Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Jim McNeece on December 15, 2013, 12:06:49 pm

Title: Possible HWH Solenoid Replacement Plungers
Post by: Jim McNeece on December 15, 2013, 12:06:49 pm
Faced with having to replace some or all of the HWH leveling solenoid valves due to desiccant powder contamination, I have been searching for an alternative to purchasing new solenoids at $109 each.

HWH will rebuild a solenoid for a maximum charge of $76.50 each plus shipping.  Still more than I want to spend since I believe any problem I expect to find can be solved by simply replacing the solenoid plunger (I expect desiccant powder has accumulated on the plunger seats, adversely affecting their sealing ability).

Others have reported leaking solenoid plunger seats resulting from various causes.  One person, can't remember who, reported that he used a lathe to successfully resurface the plunger seats.  A guy, Richard, over on the Newell Guru's forum removes the seat material and replaces it with RTV of the correct hardness (Shore A Durometer reading of about 72, he reports).

I asked HWH if they would sell just the plunger, but they said no. 

So, off to the Internet.

After looking at hundreds of pictures, I decided that a Skinner replacement plunger V5-207-N available from these nice folks Inventories in Stock by Oemsurplus911.com (http://www.oemsurplus911.com/skinner/skinner_parts.htm) would work.  I bought 6 for $17 each (no returns) for initial testing.

A comparison between a new HWH plunger (I took apart a new solenoid I had purchased this summer while at HWH) and the replacement is shown in Photo 1.  They are virtually identical except for the seat diameter.  The HWH seat is 0.3" while the replacement's seat is 0.2".  This feature limits the replacement to use on the small orifice (3/32") solenoids (there are two large orifice, 5/32", solenoids used for tag dump).  I can live with that.

The dimensions (inches) are:

                  HWH      Replacement
Stem dia:    0.441            0.442
Length:      1.170            1.185
Flange dia:  0.540            0.610
Seat dia:      0.30              0.20

The seat material is black on the replacement plunger, but seems about the same hardness as the HWH.

I built a test jig that simulates an HWH manifold (see Photo 2).  I tested one of the replacement plungers in a new HWH solenoid up to 150 psi with no leaks.  I, also, switched the solenoid open and closed a number of times, still with no leaks.

I have no idea if these replacements have the durability (or lack thereof) of the HWH plungers, but I am willing to give them a try.  I ordered more so I can replace all but the two large orifice solenoids.

Use this information at your own risk.  I am not endorsing use of the replacements.  I'm just willing to be a guinea pig.
Title: Re: Possible HWH Solenoid Replacement Plungers
Post by: Tim Fiedler on December 15, 2013, 12:12:37 pm
NICE!

Jim, you didn't happen to be an engineer did you?

Now all you need is John H's pit.....
Title: Re: Possible HWH Solenoid Replacement Plungers
Post by: Roland Begin on December 15, 2013, 12:31:46 pm
Isn't the internet great...Whatever did we do before this resource?

Roland
Title: Re: Possible HWH Solenoid Replacement Plungers
Post by: Caflashbob on December 15, 2013, 06:40:31 pm
Isn't the internet great...Whatever did we do before this resource?

Roland

Spent more money on less quality services
Title: Re: Possible HWH Solenoid Replacement Plungers
Post by: Rick on December 15, 2013, 08:48:57 pm
Jim,
Nice write up! ^.^d

For what it's worth, here are the markings off of one of my HWH solenoids

Solenoid markings from my 1995 U-300


               AV
AC  22/50      24/60
DC  12VDC
      AUTOMATIC VALVE
      NOVI, MICHIGAN


Additional research required to find an alternate supplier

Rick