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Author Topic: Leveling valve leveling system and leveling valve question  (Read 1961 times)

Offline Lin

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Leveling valve leveling system and leveling valve question
« on: October 23, 2012, 03:04:52 PM »
I am beginning to install a leveling system similar to what Bob G. has described using cables and the existing leveling valves.  I went to install it on the front first to see if it would work as I have planned.  I tried to test how much range up/down it would give me, so I pushed the valve lever all the way up, measured, and then pulled it all the way down.  When the valve lever is pulled down, the exhaust hisses and some air comes out, but the bus does not lower at all.  It actually seemed to go up another 1/4" or so.  It therefore seems the the leveling valve is bad.  It always worked to raised the bus and would leak down in about a day, but I never did have cause to see if it lowered the bus.  Anyway, am I right is assuming that I should just replace it and not mess with trying to clean it out?  It appears that my front valve has the same orientation as the right rear.  Is it the same part or are fronts somehow different?
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Offline robertglines1

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Re: Leveling valve leveling system and leveling valve question
« Reply #1 on: October 23, 2012, 03:46:30 PM »
I just replaced mine and all three were the same.  Bob
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Offline Lin

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Re: Leveling valve leveling system and leveling valve question
« Reply #2 on: October 23, 2012, 03:55:11 PM »
My rear ones might be the same if the lever is reversible.  The front, which has the lever extended like my rear right is not reversible.  Must be much older.
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Offline Don4107

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Re: Leveling valve leveling system and leveling valve question
« Reply #3 on: October 23, 2012, 08:59:37 PM »
The leveling valves have built in delays so that they don't try to level on every little bump.  It takes some time for them to react.  How long did you wait?

Our new to us 5B has a very simple leveling system.  You open the little door that was the rest room service access and now there are two valves, left and right.  They are plumbed between the leveling valves and the air bags.  There is no adjustable leveling for the front axle.  I may add a similar system to lower it for easier access to the first step.

There are three positions.  1. Normal  2. Lower 3. Hold.
Normal lets the leveling valves work normally.  Lower exhausts air and lowers that side.  Hold blocks the line so leveling valves can't work. They hold air for a long time this way.

Even with these valves exhausting what sounds like a lot of air, it take a fair amount of time to lower that side.
Don 4107 Eastern Washington
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Offline Lin

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Re: Leveling valve leveling system and leveling valve question
« Reply #4 on: October 23, 2012, 10:25:07 PM »
I know about the delay, but this one does not exhaust at all.  I left it for an hour before I loosened the air bag supply line to let it drain.  I still wanted to see how much range there would be between full inflation and when it hit the stops.  There is only about 5 inches, which is not too much.  Considering it would normally be in a middle position, this would mean the front would only drop 2-3 inches.  Assuming the back would be the same and I could raise it 3" above normal, it would be a total of close to six inches of adjustment.  That would cover most situations, but I would still carry blocks.
You don't have to believe everything you think.