2nd newbie question, what's the deal with brakes?

I'd say Bendix are as good as any. What is 3030?

 

@NorthernMechanic ??? Heck I drive Pete's and occasional Macks, and I have no clue... would like to know, as well~ thanks guys.

 

It's says size 3030.
But what unit of measurement are they using is the next question

 

3030 is the brake chamber size. 30 square inch diaphragm in the parking brake chamber and 30 square inch diaphragm in the service brake side. You can have like 2430 or whatever else. 3030 is the most common on heavy trucks though.

The chambers don't usually need to be changed unless they leak or the park springs are broken. You check for broken springs by remove the rubber plug on the back, if the slot inside for the caging bolt is not centered and way off to one side, the spring is broken. Or if you give the chamber a light tap with a rubber hammer and it clunks, spring is most likely broken. If they're heavily corroded, change them. Also don't throw them away in scrap metal pile or garbage. They need to be taken to a shop and disarmed. Basically they'll lock them in a heavy steel box with a slot in the side and cut the spring with a torch.

 

^^^^^^ Thank you SO much, NM. Again, you save the day. This had ME baffled as well; I'm ASA certified but not diesel, yet I do much of the work on the boss man's trucks. This was extremely informational; and when I head in to drive tonight, I'm gonna check this out. Yeah, we have our regular brake man, but I just feel like a HEEL when I don't know this stuff! Thanks for the rescue man, you are worth your weight in gold.

ps: I've done many a brake job on the Pete's but the Macks are just a bit different; feel like it's out of my league. Where do you actually FIND these spec's?

 

all trucks are same with brake chambers or boosters the number means the size of the chambers and don't worry about disarming them just chuck them in the scrap metal

 

Not a good idea. Not only is it stupid but If the wrong people were to find out about it, you better hope you have a big bottle of KY ready. Even if the spring is broken, it could still be under tension. If something were to happen at the scrap yard and the chamber broke open, someone can get hurt. What if someone was curious as to what was inside the chamber and decided to cut it open?

 

Bumping an old thread... But I remembered seeing this, so I thought I'd add to it a bit. As it was already mentioned, chambers can be very dangerous, and depending on its condition, it can be a ticking time bomb just waiting to unleash on you/someone.

I usually wait until I have a dozen or more in the bin before I go through them, but, here's what I do with them, and have been doing this for years. Kind of a step by step... just cause I have something outside that needs to get done, and I'm procrastinating. And, since I thought of this thread, I snapped a couple of pictures.

First, although it may seem like a pointless pic of any ole chamber, the point of it is, is that when I'm getting them ready to scrap, I'm facing the side of them... Not straight on from the end.


Next, with an oxy/acet torch, I burn a hole in the center of the spring cover. The whole is approximately 1" diameter. Its just big enough to reach in with the torch tip, and cut the spring in half. This is the part that its important to be facing the side, and not the end. When you make that first cut, the majority of the tension releases, and it "snaps" fairly hard. I have had a chamber that had a VERY rusted cover, and that snap was enough to knock the cover off, and send it several feet.


After the first cut is made with the spring, I cut a slot, so more of the coils can be cut.


And then finally, I cut a large chunk out of the side of the cover, to make it very easy for people to see that the spring isn't a problem.


It takes me about 2 minutes to cut one up... just shy of a half hour for a dozen. When the excavator operator at the scrap yard is careful about bumping them when there are people around, it kind of shouts out how dangerous they consider them. When they are cut apart this way, they know, from a distance, that nobody's gonna get hurt!

The scrap yard is happy to see this done, and when they are happy, they pay more! Extra money on the chambers doesn't mean much... But, when you bring a bunch of chambers on the first load, and then right behind it, bring an extra 30 or 40 tons while they're still smiling... Well... Then EVERYONE is happy!