What is this thing?

[msksann]

Just to correct my previous post, I have found 2 Pressure Protection
Valves, (I do not have the bulk oil fill), and they are used in the
Ridewell air spring suspension system, not the air brake system. I am
unsure if they regulate the air pressure, or protect it from air loss,
or perhaps either or both, depending on how the ports are connected(?)
The specs say that the valve opens at 65psi, and closes at 45psi.
I started another thread under 'Pressure Protection Valves', to share
my expirence with the forum, and perhaps clear this up.
I do believe the diaphragm material is hardening and failing...

Michael Kramer
86 PT-40 8V92
San Dieg0,CA
--- In WanderlodgeForum@yahoogroups.com, "msksann" <msksan@...> wrote:
>
> Ryan:
> It is a Pressure Protection Valve. There should be some part numbers
> located on the 'cap', which, in this picture, is located underneath.
> It is probably the same ones used between the air tank and the spring
> brakes. Those are Midland part #N15759C (N157590) BB part #0522508.
> This has been replaced by the Haldex KN31000, available at napa for
> aprox $38. Or online for less:
> http://tinyurl.com/24ngm4
> I do not have the bulk oil fill on my Bird, so I can not check, but I
> had the diaphragm rupture on one of mine last week, (for the drive
> axel spring brakes). It opens at 65psi, and closes at 45psi, and it
> protects the air system from loss of pressure. On the 3 used on the 3
> axels, I believe the application is different, they keep us from
> releasing the brakes until we have at least 65psi, and close down if
> air pressure drops below 45psi(?) Perhaps someone else will jump in
> here and confirm this applications use, since a failure could be
> critical(?)
> I begin to suspect that the diaphragm material is cracking in all of
> them from age(?)
>
> Michael Kramer
> 86 PT-40 8V92
> San Diego, CA
>
> --- In WanderlodgeForum@yahoogroups.com, "Ryan Wright"
> wrote:
> >
> > Picture here: http://www.ryanwright.com/tmp/thing.jpg
> >
> > What is this thing? It's on the right side of my engine, tied into my
> > air system. It's leaking air like a sieve, on all sides where the
> > upper and lower pieces meet. I'd like to either replace the seal,
> > rebuild the thing, or replace it all together. But I need to know what
> > it is first.
> >
> > -Ryan
> > '86 PT-40 8V92
> >
>