Fuel issues

[Smoken]

We purchased a 2000 53’ Voyager in December of last year. The boat had sat for 2 years so we knew that there would be multiple projects.

We cannot seem to fix fuel issues created by the lack of use. We have fungus in our tanks and have tried many things to try and fix including fuel polishing , bio cide fuel additive, over 550 gallons of new diesel and we change the racor filters every eight hours.

Is there anyone who can give us guidance on what we need to do next?

[km1125]

What did you do to "fuel polish"?? How low have you run the tanks? How many tanks do you have and do you have the problem on all the tanks?

The best way to clean the tanks is having a high-volume high-pressure pump with a couple filters ahead of it. You need access to the top of the tank to remove something like a fuel sensor so you can stick two copper tubes in there... one to the bottom of the tank and the other than you can move around. In-tank baffles can make this harder to do. The flow comes from the one you stick down to the bottom, and the other one you move around as much as you can to stir up whatever is remaining in the tank. Also helps to pinch off the end of that one so that the returning fuel is spraying out (like a hose sprayer). The less fuel in the tank the higher the ratio is in junk/fuel. If your tanks are low enough, you can pump everything out of one tank into another so once you get the tank clean you fill it only with clean fuel.

The other thing you can do is make modifications to your fuel filtering process to make it easier to switch to a backup so once a filter is clogged, it's an easy process and doesn't delay your boating. You put in a dual two-way valve and wire before and after two filters so it's an easy toggle to the backup filter. You can also put in a meter to measure suction in the line so you can see when the filter is getting clogged before it affects engine performance.

[Smoken]

Thank you so much for this information. We have two 400 gallon tanks. When we had the fuel polished that is the process they used but I think we had too much fuel in the tanks. We will check into dual filters, that sounds like a great idea. Thanks again. We appreciate your help.

[RobGunn]

Iv had issue with one of my diesel tractors on the farm. I was final able to get the issue resolved by draining the tank, rinsed out with alcohol, replaced the strainer on the end of the pickup tube, added a cheap see through automotive inline filter before my good filter (this can be changed very easily as needed). I continue to add bio additive to the new fuel. So far in 2 years Iv had no issue other than change the cheap filters once one or twice.

[Hugo]

One school of thought is to no worry about it and just use multi stage filtration. A big quick spin on 30 micron bulk filter easy to change then a 10 micron racor and 2 micron on engine. You'll just need to add the 30 micron infront of your racor. You racor won't get gunk in it anymore with spin on filter in front of it. You'll just be changing the big 30 micron spin on as needed until problem goes away. Put a vacuum gauge on it so you can monitor restriction.

https://www.sbmar.com/articles/marine-f ... board-way/