M939 series diffs

[charlesmann]

One port is inlet. One outlet. One is exhaust. Exhaust has to expell or the fan will stay pressurized

Correct, i figured that much. The solenoid is engraved, 1, 2 and 3. As previously stated, ports 2 and 3 are, with no elec applied, out of the box, are ported/linked together. I blew in port 1, had no air flow, i took another breath, blew into port 2, and heard air out of port 3. I blew once more in port 3, and heard/felt air coming out of port 2.

In addition, port 3 is a cap, like a compression fitting cap, but is sealed at the base with a rubber washer, and threaded at the top for a 1/8 npt fitting.

 

[simp5782]

1 will be inlet when the solenoid is energized the lot should open letting air go to #2. It will close off the vent from #3. When off it closes 1 and connects 2 and 3 to exhaust

 

[charlesmann]

One port is inlet. One outlet. One is exhaust. Exhaust has to expell or the fan will stay pressurized

Thanks.