Brake Tank Pressure Vulnerability
There r a few we have discussed here before I'd like to add another.
Twice now I've traced down a pressure loss that showed up at the dash gauges. The complete loss of air when parked in a day or 2.
This was a reletivly easy one.
For sure from 2000 on and quite possibly to include earlier chassis.
Under the floor under the driver on the ceiling of that compartment u see the bottom of the brake pedal valve.
There r many green and red plastic hoses of various sizes coming out of all 4 sides.
Out the back there r 2 45 degree fittings. 3/8 pipe to 3/8 plastic and a red and green 3/8 plastic lines going into push in fittings.
I have thought I had aquired a pretty good sence of being able to determine by the size (sound , bubbling or rate) of the leak weather or not it is all the loss or there is more.
I was only kidding myself when I found this once again yesterday.
The first chassis I encountered with these specific fittings leaking I could hear it as soon as I opened the door. That's happy days for the bus cause probably it's the Lions share if not all of the air loss.
Yesterday no audible leak and if I didn't spray solution in the right amount in the right spot u may or may not make bubbles. I verifyed the leak with a ultrasonic leak detector first and only then was able to correctly direct the spray in a spot to make bubbles.
Its not easy to get at the door only opens half way and u have to be very Carful spraying around all the electrical components.
What seemed like a slight leak yesterday turned out to be the entire problem. I thought for sure it was about half the loss but it cured it.
If u have pressure loss when parked at the brake tank gauges look here as I described. Replace those 2 push in fittings with compression.
