electric fuel pumps for Lehman 120

[CaptRob73]

I'm considering converting my 120 Lehmans to electric fuel pumps. Please tell which pumps y'all are using if you've converted Yours.

I heard about Walbro and Facet pumps but not sure on the pressure requirements.

 

[Max1]

When I bought my 120 Lehman equipped trawler, the previous owner(s?) have already switched the fuel pump to a simple automotive pump. I haven't touched it and have used it all summer without a hitch. I also purchased a second pump just in case the one in the boat crapped out, but so far it's been fine.

The pump is wired into the ignition so once the key is turned to the "on" position, the pump comes on.

Just FYI, I installed a switch on the ignition panel on the dash that can turn off the pump "just in case". Also, out of curiosity, I have tested the operation of the engine while underway by switching off the pump "just to see what would happen". To my surprise, the engine kept on running without a drop in power or RPM. Nevertheless, I just leave the pump running at all times when the engine is on.

PS- the pump is located between the fuel tank and the first Racor filter.
Fuel system is as follows:
Tank--> Fuel Pump --> Filter1 --> Filter 2 --> Injector pump

 

[Barking Sands]

I have this Facet pump
https://www.ebay.com/itm/Solid-Stat...2349624.m46890.l49286&mkrid=711-127632-2357-0

 

[PM]

I had an electric fuel pump on a gasser I owned. When I was trolling the constant "click" drove me nuts so I would shut it off. didn't need it at low speed.

pete

 

[CaptRob73]

When I bought my 120 Lehman equipped trawler, the previous owner(s?) have already switched the fuel pump to a simple automotive pump. I haven't touched it and have used it all summer without a hitch. I also purchased a second pump just in case the one in the boat crapped out, but so far it's been fine.

The pump is wired into the ignition so once the key is turned to the "on" position, the pump comes on.

Just FYI, I installed a switch on the ignition panel on the dash that can turn off the pump "just in case". Also, out of curiosity, I have tested the operation of the engine while underway by switching off the pump "just to see what would happen". To my surprise, the engine kept on running without a drop in power or RPM. Nevertheless, I just leave the pump running at all times when the engine is on.

PS- the pump is located between the fuel tank and the first Racor filter.
Fuel system is as follows:
Tank--> Fuel Pump --> Filter1 --> Filter 2 --> Injector pump

Thanks for the info.

I was curious if they would run with no pump just using head pressure of the tanks. Also, they might not with a low tank level or rough conditions.

 

[alormaria]

He may still have the original pump in line. They usually don't mind the help.

 

[Mike GB32]

I used a Walbro FRB-13 on my Lehman. Made for marine applications. Works perfectly.

 

[Doug]

He may still have the original pump in line. They usually don't mind the help.

Is this the way most people install them, with the mechanical pump in place? Or is the preferred method to remove it?

 

[Mike GB32]

I removed my mechanical pump and blocked off the mounting flange. Speed shops sell a plate that was made to block off the mechanical pump on a big block Chevy engine.

edit: I should have added that the big block Chevy plate will fit the Lehman perfectly.

 

[Max1]

Is this the way most people install them, with the mechanical pump in place? Or is the preferred method to remove it?

The mechanical pump in the 120 is a cam operated pump that is integral to the engine block. The problem with these pumps is they use a diaphragm operated by the cam to pump fuel. If the diaphragm tears, you get fuel leaking into the crankcase and contaminating the engine oil. If your mecahical pump is inop and you are going with an electric pump, the best option is to bypass the mechanical pump and seal off the fittings.

 

[SIBERNUT]

I am re-plumbing the fuel system on a 135 Lehman. Racor was before electric pump, but I'm thinking it may suck air if there's a pinhole leak vs Racor after pump. Easier to see if a leak. Comments?

 

[rgano]

I am re-plumbing the fuel system on a 135 Lehman. Racor was before electric pump, but I'm thinking it may suck air if there's a pinhole leak vs Racor after pump. Easier to see if a leak. Comments?

One thing about putting the pump after the Racor is the fact that a vacuum gauge will register while if the rump is before the Racor, not so much. Might as well trash the vac gauge if placing the pump before the Racor. Then how do you get any information about the status of the Racor's filter? However, if the pump is after the Racor, there are several places on the Racor which can contribute to air injection.

 

[Max1]

I am re-plumbing the fuel system on a 135 Lehman. Racor was before electric pump, but I'm thinking it may suck air if there's a pinhole leak vs Racor after pump. Easier to see if a leak. Comments?

My pump is before the filters.

Tank-->Pump-->Filter1-->Filter2--->Injector Pump.

 

[Mike GB32]

Sibernut- Racor's installation instructions recommend mounting the 500 series before the pump. I'm not saying you HAVE to, but that is what they recommend.

https://www.parker.com/content/dam/.../15335_Rev_G_(500_Series_Marine_Turbines).pdf

 

[SIBERNUT]

Tks

I searched here & online, appreciate you coming up w/that!

Now i need an answer to what the "day tank" is under the counter in my head.

 

[socalrider]

I used a Walbro FRB-13 on my Lehman. Made for marine applications. Works perfectly.

Me too. I removed and blanked off the mechanical pumps. Two seasons and no issues at all. My pumps are between my primary and secondary filters.

 

[Chuck34]

I'm considering converting my 120 Lehmans to electric fuel pumps. Please tell which pumps y'all are using if you've converted Yours.

I heard about Walbro and Facet pumps but not sure on the pressure requirements.

Best to call Brian at American Diesel and ask what you should be using and buy from him. If you are not familiar with American Diesel…they wrote the book on the marinized Lehman. No one knows it better.

 

[CaptRob73]

my set-up

My set up is 30 micron racor - pump - 2 micron racor with vac. gauge on the 30 micron. I feel you should have a filter after the pump in case it has a problem and send out debris.

 

[C lectric]

There is another train of thought about pumps ahead of the filter aside from the defeating of any vacuum guage.

Pumps can force water through a filter element that in suction mode the water would be stopped.

There are pressurized filter system BUT that filter is usually preceded by at least one filter ahead of the pump. Between the tank and the pump.

 

[PM]

Why replace the mechanical pump anyway?

pete

 

[catalinajack]

Why replace the mechanical pump anyway?

pete

Because if the diaphram on a mechanical pump fractures it will fill the lube oil sump with diesel fuel and, if not discovered, will destroy your engine. How likely is that? Not very likely, but, when it comes time to bleed the system of air for whatever reason, you won't have to actuate the lever on the mechanical pump 100 times to bleed air, a wonderful task if the pump is on the outside of a twin engine boat.

A Walbro will supply fuel at the same PSI as the mechanical pump so there is absolutely no reason not to use one despite what American Diesel might have to say.

 

[Barking Sands]

There is another train of thought about pumps ahead of the filter aside from the defeating of any vacuum guage.

Pumps can force water through a filter element that in suction mode the water would be stopped.

There are pressurized filter system BUT that filter is usually preceded by at least one filter ahead of the pump. Between the tank and the pump.

If the flow rate and pressure differential across a filter membrane are the same how can it force water through the membrane?