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Suntec bypass plug depth?

Brian26 Member Posts: 26
How far in is the bypass plug on a suntec a2va-3006 supposed to be installed? I put mine in as far as it would go and think I blew the pump. I noticed there is a small port on the side of where the plug goes. I might have gone in far enough to cover it. Does the plug just go level with the threads?


    EBEBRATT-Ed Member Posts: 13,427
    It goes in all the way until it is snugged up tight.

    Just remember he plug is removed for a 1 pipe system and installed in the pump for a two pipe system. The return line port must be connected free and clear back to the oil tank when the plug is installed and your running two pipe. Starting a burner with a closed return line hooked up two pipe will blow the pump seal
  • Brian26
    Brian26 Member Posts: 26
    It's hooked up to a tigerloop and the plug is in. I think the pump is shot even though it's new. With a pressure gauge hooked up to the nozzle line the pressure is erratic and the gauge flickers back and forth when I set it to 140 psi. It smooths out dead on when set to around 100 psi.

    Coupler and motor are new.

    I did powerbleed several times with the tank valve shut. Did too much vaccum maybe blow the seals? Maybe the tigerloop is bad?
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,128
    The plug goes in the bottom of the pump, in the return port, the same port as the return to the Tiger Loop-screwed all the way in. You shouldn't have to power bleed it.
    Also, make sure you have the right screw as there are 3 different sizes, depending on pump. I assume you use the one that came with the fuel unit.
    Don't forget to check the firomatic valve. If that's failed or mostly closed, that will run your vacuum up, possibly causing a pump seal failure.
    Flickering gauge is common if you don't use liquid filled gauges.
    I would double check to make sure everything is piped correctly.
    You can also grab Suntec's install manual online which shows how to check the pump (vacuum, pressure, cut-off) before calling it bad.
    EBEBRATT-Ed Member Posts: 13,427
    The pump may not be bad. The oil pressure should be rock steady. Check the pump out as Steve said. Normally the pressure gage goes in the bleed port