Fuel Filter Change on 2005 X-2/MCX

[rhsprostar]

Funny, I called Federal Mogul as well, about 2 months ago with the same questions.
Same answers as you got.
I am going to try to get the pump replacement "How To" together tonight.
Boofer do you mind if i use some of your pics for the initial part of the removal? They are better than what I have.

[boofer]

No problem.

Did you by any chance keep the old pump?

[rhsprostar]

It's in the Napa box! I am not sure how difficult these things are to disassemble as I think they are sealed at the factory but if yopu want to give it a shot PM me your info and I can send it to you.

[ncsone]

Can anyone (JimN?) explain the purpose of the short section (~4") of small diameter black hose that comes up from the top of the fuel filter outside of the pump assembly? It seems that if the fuel level dips below the top of that tube, the pump would be able to pull air into the pump. It also seems to me that it would be easier for the pump to pull air in than fuel. And, I think we all know that pumps are burning up because they are not getting enough fuel through them to cool.

Anyone have any thoughts on the purpose of that tube?

[JimN]

What the tube does depends on exactly where it attaches. My guess is that, since the regulator is on the top of the assembly, it's for what used to be handled by the return line.

['02xrider]

I to am curious about the small black tube. I just installed a new assembly and noticed the tube on the new one was capped off and attached to the side of the plastic. The cap does not appear to be temporary either. It is clamped to the tube.

On the old assembly, it was not capped..I am confused.

[ncsone]

The tube is a 4" piece of 1/8" plastic tubing that connects to a port on the top of the fuel filter. The tube runs vertically parallel the the entire fuel pump assembly. When the assembly is installed, the open, top portion of the tube sits about 5-6" off of the bottom of the tank. The bottom portion of the tube connects to the fuel filter and opens directly to the pump (filtered) side of the fuel filter.

Again, I am just not sure what the purpose of the tube could be other than to let unfiltered fuel into the pump when there is more than 6" of fuel in the tank.

['02xrider]

NCsone,

I would be inclined to think the same thing, but as I said, on the new assembly, the tube is capped off...

[ncsone]

I will have to look into that. Just ordered/installed a new filter and it did not come with a new tube/cap.

hmmm.

[boofer]

I think that the tube should be uncapped. I think ncsone is correct in his assessment. The tube may of been capped for shipping purposes. Otherwise, why have the tube if it is suppose to remain capped? I think that it is suppose to be uncapped.

['02xrider]

I am very curious about this now. As I said, it did not appear to be a temporary cap. It was crimped on..

[boofer]

My new filter did not come with a tube. So, I reused the one that was on my old filter. The only odd thing was the fact that there is a groove on the outside of the module for the tube. But, the nipple on the new filter was in a different place and would not line up with the groove. You can see this in one of my pictures.

I gander that the tube allows fuel from higher in the tank to be filtered since the nipple is on the outside of the filter. Since I did not remove the entire module to replace the filter, I did not get a good look at how the pump is oriented in the module. So, I do not have a clue why it is there if the pump module is only suppose to filter fuel from lower in the tank as mentioned by others.

[boofer]

Crimped on? Hmmmm. That sounds odd, unless it is meant as a cap during shipping and you are expected to replace it with the old tube. I might be tempted to give a dealer a call about that one. The guys at Charlotte MC are extremely helpful and might be able to give you the correct information. I believe that Joe is the tech or talk to Mike.

[boofer]

I did some looking at other boat/engine fuel delivery system configurations. Here is a page out of the PCM manual. These particular PCM engines are used on most of the other wakeboard/ski boats except Malibu.



"Fuel Control Cell (FCC) Fuel System
The Fuel Control Cell (FCC) eliminates vapor lock and air ingestion caused by fuel tank slosh, and provides the necessary filtration and water separation. The FCC system incorporates two (2) fuel pumps to provide an uninterrupted flow of fuel to your PCM marine engine. Fuel is fed into the FCC bowl by a low-pressure, high-volume electric fuel pump. This pump flows fuel at a volume much greater than the fuel flow rate required of the high-pressure pump and engine demands. The high pressure pump, mounted inside the FCC bowl, provides the necessary fuel pressure and volume to maintain proper engine performance. The FCC constantly has an ample supply of fuel to meet the idle, cruise and acceleration fuel requirements of the engine. The fuel pressure regulator may be located on the fuel rail or inside the FCC bowl, controls the fuel pressure and maintains a constant pressure across the fuel delivery system. Excess fuel, not used by the engine, returns to the FCC bowl. The fuel delivered to the engine by the FCC is filtered by a filter and water separator element, which surrounds the high pressure pump inside the FCC bowl. As indicated above, fuel enters the FCC bowl from two (2) locations, the low-pressure pump (initial input) and the fuel pressure regulator (unused, recirculating fuel). Fuel exits the FCC bowl at two (2) locations, the high-pressure output to the fuel injection system and all excess fuel in the FCC bowl is routed back to the tank via the return line."

Assuming the hose to the tank is mounted on the bottom, it is perfectly safe to assume that you can use most of of the fuel in the tank without any harm to the high pressure pump. I cannot say for sure but I think that if you were to run the tank/pump empty you can still run the chance of frying your pump. But, pop open the canister and replace the pump.

Just an example.

[boofer]

Thinking about doing the pump change with an aftermarket pump. How are the wires connected on the inside of the module? Same goes for the fuel lines inside the module. How are they connected? I do not want to get started unless I know that I have everything that I need.