2005 SR1800 Gas Filter Replacement

[Wallsy]

I purchased a gas filter for my engine at NAPA which was the only one they and other sources carried. Assuming that it was the right one, I disassembled the old one from my boat (no small project, incidentally). The old one looked awful, but beyond that it looked much the same as the new one until I tried to assemble the thing again. No way would it fit without forcing it. Then, I turned to my Mercruiser Service manual (26) which surprisingly to me turned out to be no help. In fact, they do picture my fuel pump complete with the bowl in place, but no mention of a filter or no picture of one. In fact, the note on the page says that the fuel pump cannot be serviced in any way and needs to be replaced if there is an issue. Given that I believe I had the current filter installed a few years ago. Does anyone have any idea what I'm dealing with here? I will say that the old filter was not only a dirty mess, but was somewhat caved in from what I now suspect was too much pressure on it when being tighted. It's possible that there is no replacement filter I suppose, and the last mechanic simply forced a new filter into the space, thus the caving or crushing of the old filter.

[mmwjr]

Is this a spin on fuel filter that looks like an oil filter? If so you need a Mercruiser/ Quicksilver fuel/ water separator filter. Or is this the cartridge filter in the carb?

[Wallsy]

Originally Posted by mmwjr

Is this a spin on fuel filter that looks like an oil filter? If so you need a Mercruiser/ Quicksilver fuel/ water separator filter. Or is this the cartridge filter in the carb?

Neither. It is the gas/water filter at the base of the fuel pump.

[mmwjr]

Originally Posted by Wallsy

Neither. It is the gas/water filter at the base of the fuel pump.

Since you said service manual #26 that would be the 3.0, correct? I haven’t seen a fuel pump with an integral fuel filter since the 60’s. What is the engine serial number? Can you post a picture?

[Wallsy]

Mine is 2005. S# OW334377
Here is a YouTube video describing exactly what I'm dealing with.

https://www.youtube.com/watch?v=x9x9S72qXlo

Thanks for your interest.

[mmwjr]

I went to mercruiserparts.com and looked up your engine serial number and got the following results for the filter.

Mercruiser part number 8M0048751

Quicksilver part number 8M0046752

Either of these should work, what part did you buy?

[Wallsy]

I used the Mercruiser #, but cross-referenced it to a NAPA part which doesn't fit. I'm going to a Mercury dealer this morning to see what they have. NAPA doesn't often mess up on cross-referencing so I'm not optimistic. This situation is all the more perplexing and frustrating because of the location of this filter under the pump which itself is near the bottom of the engine in a very confined spot. It's close to impossible to see what you're doing just getting the old part out to say nothing of what I anticipate the challenge to be putting a new part in once I find one.

Thanks again for helping.
Nelson

[shrew]

Try to avoid using marine parts cross-referenced with auto parts parts. I know, it's all GM. However, many times the equivalent part for automotive is not marinized (i.e. corrosion resistant, spark arrested, etc).

[jrsick]

Wallsy, I've never heard of anyone replacing that filter. May be done all the time but I haven't seen it. I recommend you install a fuel water separator kit in the fuel line between the tank and fuel pump. See Sierra 18-7982-1. Install the kit and you'll never need to open your fuel pump again.
I recommend you replace the fuel pump. If that bowl falls off or leaks you will have fire issue. Good luck and let us know if you need assistance.

[mmwjr]

Originally Posted by jrsick

Wallsy, I've never heard of anyone replacing that filter. May be done all the time but I haven't seen it. I recommend you install a fuel water separator kit in the fuel line between the tank and fuel pump. See Sierra 18-7982-1. Install the kit and you'll never need to open your fuel pump again.
I recommend you replace the fuel pump. If that bowl falls off or leaks you will have fire issue. Good luck and let us know if you need assistance.

Not sure if the 3.0 fuel pump is available without the integrated filter but I would not install the cartridge but use the inline spin on filter kit.

[Wallsy]

Mystery solved. NAPA had sold me the wrong size filter using the Mercruiser part number I had given them. I went to a different NAPA (only because I was close to it) and they swapped out the parts and I now have the right one. I learned that most owners of boats that have these filters in the base of their fuel pump never know that they have one and often never get changed. Until one day when ..... For what it's worth, the part I bought is from Sierra and the Sierra number is 18-7784. The one I removed was an absolute mess of gunk and junk. It's a wonder my boat ran at all.

[mmwjr]

Glad you got it resolved.