service manual #25

[Poppy19]

I downloaded service manual #25, and need sections 4 and 5, but it ends at 3A.
Is there somewhere I can get the rest of the manual?

I want to troubleshoot my fuel pump.
I have a 1996 stern drive bowrider with a 4.3 carbureted engine.

[mmwjr]

Interesting, I never noticed that before. Have you tried Googling for Mercruiser manual #25?

[Poppy19]

Well not using those exact words, but I am leery of downloading manuals from unknown sources. So I thought I would ask your recommendation first.
Poppy

[mmwjr]

Being a 1996 4.3 it should have an electric fuel pump. What is the issue you are experiencing?

[Poppy19]

There is power directly from the battery to the pump, but it doesn't pump when we turn the ignition key.

[Poppy19]

It appears the the boat had been underwater, at least half way up the engine.
The electric fuel pump also sits on top of an approximately one quart container. It seems to have a thin oil in it, but has some white floating on top, I imagine that it is milkshaked water and oil.
I have no idea what that is, or what it is for.

[Poppy19]

In another thread, it was posted that the fuel pump has a cut off switch when the oil pressure sensor, senses no oil pressure. I guess similar to the inertia cut off switch in cars. I don't know where the oil pressure sensor is, nor how to test it.

The pumps I have seen online look very different from mine. I can't get to the boat today to post a picture of it. Hmmm, maybe my son can.

[Poppy19]

Oh snap!
My fuel pump looks exactly like this:

Apparently it is the trim tab pump, and reservoir.

So now I need to locate my fuel pump.

Thanks for your help so far

[mmwjr]

Originally Posted by Poppy19

Oh snap!
My fuel pump looks exactly like this:

Apparently it is the trim tab pump, and reservoir.

So now I need to locate my fuel pump.

Thanks for your help so far

This is a picture of the drive trim pump not the trim tab pump. The fuel pump should be on the front of the engine block, about the size of a Red Bull. The fuel pump gets power from the starter solenoid when starting and once started power comes from an oil pressure switch. Does your engine start then die in a minute? If so the oil pressure switch is bad.

[Poppy19]

Thanks Mike,
I guess the drive trim pump will raise and lower the outdrive?

I'm hoping that the front of the engine block is the side that is closest to the interior of the boat, not nearest the transum. Should be easy to swap out if necessary.


It will run for a moment on starting fluid but there's no fuel in the bowl, or at least the accelerator pump doesn't pump fuel.

[mmwjr]

Yes that pump trims up and down the outdrive. The fuel pump should be to the left and slightly above the engine circulating water pump.

[Poppy19]

Thanks Mike,
My son wanted to take an OFF Day today, perhaps we'll get a look at it tomorrow.

[mmwjr]

Originally Posted by Poppy19

Thanks Mike,
My son wanted to take an OFF Day today, perhaps we'll get a look at it tomorrow.

Enjoy your day off.