LONG post, I apologize in advance but I wanted to be thorough.
So, I have been experiencing some poor engine performance which I suspected was fuel related in my '08 Wakesetter. I picked the boat up around 6 months ago and I have spent the entire winter tuning, replacing, and improving almost everything. I haven't gotten into the fuel system until now, I've been going out more since the weather has warmed. Most of the issues are at idle and low speed, it just didn't seem to be running real well although would run decent at WOT.
After doing the homework, I learned that Malibu made a change mid 2008 in fuel pumps going from the Gen2 to a Gen3 in tank pump. The main difference between the two boiled down to an integration of the fuel pressure regulator into the delivery port, thus making the Gen 3 "maintenance" free. The pumps both are spec'd to deliver 60psi constant pressure, so after a trip to my local Auto Zone to borrow a pressure test gauge, I figured out my old Gen2 pump just wasn't getting the job done. Arguably it could have been just a bad pressure regulator, which are still available for the old Gen2 pump, and it could have been the filter socks or a combination of all the above. However, given summer is around the corner, I just decided to bite the bullet and replace the complete pump. Given the boat is 12, the original pump definitely did it's job for many, many years.
Changing the pump was decently easy, it takes much longer to remove access panels than it does to swap them out. First step is to remove the U bend panel, which is a handful of screws and 4 joiner plates. Once those are out, the U bend comes right out. Next, remove the floorboard/tank cover by removing two screws towards the front of the panel. You should now have complete access to the pump. If you find 12 years of nasty, you might take a minute to clean that up.
Next step is to relieve any pressure remaining in the fuel system. To do this, unfortunately you'll need to remove the intake plenum to access the relief valve. Had I known prior exactly where the valve was located, I might could have used a long screwdriver to depress the stem without removing the plenum. However, I had no idea how much pressure and or fuel was going to escape, so off it came. If your tackling this project you more than likely know how to remove the plenum (6 allen bolts), so I'm not going to elaborate. Long story short, there was the smallest amount of pressure behind the valve and it barely expelled any fuel.
Once that's complete, remove the electrical connection on the old pump by lifting the lock tab and pulling it out, move to the side. Next, you'll need to remove the stainless hose clamp on the fuel line. These clamps can be hell to release, and while not the safest method I ended up using a Dremel and very gingerly cut the band enough that I could pop it loose with some needle nose pliers. Next is releasing the line itself, which you will need a fuel line release tool. Luckily, I've had one for years but their available at any auto parts store. Use the 7/16 tool to depress the tabs and release the line. There will be fuel in the line, so keep it elevated and move to the side.
Next, remove all the 3/16 allen bolts holding in the old pump. The pump is actually mounted on two springs, so the old pump will quickly pop up from the tank once all bolts are out. Carefully remove the pump and hopefully you thought ahead to burn down the tank to almost empty. I opted to replace the tank gasket, you may or may not depending on how old yours is. I was actually surprised how nice the old gasket looked, guessing the PO must have changed it at some point. Carefully put the new pump in, and basically reverse every step until your back in business.
NOTE: I did have one issue with the electrical connection on the new pump. There is a small ground spade on the top of the Gen3 fuel pressure port which is NOT on the older Gen2. After doing some research, I learned that the electrical connection on newer boats came with a 5th wire separate from the actual plug which attaches to the ground spade. I had to splice into one of the two ground wires on the plug harness and run a separate wire to the spade. No big deal, but if you don't have wire and spades handy you'll have to go to the store.
End result is a complete success. Truly night and day difference in the way the boat runs, it was quickly obvious that the old pump was not delivering 60psi at any point.