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Alright. This is working, but I still wonder how.
my diesel lines are higher than the engine and the tank, and even than the secondary filter.
See attached picture.

Now, When I change the racor filter, I introduce air in those tubes, before and after the filter, I understand that.
I have a manual lift pump that I use for around 1 minute, without noticing anything. I bleed my engine at 3 points, but do not really see any air bubbles, it is pretty much fuel.

And it works. This is a Westerbeke 40.

How does the fuel circulate through the lines to the fuel pump without a lift pump ? that's a mystery to me.
Anyone cares to explain ?
Appreciated.
 

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Hunter 34
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If the engine injector pump is lower than the top of the fuel then it will act like a siphon, possibly there is some "draw" from the injector pump also ,but I don't know
 

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Yanmar 4JH, no lift pump. None. Nada. Zilch.

While I have since changed things about, adding a day tank for other reasons, the engine ran fine when drawing from the bottom of a tank at least 5-feet BELOW the Racor.

Just saying.
 

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Yanmar 4JH, no lift pump. None. Nada. Zilch.

While I have since changed things about, adding a day tank for other reasons, the engine ran fine when drawing from the bottom of a tank at least 5-feet BELOW the Racor.

Just saying.
Same here with a Yanmar 4JH3-HTE. That said, I am adding an electric in-line pump to facilitate system bleeding when I change filters and also so I can polish my own fuel without running the engine.
 

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Mechsmith
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Some setups include the lift pump within the injector pump. ( two or even three stage pump) If your priming pump is located on the injection pump that is probably what you have. There are many different possible ways for the manufacturer to solve the problem of pressurizing the injector pump which is necessary in order to make one work.
 

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Señor Member
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thevdeub,

What engine do you have?

I'm no diesel mechanic, but I've turned a wrench or two. I'd bet that you've got a low pressure (lift) pump there somewhere. A parts and/or service manual would either confirm or disprove my thought.

BTW: Your Racor unit is a 500FG; the 2010TM is the filter element. There's a check valve inside the housing that keeps fuel from back-flowing when you open it up. If yours is losing fuel back down the lines you might want to dig a little deeper into the unit. MaineSail has a pictorial on a rebuild on his website.

Another thing to consider (if you are concerned about fire safety) is that the FG isn't rated for engine spaces since it doesn't have the metal heat bowl. The good news is that you can retrofit a metal bowl for a whole lot less that a 500MA is gonna run you.
 

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Señor Member
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My engine is a Westerbeke 40. I have the manual and did not see any trace of lift pump.
The W40 is almost identical to the Perky 4.107 & 4.108 (which I'm kind of familiar with.) The lift pump is on the starboard side of the engine, mounted below the fuel filter.

If you want a visual, take a look at the 3d and 4th pics in this post. The pump is that piece on the access plate on the left below the opening for the intake manifold. The pump is driven by a lobe on the cam shaft.
 

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Dirt Free
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This is helpful. Do you mind to elaborate ?
Because it took 14 posts to determine that there actually is a lift pump. This fact is elemental and anyone with any knowledge of these small diesels should have known. All posters up to that point (IMHO) would benefit greatly from a basic diesel course.
 
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