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Coach 647, 2003, 45 ft. 60 series detroit
Front hieght control valve leaking, anyone have knowledge on replacing. Mine is in a very difficult  location will be hard to do on back.
Anyone have a part #.
Thank you, James Price

[Richard]

James,

I think you will find a standard Hadley height control valve will work.

A couple of cautions when replacing the front height control valve. Of course the coach must be cribbed or on heavy jack stands before getting under there. In theory the six pack should keep air pressure in the bags with the coach turned off, but as a belt and suspenders approach I lower the coach onto the supports and exhaust the air from the bags. That provides protection in two ways. One, it proves the support will hold the coach. And two, it protects me against an accidental discharge of air from the air bags. You may say that is overkill, but I once broke one of the fittings from the six pack to the airbag while working on the steering gear box. I still soiled my pants when it happened but the coach was sitting on the supports and didn’t move an inch.

Measure the ride height very carefully. A small change in ride height on that suspension produces a dramatic change in toe in. You want to set the ride height as close to the as found condition as you can, or plan on a realignment.

Notice how the vertical rod is attached to the sway bar. It works BUT because the system is way more sensitive than the rear setup, the shorter arm MUST be used on the height control valve. Take the arm off the old one and use it on the new one.

And, a very small change in the adjustment of the valve results in a large change in the ride height because of this setup.

Lastly, when adjusting a ride height control valve, you must lower the coach all the way on the air bags and allow the HCV to raise it. If you simply have it raised all the way for access, put it in travel to allow the HCV to lower, you will not get a consistent measurement in ride height. You can drive yourself crazy if you don’t do it the correct way. The valve has a bit of hysterisis (slop) in it’s internals that cause this to happen.

[hypoxia]

FWIW, 1482 has Barksdale 52321 ride height valves.  The difference between different dash numbers, ie 52321-Q136 may be the arm length and shape as well as the bolt positions.  The valve parts are installed using red thread blocker so you have to heat a part before removing it to reposition.  Just enough heat to soften the thread blocker.  As Richard suggested, use the existing valve arm.  Newell valves are proprietary so I cannot purchase that specific part number anywhere else but instead I just get another Barksdale 52321 valve & modify it.

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Richard and Jim thank you both for this information, I am fairly new to the Newell coach but i am learning a hole lot about coach 647, from the GURUS, and Newell service techs.
Thanks again James Price

[Latitude 28]

James,

I think you will find a standard Hadley height control valve will work.

A couple of cautions when replacing the front height control valve. Of course the coach must be cribbed or on heavy jack stands before getting under there. In theory the six pack should keep air pressure in the bags with the coach turned off, but as a belt and suspenders approach I lower the coach onto the supports and exhaust the air from the bags. That provides protection in two ways. One, it proves the support will hold the coach. And two, it protects me against an accidental discharge of air from the air bags. You may say that is overkill, but I once broke one of the fittings from the six pack to the airbag while working on the steering gear box. I still soiled my pants when it happened but the coach was sitting on the supports and didn’t move an inch.

Measure the ride height very carefully. A small change in ride height on that suspension produces a dramatic change in toe in. You want to set the ride height as close to the as found condition as you can, or plan on a realignment.

Notice how the vertical rod is attached to the sway bar. It works BUT because the system is way more sensitive than the rear setup, the shorter arm MUST be used on the height control valve. Take the arm off the old one and use it on the new one.

And, a very small change in the adjustment of the valve results in a large change in the ride height because of this setup.

Lastly, when adjusting a ride height control valve, you must lower the coach all the way on the air bags and allow the HCV to raise it. If you simply have it raised all the way for access, put it in travel to allow the HCV to lower, you will not get a consistent measurement in ride height. You can drive yourself crazy if you don’t do it the correct way. The valve has a bit of hysterisis (slop) in it’s internals that cause this to happen.

Richard,
Is the Hadley valve original equipment from Newell?

[Richard]

No idea about the Hadley as original. I am just going by what is on mine. Who knows if it was replaced sometime in the previous 24 years…………………

There is nothing magic about the specific valve. There is something super critical in the arm length. If you use the standard arm length, it will NOT work because the vertical linkage arm is mounted on the sway bar. The setup uses the rotation of the sway bar to actuate the HCV via a second arm attached to the sway bar. Both of these arms are definitely Newell engineering specials.