Hi forum members,
I have an old 1970 Bluebird bus built on a C40 Chevy Chassis. It is a short bus, not one of the long ones. It was converted into an RV when I got her 15 years ago. About two years ago I had its two vacuum canisters replaced (vacuum assisted brakes) because they were leaky and could not be relied on. Because I rarely use the bus over the years as our kids are grown and out of the house, etc., I found that when I got her ready to travel, the vacuum assisted brakes are acting up. The brakes will not slow down when pressed.
I have to press hard on the pedal and then the bus stops, it does so quickly almost on the dime. Contrast this to how it stopped before where the slightest pressing of the brakes started the braking process so that I could slow down if I chose to or slam on the brakes if needed. It is behaving as if there were some type of stuck mechanism that lacks lubrication, maybe a stuck valve or something. A friend suggested that there should be some type of check valve going into the vacuum canisters and that I should see if it is stuck by taking it apart and seeing what I find.
I was wondering if I could simply disconnect a fitting somewhere in the vacuum system and then spray wd40 into the vacuum lines and see if I can work out whatever might be stuck.
Anyone have any thoughts on this and what might be going on?
Thanks for any help.
Tony
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I have an old 1970 Bluebird bus built on a C40 Chevy Chassis. It is a short bus, not one of the long ones. It was converted into an RV when I got her 15 years ago. About two years ago I had its two vacuum canisters replaced (vacuum assisted brakes) because they were leaky and could not be relied on. Because I rarely use the bus over the years as our kids are grown and out of the house, etc., I found that when I got her ready to travel, the vacuum assisted brakes are acting up. The brakes will not slow down when pressed.
I have to press hard on the pedal and then the bus stops, it does so quickly almost on the dime. Contrast this to how it stopped before where the slightest pressing of the brakes started the braking process so that I could slow down if I chose to or slam on the brakes if needed. It is behaving as if there were some type of stuck mechanism that lacks lubrication, maybe a stuck valve or something. A friend suggested that there should be some type of check valve going into the vacuum canisters and that I should see if it is stuck by taking it apart and seeing what I find.
I was wondering if I could simply disconnect a fitting somewhere in the vacuum system and then spray wd40 into the vacuum lines and see if I can work out whatever might be stuck.
Anyone have any thoughts on this and what might be going on?
Thanks for any help.
Tony
