Non return valve for diesel line

Oily Rag

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I'd like to add a booster pump to ensure delivery of fuel with a low tank level. But I don't want the pump running all the time the engine is running, so I'd like to fit it in parallel with the existing fuel line. Obviously, I need a non return valve to prevent the pump sending everything back to the tank.
Can anyone recommend a suitable valve type?
 

PaulRainbow

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If you must fit a pump, fit an inline pump, such as a Facet, that allows the fuel to flow through the pump when it's not running. No need for parallel lines and non-return valves. I'm sceptical that you need one, are you sure you weren't just low on fuel and drew air in ?
 

Oily Rag

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If you must fit a pump, fit an inline pump, such as a Facet, that allows the fuel to flow through the pump when it's not running. No need for parallel lines and non-return valves. I'm sceptical that you need one, are you sure you weren't just low on fuel and drew air in ?
Many thanks. I didn't know there were such pumps. I need to broaden my experience!
When I lost power, I had at least half a tank, but you're right, I may just have drawn air. The takeoff is not on the tank centre line, so one tack is better than the other for motor sailing. I was on the other one.
Also, when I had to reprime, I could have done with a pump to speed things up.

Now off to Google Facet! ?
 

TernVI

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It doesn't take much 'sloshing' for the engine to take a gulp of air when motorsailing.
Been there, it knocks your faith in the engine for a bit.
 

RichardS

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My 18 years’ experience of the Beta’s Kubota pump is that it can lift far higher than Beta advise.
I'm somewhat unsure about the engineering logic. :unsure:

If there is a potential problem with fuel sloshing about when heeling and the tank level is low such that air can occasionally be sucked into the dip pipe, then surely installing a more powerful lift pump is likely to suck in a bit more air rather than less as, in that brief period when the bottom of the dip pipe is dipping into air, the more powerful pump will be sucking that bit harder?

Richard
 

Oily Rag

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It doesn't take much 'sloshing' for the engine to take a gulp of air when motorsailing.
Been there, it knocks your faith in the engine for a bit.
Yes, but it makes you think of the effective volume of the tank. Unlike a car, you can't expect to run it dry!

And experimenting to find the effective level would mean a lot of repriming of the fuel system. Not easy doing it by hand.
I should perhaps stop over thinking it and just fit a squeeze bulb and carry an extra jerry can.
 

[185615]

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I'd like to add a booster pump to ensure delivery of fuel with a low tank level. But I don't want the pump running all the time the engine is running, so I'd like to fit it in parallel with the existing fuel line. Obviously, I need a non return valve to prevent the pump sending everything back to the tank.
Can anyone recommend a suitable valve type?
I have bought some from here: https://www.ssldieselparts.co.uk for a fuel polisher I built.
A good company in the outer hebrides but great to deal with.
 

LittleSister

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As Paul says, you don't need a non-return valve if you buy an appropriate pump. That said, you can buy Facet pumps both with and without a non-return valve incorporated in them. A potential advantage of having such a valve in the pump is that when you change the fuel filter the fuel will not drain back to the tank (which I assume from what else you say is below the engine level).
 
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