dual diesel fuel pumps ?

[stw]

Currently redesigning my fuel supply system.
My intention is to install a fuel pump between the Racor primary fuel filter and the engine.
Is there any harm in this set-up? pros? cons?

Engine = https://www.yanmar.com/marine/product/engines/3ym30ae/

In-Line Fuel Pump = https://reversopumps.com/gp-301-12h/

Primary Fuel Filter = https://ph.parker.com/us/en/marine-f...series/500ma10

[Cwens]

4.5 GPM pump seems awfully big for the job.

[Sailorman Ed]

Me thinks your filter is way too big. Look for a Racor 500 for that little Yanmar.
Also, search for a Facet electric pump, should be about $60-70 and will pump plenty for that motor. I have 2 of those Facet pumps, work great.

[stw]

thanks for your replies

- I am using the Racor 500MA as the primary fuel filter (maybe the link is misleading)

- I already own the Reverso fuel pump ...

Is there harm in having this fuel pump in-line between the primary fuel filter and the engine?

[Bill Seal]

The fuel pump on the engine can "suck" through a Facet pump valves, a non running gear pump will shut off the fuel.

[Searles]

Unless you have a pressure release valve and fuel return to filter or tank ,that pump is positive displacement gear pump way to much flow and pressure for your system ,a Facet pump will do it fine ,.⛵️⚓️

[Scubaseas]

29.5 psi is way too much for what is essentially a lift pump. 4 to 7 psi is more like what you need. You may start blowing seals on your injection pump if feeding it 4.5gpm at 29psi.

Nothing wrong using an electric lift or feed pump but use something more in line with your manufacturer's specs.

[Stewie12]

Why complicate life worth 2 fuel pumps.

[wingssail]

Our engine is below the level of the fuel tanks. Gravity feeds the lift pump.

However, we have a small 3-4 psi electric pump which can be switched on (for the heater, primarily) and it will feed the engine's lift pump if there is ever a need to do that. I can also bypass the lift pump and feed the engine fuel filter directly with the electric (never had to do that either) or prime the system if we've run out of fuel (however the Yanmar will usually self prime).

This arrangement is simple, provides redundancy, and the electric is rarely used.

[Stu Jackson]

The fuel pump belongs in-line between the primary fuel filter and the engine. It should not be before the primary filter. That's why they call it a PRIMARY filter.

[hpeer]

Walbro pump would be more appropriate. And I think with a higher reliability rating. You can call them and ask for advice on exact model to accomplish what you want.

I use these pumps as fuel transfer pumps from my main tank to my day tank through a Racor 500. Then the engine injector pumps from day tank to engine through a second Racor 500.


https://walbrofuelpumps.com/marine-industrial-fuel-pump

[RaymondR]

Originally Posted by Stu Jackson

The fuel pump belongs in-line between the primary fuel filter and the engine. It should not be before the primary filter. That's why they call it a PRIMARY filter.

Makes it easier to bleed the air from the system if it's between the fuel tank and the filter. My boat has one there just for system bleeding after filter changing.

[Tin Tin]

Originally Posted by stw

Currently redesigning my fuel supply system.
My intention is to install a fuel pump between the Racor primary fuel filter and the engine.
Is there any harm in this set-up? pros? cons?

Engine = https://www.yanmar.com/marine/product/engines/3ym30ae/

In-Line Fuel Pump = https://reversopumps.com/gp-301-12h/

Primary Fuel Filter = https://ph.parker.com/us/en/marine-f...series/500ma10

That is a fuel transfer pump for moving fuel from one tank to another not to feed the engine. As noted above a small cube type facet pump is all that is needed. Having an small electric fuel pump between the primary filter and the secondary filter on the engine is fine. A lot of Yanmars are set up this way as standard. Same for generators.

[sinnerman]

I would think that if you leave the mechanical engine-mounted lift pump installed on the engine, you run the risk of blowing out the pump diaphragm due to the higher inlet pressure from the electric pump feeding it.

A diaphragm failure would result in filling your crankcase with diesel.

These mechanical "lift" pumps are not designed to have high pressure on the INLET side of he pump...

If you are looking at a way to speed up /make easier the process of bleeding air out of the system (not having to sit there actuating the mechanical pump by hand for minutes on end), I have seen some owner install a hand priming bulb in the fuel line.

The bulbs used on outboard engine fuel tanks...


If you are going to install an electric fuel pump between the Racor and the engine, the best thing would be to entirely REMOVE the old mechanical lift pump and blank it off. (OR) just bypass the pump completely and connect your fuel line from the electric pump directly to the engine-mounted fuel filter.

I have an electric Facet cube fuel pump on my boat. It runs quiet and cool with negligible power consumption.

facet pumps:
https://www.pegasusautoracing.com/ad...SAAEgLaC_D_BwE

cheers

[stw]

thanks to each of you for sharing information

I could not find fuel line psi input limits for the Yanmar 3YM30AE ...
is 8 psi too much pressure ?