MK4 – Replacement Regulator Diaphragm and Seat Assembly (MKIV)

Complete Diaphragm, Seat and Seat Cap assembly.

Unlike some other cheaper regulators these seat and seat cap assemblies come as a completely encapsulated (enclosed unit).  On the base of the seat and seat cap assembly you can see we use an additional sintered filter.  This reduces the chance of contamination and reduces the chance of pressure creep.  The fully encapsulated seat design also means that if the regulator is serviced in an environment that is not completely clean you have less chance of getting contamination into this sealed assembly

MK4 – Regulator Replacement Diaphragm and Seat Assembly

The sintered valve is compatible with the MK3 regulator. The diaphragm itself is not compatible with the MK3 Regulator as it is much larger.

These are high-quality parts made for a high-quality regulator.

The main reason you might replace these parts is because:

1. You have gas leaking through your diaphragm. (this is extremely uncommon)
2. The gasket on around the edge of your diaphragm is worn out. (this is also extremely uncommon)
3. You have a pressure creep issue.  (this is the most likely need to purchase this assembly)

Regulator Pressure Creep
Regulator creep is normally caused by contamination getting into the seat and seat cap assembly of your regulator.  This is normally a result of gas leakage over the seat and seat cap assembly causing high-pressure gas to leak into the low-pressure gas side of the regulator.  As this happens your regulator will “creep” up in pressure until the pressure relief valve activates.  Replacing these parts in your regulator will fix this issue and only takes a few minutes to replace.