Mainship Pilot 34 Fuel Tank Pick-up - Screens ?

[TomF]

Dreaded water in the tank. I have a 2003 MP - 34 with a single 250 gallon tank and twin Yanmar 4lha-stp. I believe I have water in the tank as I have microbial growth (green slime). Are there screens in the pick-up tubes? My port engine gets bogged down and when I blow out the line she is good for a month or so. I am using Biobor JF fuel additives, are there any others to consider. My thinking is to run the tank nearly dry and then suction the remaining fuel from the port/stb fuel pick-up lines and then snake a line into the tank and pump out remaining fuel/water/slime that sits in the "V" in the center of the tank. If there are screens in the fuel pick-ups this will not work - thus the question.

Any suggestions or expierience with the remedy ?

[Keysdisease]

When the algae dies from treatment it becomes sediment and can clog whatever. What's happening with your fuel filters? Why only the Port engine?

Regardless given the age and conditions a fuel cleaning service is probably a good investment. I had this done on my olde MSI and the process was very thorough and not terribly expensive.

The crud is in there, its got to come out one way or another, get it out on your terms

[TomF]

Thanks for the reply. Agreed the crud and suspected water needs to go. I am up north and there are not many polishing contractors. My concern is that fuel polishing will not remove the suspected crud that lives in the pocket at the centerline of the tank. My 250 gallon tank has a flat bottom with a \_/ pocket located at the centerline of the tank over the keel. Will the fuel polishing be able to stir up that area and remove the crud ? This concern has me considering draining my tank and entering a suction line (pump) into both the port and stb fuel pick up locations to get the water and crud out.

[BruceK]

Without knowing your boat the pocket you describe has me thinking, what is its purpose, can you put in a drain valve after draining the tank? A "sump" with drain valve is a good way to remove crud.

[Keysdisease]

The service I used returned the fuel after polishing through a small flexible tube with a jet nozzle on the end. It swished around inside the tank like crazy making a hell of a racket and :stirring the pot" pretty well. If you can find one, these guys are typically pretty good about different configurations, and stirring up the sludge is part of the program. You not only have the usual crud, but all the dead algae as well.
He had a piece of clear hose on the intake and return, to keep track of how clean the fuel was coming out and going back

Good Luck

[TomF]

Thanks for the replies.

The "trough" in the tank is to allow sediment to collect. The fuel feed lines are located at the level plane above the \_/.

I assume in the 250 gallon single tank their are baffles that will prevent the neet "jet spray" that Keysdisease described.

Still thinking about how best to clean my tank, polish vs. drain.

Any experiences from MS owners with the single 250 gallon tank appreciated.

[rgano]

TomF, at first, I got the impression that you have a standpipe fuel delivery system through the top of the tank and then probably confused myself about that reading a later post. There is another thread running today where I passionately argue against standpipe systems. To me they are just a situation like your waiting to happen rather than continuous clearing out of any bottom debris. In another vein, there are kits available for installing inspection and cleaning ports into diesel tanks.

[Lollygag1]

I recently had my fuel polished. Cost was $1200 for both tanks. After doing this and changing the filters it resolved our issue with frequent clogged filters. Tech said that the port tank had growth and water thus causing the problem.

[TomF]

Lollygag1 - when you say "both tanks" do you actually have two seperate tanks , or is your MS Pilot 34 like mine with one 250 gallon tank that you can fuel from the port and starboard side inlets ? Did your tech polish in the water, or did they require you to haul your boat ? Glad to hear you got "cleaned up" . We are running to Block next week and may stop into RI for some cleaning ourselves.

[Lollygag1]

Tom we are a single engine w 2 tanks. The polishing took place in the water only took a few hours. The firm I had came to the marine and did this.

[Dougcole]

I just put a nylon tube into one of my pickups, and pulled a different one, including the standpipe out of the other tank. Neither had screens on them. I have an 05 400, so different boat but I would guess your tanks are built very similar to mine.

[TomF]

Doug, thank you. This answers one of my questions regarding screens. I am considering doing the same procedure that you completed. Can you tell me the GPM capacity of the pump you used. I have read that you need a minimum of a 80 GPM pump to stir up the microbe slime and water for proper filtering.

[Dougcole]

Originally Posted by TomF

Doug, thank you. This answers one of my questions regarding screens. I am considering doing the same procedure that you completed. Can you tell me the GPM capacity of the pump you used. I have read that you need a minimum of a 80 GPM pump to stir up the microbe slime and water for proper filtering.

Not sure on pump capacity but it is very high. I used micronix fuel service out of Stuart. His pump is on his truck. He pulled 55 gallons of fuel out of my tank in 10 minutes through a 3/8” tube.

[TomF]

I purchased a 16 GPM diesel transfer pump for $100 on Amazon. My buddy is going to lend me a high capacity racor filter set-up with a bunch of filters for change-out. I am going to self polish my fuel by using the port and starboard fuel pick-up tubes. I plan to polish the fuel in the next couple of weeks. I will report back on results once complete.

Thanks all for providing information and insight.