Hey everyone im new to the skoolie life. I recently purchased a 3800 t444e short bus.

[leftoutinc]

This bus runs good does need some preventive maintenance that was neglected. My question is that my skoolie have the brakes with calipers and a flip down emergency brake And it seems as if the master cylinder has a motor built into it on bottom. As soon as I turn key on it is humming very loud and never stops unless un plugged. Also it's like my back drive brake is dragging enough that a 15 mile trip it heated up enough to start smoking and smells like I locked the brakes up. No visible sign of leaks. Any advice is appreciated.

 

[nikitis]

Should take pictures of your brakes so we can see what you got.

 

[sportyrick]

WOW you need brake work BAD, they dumped a problem in your lap and it's not a cheap one to remedy, bet you got it cheap!

 

[magnakansas]

That motor running is a back up pressure motor. You have a bendix hydroboost system. There is a problem if the electric motor is running after the engine is started. This system uses the power steering pump for brake assist. Go read and learn how this system works. I suggest 10 hours study time minimum. YouTube university should help if you are a visual learner.

William

 

[Carrier6]

That motor running is a back up pressure motor. You have a bendix hydroboost system. There is a problem if the electric motor is running after the engine is started. This system uses the power steering pump for brake assist. Go read and learn how this system works. I suggest 10 hours study time minimum. YouTube university should help if you are a visual learner.

William

The motor that is running is the battery back up to the brake booster. It uses battery voltage to run the booster because the power steering pump doesn't build pressure when the engine dies. This is used for emergency stops.

 

[Carrier6]

Did you unplug the wire on the master cylinder to get the motor to stop humming before you drove it? Or did it smoke the brakes while it was plugged in?

 

[magnakansas]

No you don’t unplug the motor. You figure out what is wrong and repair the system. The motor is running because there is a problem.

William

 

[Carrier6]

No you don’t unplug the motor. You figure out what is wrong and repair the system. The motor is running because there is a problem.

William

Yes, that's what we are trying to determine what he did.

 

[magnakansas]

Have you found the bendix online manual about this braking system? Have you repaired the system?

William

 

[heimlich]

I have that same bus. I'm here in Houston.

Mine has hydraulic brakes. There is a safety feature in these busses for when the hydraulic pressure goes out. If you don't start the bus and turn the key on you can hear it when you press the brakes. This is a hydraulic booster. When you run the bus I don't think it works. it's only for when the brake pressure from the engine disappears.