Vacuum Gauge Installation Question

[Al - s/v Persephone]

I got a 1606 vacuum gauge kit for my spin-on Racor filter (R20P elements). It comes with _very_ generic instructions saying to "T" the line from filter output to engine fuel pump in order to sense the vacuum level in that circuit.

My Racor has 2 separate fuel outputs, 180 degrees apart (with fuel input fitting between them at 90 degrees). One output fitting goes to the engine, while the other (unused) one has a plug in it.

Since it looks like either output fitting would provide fuel to the engine, am I wrong in assuming that there is an internal direct connection between them that would allow me to directly plumb the vacuum gauge to the unused output and read the same vacuum level without T-ing?

Fair winds,
Al

 

[Stu Jackson]

Since it looks like either output fitting would provide fuel to the engine, am I wrong in assuming that there is an internal direct connection between them that would allow me to directly plumb the vacuum gauge to the unused output and read the same vacuum level without T-ing?

Al, theoretically using either one should, because the vacuum gauge is reading pressure, not flow.

If it was my boat, I'd loosen the housing off whatever it is attached to, remove the plug, insert the gauge, and start the fuel pump. If the gauge works, just slap the housing back where it was.

Only other consideration is view. On my boat, if I did that i wouldn't be able to see the gauge because of the location of the filter housing, and would have to put it on the same side as the fuel hose outlet with the T.

 

[Don12364]

Am looking at a brand new Racor 110A filter right now.
The two outlet ports are directly connected, as are the inlet ports also.
I see no reason not to connect the gauge directly between the pair of unused ports.

 

[Dan Johnson]

I have a "T"...

between my Racor and the lift pump. I have the gage mounted in a cockpit pocket with the fuel gage so I can keep an eye on it when under way with Yannie power.

 

[Benny]

Probably for a twin engine installation. Generally if there is no flow, there is no pressure so I would be inclined to say it would not work, but I don't know how are the outlets interconnected so I could not categorically ascertain that it would not. I think the point of location would be significant factor; you would want to locate the gauge where you can see it so it may be more convenient to "T" off the fuel line as per the instructions.