How do these fuel line taps work? (picture)

[CaptainBob]

I have two fuel tanks in the boat I just acquired which feed one filter as pictured. The 'T' has fuel from each tank coming in on the arms, through a small 'tap' and then the lines join before entering the first filter.

I assumed that those fuel tap things would be open when in-line with the pipe and closed when perpendicular but I went to turn off one tank and found I could rotate the handle a few times either way, until it wouldn't go any further.

Are they in fact gate valve type things?

Sorry for over long explanation.

Thank you!

 

[rogerthebodger]

That's a needle valve and will take several turns to fully open or close.

They can be used to control the flow is so needed. I have a similar valve as a water drain on my fuel filters.

 

[ghostlymoron]

Might be a good idea to fit a small ball valve in each line for a quick shut-off. You can retain the needle valves for regulation if required - although I'm not sure why you would want to.

 

[VicS]

Roger is almost certainly right but needle valves are an odd choice I would have thought.

I'd consider replacing them with ball valves but if they work don't fix what is not broken.

 

[Caer Urfa]

Hi Bob
Agree with what all have said above, I fitted ball valves in a simular installation layout, as also said much quicker to switch over fuel supply.

Mike

 

[CaptainBob]

Great stuff, thank you! System also has remote operated fuel shut-off right at the tanks so take your point that ball valves might be preferable, but as Vic said, think I'll leave it as is for now. Thanks again.