Fuel System; MC vs Malibu vs SAN vs .......

(boofer) · (boofer) **Join Date: Aug 2004** 07-09-2008, 12:28 PM

I own a 2005 X-2. It has become apparent that the fuel system that MC uses is good in theory but flawed. They use an in-tank fuel pump that uses fuel to cool the pump. The only problem is that if you get below 1/2-1/4 tank the pump can become overheated and fail. Yes, I said 1/4-1/2 tank (that's 1/4 to 1/2 tank of unusable gas). Not to mention, the replacement pump "module" (you cannot simply replace just the pump) costs $500+.

I want to know how other boats fuel systems work and if there are any known problems. MC is apparently happy to keep replacing these modules at $500 a pop. But $500 and 1/4 of a tank of dead gas on a daily basis is aggravating.

(canucked) · (canucked) **Join Date: Jun 2007** 07-09-2008, 12:47 PM

my nautique has a primary "low pressure" pump that feeds a "fuel control cell" which fills up with fuel and contains a high pressure pump. Both are in the engine bay for easy access. (i've replaced them both).

(flux) · (flux) **Join Date: Jun 2003** 07-09-2008, 1:18 PM

Hey, my Nautique has the same system as Trappers.

I just wish my fuel gauge worked.

(ralph) · (ralph) **Join Date: Apr 2002** 07-09-2008, 1:58 PM

The sanger uses the same system as the naut. I had a friend with a 05 X-2, same problem. Left him stranded a few times

(boss210) · (boss210) **Join Date: Jun 2006** 07-09-2008, 1:59 PM

My MB uses the same PCM fuel system as in the Natuque. The mercruser sustem has a pump that is housed in a box and your fresh water system plums into it for cooling the pump. For a while their was a upgrade that Merc was not charging customers for due to rapid failures.

(boofer) · (boofer) **Join Date: Aug 2004** 07-09-2008, 11:44 PM

Thanks for the information guys. Please keep it coming. If I understand correctly, there is a low pressure pump in the tank to get fuel to a high pressure pump that is located out of the tank. Is the high pressure pump electrical or mechanical?

Can you guys go below a 1/4 of a tank with no ill effects (other than running out of gas because you stayed out too long)? And, minus any gauge tolerances.

(lcky275) · (lcky275) **Join Date: Jul 2002** 07-10-2008, 5:40 AM

Your Mastercraft sounds alot like my Z71 Tahoe. $600 to replace my fuel pump because it burned up because of too little gas in the tank.

My 22V has a similar set up to the Nautique, with a low pressure and high pressure pump next to the engine.

(26lacefield) · (26lacefield) **Join Date: Aug 2006** 07-10-2008, 7:11 AM

MC put the fuel pump in the tank to help stop vapor lock. don't quote me on that but thats what the PCM guys were telling me. PCM figured out some fuel pump chamber thingy to stop vapor lock and put a patent on it. i don't know exactly how it works being i haven't had my hands on the PCM's yet but once the 09 Tiges get i will.

(xsmini) · (xsmini) **Join Date: Dec 2005** 07-10-2008, 8:05 AM

Malibu has an in tank pump that can be run dry. If it fails, it has a backup built right in there. I haven't seen one failure yet since the change was implemented

(boss210) · (boss210) **Join Date: Jun 2006** 07-10-2008, 9:21 AM

The PCM pump sits in a billet housing, inside the housing is the fuel filter and the pump, it stays submerged in fuel keeping it lubircated and cool. Their is a smaller pump under this cyl that is the transfer pump (Electric), puts out only about 6 psi just to help in the fuel delivery.

Kind of a pain to find the waterseperator filter, (not many PCM dealers out their) but a nice system.

(boofer) · (boofer) **Join Date: Aug 2004** 07-10-2008, 5:27 PM

I really appreciate the help. This information is very helpful in understanding the different fuel systems. I went by the PCM web site and the manual was very descriptive.

I could not find any good information on the Malibu fuel systems. So, any help there would be greatly appreciated.

Does the fuel line from the tank just simply attach at the bottom of the tank on these setups with the FCC (Fuel Control Cell)?

(Message edited by boofer on July 10, 2008)

(malibudude) · (malibudude) **Join Date: Feb 2001** 07-11-2008, 8:16 AM

The electronic fuel pump on Malibus is located on the port side rear of the engine block.

(boofer) · (boofer) **Join Date: Aug 2004** 07-11-2008, 9:13 AM

Thanks a bunch guys.

(mvl) · (mvl) **Join Date: May 2004** 07-11-2008, 11:01 AM

I've run my MC's dry numerous times, been towed in. I run it most of the time with 1/2 or less. Never heard of anything like this before. Not saying it can't happen, because obviously you had it happen, but like I said....I've run it till it quits many many times. Almost never have 3/4-full.

(boofer) · (boofer) **Join Date: Aug 2004** 07-11-2008, 2:45 PM

Mark, run by the Team Mastercraft site and search for fuel pump or fuel filter. Apparently this problem is overly common.

Basically, the pump (filter attached to the bottom of the pump) is in the tank. The filter is only filtering the last half of the tank. Once the tank gets down below 1/4, the pump is not being cooled by the fuel. This leads to the failure of the pump. It is a Mastercraft design and not an Indmar design. The replacement pump module (you cannot just buy the pump) is over $500. That does not include labor.

From what I can find, this fuel delivery system has been used since around 2000.