11-08-2019, 12:12 PM
Deja vu. After I bought the '87 I had leveling problems and they were caused by a few factors. My problem may have been different than yours but maybe this will help. I found the best way to deal with it is to make a diagram of your leveling system, label everything related to the valves and then in this order start diagnosing:
1. Make sure every single wire coming from the manual leveling switches in the front of the coach (mine are in the mid console) go to the valve they are supposed to go to. Mine were not. Also make a terminal in the back for the valve wires as it is much easier to work with/diagnose.
2. Make sure the main switch to go from auto level to manual level is the appropriate switch. Mine was an off/on switch and it needs to be an either/or switch. The auto level is normally on when the ignition is on unless you switch that switch to manual level.
3. If there is still a problem it may be the leveling valves. (It was with mine. After fixing the other 2 problems we replaced both rear leveling valves and I have not had a leveling/air leak problem since.) I was told these leveling valves get crud in them and there is a screen that gets plugged up and/or they just wear out.
These are some notes I made to myself (I knew nothing about this system at the time) and maybe they will help:
.The auto level airline from the auto valves goes to the front leveler valve and when auto wire is activated I think the front and the back auto leveler valves open. Air goes out of the bags/tanks through the auto valves and out the hose to the front leveler and air is expelled from the leveler valve itself. When the bus is down to where it should be the leveler valve shuts off and the air stops being expelled. If the bus goes down below level, the leveling valve allows air back into the 6 pack (through the same air hose that the air comes out of the 6 pack to lower it) to raise the bus back up.
. One airline comes from the brake air tank and that is the supply air. There is a pressure valve on the line from the brake air tank that turns off the flow if the brake air gets low. The other air line at the leveler valve goes to the solenoid. So when the auto solenoid for the L side is open, the manual L side solenoids are closed and the valve allows the air in from the brake tank to the auto solenoid to the air tank/bags L side to raise the L side until the driving level is reached then supply air is shut off. If the L side is too high the L level valve will keep the supply shut off and allow air out of the bags through the open auto solenoid to the valve exhaust to lower the L side until driving level is reached.
I'm not sure how accurate the above statements are but that is what I understood at the time.
The photo shows my rear valves and my diagram of my air system which may not be exactly correct but it is to the best of my (small amount of) knowledge.
Hope I helped.
1. Make sure every single wire coming from the manual leveling switches in the front of the coach (mine are in the mid console) go to the valve they are supposed to go to. Mine were not. Also make a terminal in the back for the valve wires as it is much easier to work with/diagnose.
2. Make sure the main switch to go from auto level to manual level is the appropriate switch. Mine was an off/on switch and it needs to be an either/or switch. The auto level is normally on when the ignition is on unless you switch that switch to manual level.
3. If there is still a problem it may be the leveling valves. (It was with mine. After fixing the other 2 problems we replaced both rear leveling valves and I have not had a leveling/air leak problem since.) I was told these leveling valves get crud in them and there is a screen that gets plugged up and/or they just wear out.
These are some notes I made to myself (I knew nothing about this system at the time) and maybe they will help:
.The auto level airline from the auto valves goes to the front leveler valve and when auto wire is activated I think the front and the back auto leveler valves open. Air goes out of the bags/tanks through the auto valves and out the hose to the front leveler and air is expelled from the leveler valve itself. When the bus is down to where it should be the leveler valve shuts off and the air stops being expelled. If the bus goes down below level, the leveling valve allows air back into the 6 pack (through the same air hose that the air comes out of the 6 pack to lower it) to raise the bus back up.
. One airline comes from the brake air tank and that is the supply air. There is a pressure valve on the line from the brake air tank that turns off the flow if the brake air gets low. The other air line at the leveler valve goes to the solenoid. So when the auto solenoid for the L side is open, the manual L side solenoids are closed and the valve allows the air in from the brake tank to the auto solenoid to the air tank/bags L side to raise the L side until the driving level is reached then supply air is shut off. If the L side is too high the L level valve will keep the supply shut off and allow air out of the bags through the open auto solenoid to the valve exhaust to lower the L side until driving level is reached.
I'm not sure how accurate the above statements are but that is what I understood at the time.
The photo shows my rear valves and my diagram of my air system which may not be exactly correct but it is to the best of my (small amount of) knowledge.
Hope I helped.