No brakes! Bugger!

[dentedvw]

Long story short, I am supposed to drive this bus from Michigan to Salt Lake City, Utah beginning June 2nd. It's pretty flat most of the way, but I will need the brakes more and more as I pass through Colorado.

This wee little plastic switch broke off the side of my master cylinder.

I THINK that's why the brakes stopped working. Pedal hard as a rock. The threaded section remained in the MC, and I can't get it out. The brake lines are pretty well permanently rusted to the whole darn thing. They will need to be cut. I could splice it back together with more hardline later, if need be, using a flaring tool, bender, and fittings. I have done it once, on my Jeep. Seems like I could do it again.
Here is the ugly beast though.

Yeah, everything looks like that. Rust is holding the rust together. On a good note, the floor is pretty solid. Somehow.

Just the booster is around $200 on eBay. I don't know what to look for regarding the master cylinder. There is no tag, or anything to tell me what the chassis of this bus is, so that doesn't help.

The way I see it, I have two options:

• 1.Pull the entire brake booster/master cylinder and replace. I would need to replace some of the hard line as well, because it would require cutting them. could I get some flexible line to make up the difference? Is it worth it? I could simply get some short hard lines and bend them up, around, and put them back onto the original hard lines where I can, using a flaring tool, bending tool, etc. I could probably get a used brake system at a big truck salvage place in Grand Rapids. Otherwise, I would buy new. I don't know what that would cost.
  2.Take it somewhere, make it a headache for somebody else. I don't have enough money for this, not even close. I would end up putting it on a credit card, which I am loathe to do. I may need that cushion for fuel. And food.

Help me decide. If I go with option one, I will not be able to move the bus if I fail. If I go with two, I can drive it to the shop, using the hand brake. That still works.

[frank-id]

My suggestions are..... you must begin to educate yourself about this type brake system. Approach this challenge as seriously as you can. By learning all ya can, you will save time, parts and money. First take many pics of the area and the seperate pieces. Print the pics out to show others. If this bus is a local bus, go to the school district or previous owner. Big truck brake shops should know about your project. Call everyone who might assist you. You may need to pay for some information in beer or cash.
Post a picture of this vehicle, as front, rear, dash, inside brake pedal, and lots of pics of the unit. The plastic part does not show well thru the package. My guess is the part is either a brake lite or low fluid switch. Check to notice if this unit is connected to the power steering pump. GM created a brake system using the power steering pump pressure. My clue was the word hydro max brake booster. Or this can be a vacuum brake system. I guess for sure the system is hydraulic not air brakes. You have a really rusty task. Go buy a few cans of PB Blaster and allow to loosen all the fasteners. Magic rust buster....Frank

[dentedvw]

PB blaster hasn't made a dent in much on this bus, sadly.
But, some news. You are on the right track mentioning the power steering pump. I think that is involved. I found that steering was terribly difficult sometimes, and at those times, I could hear the electric motor kick in and it would get better. So, having said that, I went in search of the power steering pump. Might as well be at the end of the rainbow. I can't see anything on the front of this engine.
So, I look for the reservoir instead. BINGO. EMPTY. Well, might as well be, the dipstick had the tiniest drop on the bottom. And it was hard as heck to pop off too.
Since the res doesn't say whether I use power steering fluid or not, now I am stumped. I googled the part number on the reservoir bottle, but no love there.

Does anyone else have this chassis? I remember a few others, but I don't' know anyone personally.
If I could find out PS fluid, or brake fluid, I would be ten paces ahead of yesterday.

[Jarlaxle]

Not the same chassis as mine, but...I suspect what broke might be the sensor that TELLS the auxiliary booster pump you need power brakes! If so...you need to fix that!

Removing rusted brake lines: three times a day, heat them GENTLY AND CAREFULLY with a propane torch. Quench them with penetrating oil. DO have a fire extinguisher handy when you do this! I have gotten lines that spent 25 years on Cape Cod (never more than 2 miles from the ocean) off this way.

Make sure the power steering is topped off...this is hydroboost (the "HYDRO-MAX" booster pretty much guarantees that one!) and won't work without PS pressure.

[Jive Turkey]

Anyone interested in doing a Hydro Boost clinic? I can help educate anyone interested in learning the inner workings of the Hydro Boost and system. Anyone interested PM me your email and I will send you a pdf and any questions you have I can answer.

I highly recommend this book for anyone interested in doing their own repairs. While it isn't a repair manual it is a great teaching aid that will explain almost if not all the systems that are on your bus. You can pick up older copyright dated and/or used copies for much cheaper than what the newest book is going for. Why bother buying the 2010 book if your bus is a 1998 you can get the 2001 copy.

[Seeria]

Oooh might have to grab that one. Thanks

[Stuff]

Originally Posted by Jarlaxle

Not the same chassis as mine, but...I suspect what broke might be the sensor that TELLS the auxiliary booster pump you need power brakes! If so...you need to fix that!

im assuming the same thing

[Jive Turkey]

That's exactly what it does it's called a flow switch.