Forum Discussion

howardwheeler's avatar
Sep 27, 2020

Marshall changeover regulator doesn’t indicate empty tank

I have a fairly new (maybe one to two year old) Marshall Excelsior two stage propane regulator that has stopped changing the green sign in the upper bulb to red when the tank the lever points to is empty. It appears as though it is changing over to the other tank but definitely the bulb always stays green—-even with the tank removed! Is this fixable? What would cause this? If I’m not mistaken ( it’s been too long) I may have encountered this on my previous regulator, also a Marshall. Is my propane “gunky” and mucking up the signal bulb from being able to move up and down? What is going on? Anybody want to hazard a guess?
  • It could be oil in the propane. Mine does similar but it does not show red nor green. It does switch over.
  • Yes it is fixable. Replace it with a Cavagna brand regulator. Better accuracy, easier to read.
  • Does the Cavagna indicator work on a different principle than the Marshall and therefore not as likely to malfunction? Oil does seem to form in my propane lines.
  • If you fill at the same place I would find a new supplier. No I don't think any regulator is immune from being fouled with bad propane. I also recommend new Cavagna pigtails.
  • Indicator works off of cylinder pressure
    When pressure in cylinder drops to roughly 10# the regulator swaps to the other cylinder
    When you move lever the pilot valve allows full cylinder pressure in causing Red to move to Green indications

    Pilot valve is gumming up and wouldn't matter which regulator you have if propane supply is gummy
  • Check that the plastic cover over the r/g indicator has not been pushed down covering the space for the red to show.
    Art