Front Suspension Dump

[TOPHAT1]

This past week I wanted to level the coach and started with dumping the suspension. Well, the rear of the coach drops but the front stays up. So from this scenario, my assumption is that there are two dump valves. One for the front and one for the back. If so should I have two Clippard valves a Clippard valve for each Dump valve? I only see one Clippard in the area under the drivers window, am I looking at the correct location?
If I have two Clippards, which air line do I remove to find out if the Dump valve is functioning. And is there any diagnostics that I can perform other then resistance and voltage checking of the Clippard and what is the resistance suppose to be?
Next if the Dump valve is the problem where is it located and does anyone have a pic of what it looks like? Does anyone have the part number for the Clippard and Dump valves.
Yes, I'll be adding these to my carry along spare parts. Thanks

[Bill Pape]

What about the tag??

[Tim T.]

We'll start here.

Typical suspension drawing. You may have a better one in the Blue box.

Pilot valve specification sheet. Just to see what it looks like.

Photo of yellow top Clippard valves on my coach. Air inlet and air supply=same thing.

Drawing of electrical circuits for suspension and tag dump.

In a little while I'll try to add some explanation.

[KCSS]

Double ended Clippard valve on mine - - - - - on yours ?
Defective Williams dump valves ?

[Tim T.]

Gunner,

We can do quite a bit of troubleshooting to narrow the problem down if you want to. A volt/ohm meter would be handy if available.

There are 2 Clippard valves in your photo and in mine.

The Clippard valves are the under(above) the little yellow caps with the wires running to them.

They are separated and screwed onto a manifold that you see between them.

In your photo, and mine, the air comes in the single 1/8 in. line that you see on the right side. That is AUX air pressure.

The clippard valves are like little on and off switches for air. In this case, they are normally off until a current is supplied to them. No current=no air passing through.

When activated, the clippard valve will open allowing air to pass through.

The clippard valve on the top will pass air through to one of the outlets on the left side.

The clippard valve on the bottom of the manifold will pass air through to the other outlet on the left.

One of the clippard valves activates (controls) the tag axle dump.

The other clippard valve activates (controls) the suspension dump for the drive axle (both sides) and the steer axle.

One clippard for the tag and one clippard for the rest of the suspension.

The easiest way to proceed is to first determine if current is flowing to the clippard valves and which one activates the tag axle.

With the coach air pressure up, the tag axle switch "up" and the suspension switch "up".

First test.
1. Use the dash switch to dump the air in the tag axle. Does the dash gauge show the reduction of air pressure in the tag axle?
2. Next use your volt ohm meter (set DC volts) to probe the wires going to one of the clippard valves. One or the other of the clippard valves should show about 12vdc across the terminals. If we did this right that should be the clippard valve for the tag axle. Note which one that is.
3. Next remove the air lines on the left side of the manifold one at a time until you determine which port on the manifold has air pressure. The one with air pressure should be the air port and line that activates (controls) the tag axle. Note which one that is. I used masking tape.

If you got to here, we're making progress.

Do you want to continue the troubleshooting process?

[atckip]

I don't know about Gunner, BUT I can't wait for the next block...this is good stuff!

[TOPHAT1]

Thank you, Tim T. Yes, Let's progress!

First, I have electrical voltage on the top section of the Clippard Valve of 12 volts with the Suspension Dump switch set for dump (no voltage at the lower Clippard section)
Second, with the Tag Dump switch set to dump, (Suspension dump switch has been set to UP position) the lower section of the Clippard now shows 12 volts and the upper section of the Clippard shows no voltage.
-- Resistance reading is 217 ohms for the top section and 216 ohms for the bottom section of the Clippard valve.
Third, With the Tag Dump switch set to dump, the port for the lower air line (on side with two air lines) passes air out the port.

Awaiting next steps!

[Tim T.]

Lets verify what we know now, then we'll do the next test.

With the coach aired up, the suspension dump set to "up", the tag set to "up".

Setting the tag to "dump" should have started the tag pressure (shown on the dash) to start lowering. The lower Clippard valve should show voltage (about 12VDC) and the lower port on the Clippard manifold was passing air.

Is that correct? If not let me know.

For the next test, air up the coach again. The AUX pressure (probably the gauge in the wet bay) will have to be to be up (90psi or better) also.

With the Tag dump switch to "UP".
With the Suspension switch set to "UP".
And with the AUX air pressure built back up.

Second test:
1. Leave the tag switch set to "up".
2. Set the suspension dump switch to down/dump.

After 10-30 seconds take a look at the tag pressure gauge. Is the air pressure dropping?

Test the voltage at the upper Clippard valve.
Test the voltage at the lower Clippard valve.

We are expecting voltage across the terminals on both the upper and the lower Clippard valves. Bluebird has a circuit to energize both Clippard valves using just the "Suspension Dump" switch.

Do you have current at both Clippard Valves?
If yes,
Remove the air lines on the left side of the manifold one at a time until you determine which left side port on the manifold has air pressure.
Do they both have air pressure (passing air) or just one?
If just one which one?

Let us know.

[TOPHAT1]

Tim, a little problem here. while checking the upper clippard valve connections I shorted the connections and now can't find the fuse that is blown - I have checked P1A1 and P1C4 visually and with a DVM. Any suggestions on where to look?

[Dave Stokes]

Try SK32 in the lower front dash. That's my Suspension dump valve fuse.