear.

Try a dry lube or a motorcyle/bicycle chain lube that will not pick up dirt.

Clean, check and repack the wheel bearings as long as you are in there. New seals might be in order too.

I have found some difficulty in getting all of the parts from Mack, unless I was willing to buy whole bags of the obsolete stuff.

You might contact Matt Pfahl for these parts. I think he has a good selection, and he treats people very fairly.

On the old trucks, I like to change the brake cans, and, as you are doing, convert to Maxi brakes. I change the slack adjusters, too,

if they are the old original type. It might start a war here - but I do not care for auto-slack adjusters, so we use all manual type adjusters.

If you are not changing air lines from the old copper, be sure to check all the air plumbing over very carefully. I like to convert to all

plastic lines and new fittings for regular use. The brass thru-frame bulkhead fittings at the front axle are particularly fragile, and should

be examined for corrosion or any sign of failure.

These brake systems are pretty straight forward.

When you get the units apart - it will make a lot more sense.

Good Luck,

Paul Van Scott