BF200 low pressure fuel pump

My stbd outboard starting losing power. When I checked the filter housing it was less than 1/3 full when running. When I squeezed the fuel bulb it filled up then slowly drained back down to less than 1/3. Does that sound like a low pressure pump going bad?

Based on posts on this site, it seems that different engines will maintain the fuel level in the LP filter at different levels - I have no idea why.

Provide more detail on "losing power." What is it doing? Losing rpm's? Gradually or suddenly, etc. etc. Under what conditions?

You can remove the LP fuel pump and test it by hand to see if it is pumping fuel and check for leaks. To get to it, you will need to remove the intake manifold. Then remove the two bolts that hold it in place. You can work the plunger by hand by exercising the plunger that sits on the cam. If exceptionally stiff or rough, replace it. If fuel leaks, replace it. When re-installing, use a new O ring with a light coat of grease.

The engine idles well and accelerates up to about 4000 then the RPMs drop off suddenly or the RPMs stay flat no matter how much throttle you give it. It will slowly lose RPMs or surge.

I'll check the pump. The bowl used to be about 2/3 full so the level change was a big indicator for me.

Again thanks for the advice.

Based on the added description, my initial thought is a fuel line restriction or air being drawn into the fuel line under high demand.

When the engine starts dropping off, have someone rapidly pump the primer bulb and see if it straightens out. If so, then a good possibility it's the low-pressure fuel pump.

However, before tearing into it, check a few other things first...

If you have an external fuel/water separator (which you should), when is the last time you changed the filter element? They do get clogged up over time. Same goes for the onboard LP fuel filter.

Check your fuel line where it goes into the engine compartment through that big black grommet. There are quite a few cases on this forum where corrosion has built up there and restricts the fuel line. Also check for a weak hose as it enters and exits the grommet - the constant flexing there can cause a weak point and a partial hose collapse under high demand.

Replace the fuel hose from the primer bulb to the onboard fuel water separator with a clear plastic hose of the same ID. Run the engine until it starts to bog down and have someone look for air bubbles in that clear hose.

If all that checks out, then test the LP fuel pump.

I test drove it today and had my son pump the primer bulb when it acted up and there was no change. Of course after 15 minutes the engine worked great and ran up to 5500 RPMs with no problem. So something somewhere along the line if plugging up the system or air is getting in there. When I get more time I'll start the fuel line check for air or a collapsed hose.

I replaced the RACOR and in-line filter about 4 months ago but I will check them better. I didn't see any water in the RACOR bowl but I didn't drain it.

Looks like Chawk man did it again and nailed it with the fuel line. The engine started acting like it was not getting enough fuel. The primer bulb felt soft and at one point was completely collapsed. I cropped off part of the old fuel line running to the engine and change the racor (which was only 4 months old but hey I'm trouble shooting). It started to perk up. Ran great but still not perfect. I think the old hose is sucking air somewhere else. I just have to get off my keister and swap out the old hose for a new one from the primer bulb to the engine.

I found the leak, it was a me problem. When I replaced the primer bulb in June I bought one that was too small, of course I didn't realize this at the time. But today I bought a 3/8" one and noticed when I removed the old one it was smaller, a 5/16. I made the swap and it ran great on an hour run.