Thumping SRV

[londonrain]

Replace two thumping SRV valves this week on the same job. The PGV tops fit the SRV valve body so it is an easy fix...After thinking about the problem I believe it is the solenoid not opening all the way.

Pulled out my calipers and measured the solenoid hole on both valve tops. The SRV is 2/100th" smaller than the PGV... Same measurements on a few different valve tops, all the same.

[FIMCO-MEISTER]

Interesting. Is the thumping starting at shut down?

[londonrain]

Originally Posted by FIMCO-MEISTER

Interesting. Is the thumping starting at shut down?

One was at start up and the other was at shut down....

[Mike Leary]

Originally Posted by londonrain

One was at start up and the other was at shut down....

I've had "thumping" too..always traced to high pressure.

[londonrain]

Both valves use the same solenoid, diaphragm and diaphragm ring.....

[Wet_Boots]

Opening thumping is kind of maddening. Almost like some oscillation or resonance is going on.

[PurpHaze]

I run into "closing thumping" on rare occasions after installing a new valve. After it's been actuated a couple of times and the Flow Control is set where I want it... it goes away.