The Challenging Part...
And Why We All Should Have an IP Gauge
- As recommended by VDH experts, the IP pressure on a DAAM should be set at 140 when the regulator is pressurized on a 300 psi tank. This is an expert refinement on what the service manual says... Which is to set the IP to 110 when the regulator is pressurized on a 2250 psi tank. It ends up being the same setting when you check it at both pressures afterwards BUT... Setting it while at the low pressure end gives finer control.
- On my Faux Kawasaki, I could not get the IP gauge needle to hold still. The HP seat looked like a brand new one though with a slight impression where the orifice contacts it. Anyway, I swapped it out for a brand new VDH seat I had in my spare parts collection. Results were still not good. So I re-faced the original seat with first 600 grit and then 1500 grit emory paper against a flat surface. This improved things a bit but the needle on the IP gauge was still creeping up a bit.
- Finally, I inspected the high pressure orifice up close and well lighted. Sure enough there were some scratches. So, I used 0000 fine steel wool and a new pencil eraser to CAREFULLY polish the orifice. This completely solved the leaking HP seal (and creeping needle of the IP gauge).
- The importance of the IP gauge... I could not have detected the leak in the HP seat without the IP gauge. I actually sprayed soapy water on just the nozzle when it was pressurized and I saw no bubbles... I could not see the leak that way. So the IP gauge is not just for setting the correct pressure. It's also a valuable diagnostic tool.