Draining the Fuel Tank

[manuevers]

My Yanmar 3GM30F just stopped running. The repairman said it was water in the fuel and the injector pump and injectors needs to be rebuilt. He is taking care of that but he said I should drain the fuel tank and add a fuel separator. I am looking for recommendations on both the type of fuel separator to purchase and well as the procedure for draining the tank. I'm guessing to drain the tank I should buy some type of pump from West Marine, pump out all I can, remove the tank, then visually inspect it to make sure there is no water or gunk left in the tank.

Thanks for any advice.

 

[Steve Dion]

A Racor R120 will do the job. You can find them for about $70-75 on eBay.

As far as the fuel in the tank, you can just pump it out into some cans. The fire department will usually take the old fuel off your hands, or you can get a Baja Filter and clean it yourself.

 

[Hunter voyager]

I also had to fit a new lift pump and clear the tank to my 34 but the injector pump was fine,

Fit a primary fuel filter if there isn't one already. Mine had a racnor but don't know if original.

I used a hand pump to empty the tank (the same one as used for pumping out the engine oil out through the dipstick pipe.)

I then fitted a 4 inch diameter bekson inspection hatch to the top of the tank which enabled me to wipe out the tank by hand.

There is no drain connection in the tank and water will always condense in a tank. I have shortened the lift tube and removed the gauze filter from the bottom of the lift tube. ( If I get some dirty deisel I want the debris to get to the racor filter and not just block the pipe in the tank.)

Clearing this in mid Atllantic was not amusing!

Adding water absorbsion additive to the fuel is also a great preventative measure IMHO.

 

[Rick Sylvester]

I HIGHLY recommend the 500 series Racor.

The see-through bowl will collect water where you can see it. The petcock allows you to remove it easily should it happen again.

The much larger filter element is not only cheaper, it will swallow a great deal more dirt before packing up. Diesels draw a relatively small amount of flow so don't size the filter based on flow rates. Many people miss the much more important issues when focusing on this.

Further, with the optional vacuum gauge you can keep track of how dirty the element is (more vacuum means the element is more plugged) before the engines quits. We all know this will happen at the worst possible moment. Now that they have a drag pointer you can even check the highest vacuum value after the engine is shut down and cooled off. This allows you to be proactive.

I consider this to be one of those "don't leave home without it" things.

Good luck.

 

[Dan Johnson]

Rick...

nice installation, with everything easily accessible in a crowded compartment!

 

[Alan]

Just out of curiosity, how did he determine that the injection pump and injectors need a rebuild?

 

[Jim Haynie]

I had same problem a few years ago. Did similar to Rick Sylvester with addition that I left old small filter canister in place and added some extra tubing and valves to put the two filters in parallel. Now I can simply turn a few valves to switch from teh new (big) filter to the old one and then do the cleaning/replacing when it is more convenient. Also added a squeeze pumping bulb (from outboard motor fuel tank) ahead of the flter network. This is FAR better for filling the newly replaced filters and bleeding system than anything you can do with the lift pump lever. I did this 3 years ago and have had no problem with it. To bleed system now I don't start at the beginning and go through every crack and fitting as recommended in repair manuals. I simply crack the last fitting going into the high pressure pump and keep squeezing the bulb until no more air or bubbles. A lot less trouble and time than before. I was afraid that the material of the bulb would not be compatible with the diesel fuel as it was designed for gasoline, so I bought a spare just in case it was needed in a hurry--it's still in the package.

 

[serenisea]

When I had to replace the holding tank in our former Hunter 28, I had to cut through the aft bulkhead, drain the fuel tank and take it out in order to access the holding tank.

I used the Tempo Oil Boy to siphon out the fuel contents, and emptied several reservoirs of the diesel fuel into 5 gallon fuel jugs. It worked great. When I was done, I put the fuel back into the tank (although you would probably want to replace what you remove). The Oil Boy worked great. I also used it to re-prime the line to the fuel filter by putting the tube in the end of the supply tube from the tank at the filter. Didn't have to do any bleeding.

NEVER TRY THIS WITH GASOLINE!!!!!!

Gary
s/v Serenisea2

 

[mark_swart]

My 3GM30F also sucked water when the plastic deck fill cracked and started funneling in water. The diesel didn't even smell like diesel it was so diluted. HOWEVER, once we pumped out the tank, cleaned it and bled the fuel system, she started right up and has been running strong as a horse every since (that was June and we use the boat almost every weekend.) I was also fortunate that someone had already added an access plate and the tank on the H34 isn't too bad to get to once you squeeze into the lazarette.
I"d be leery about rebuilding anything, why not clean the tank and fuel system, drain the lines, put in a new filter and give it a try?

 

[mark_swart]

My 3GM30F also sucked water when the plastic deck fill cracked and started funneling in water. The diesel didn't even smell like diesel it was so diluted. HOWEVER, once we pumped out the tank, cleaned it and bled the fuel system, she started right up and has been running strong as a horse every since (that was June and we use the boat almost every weekend.) I was also fortunate that someone had already added an access plate and the tank on the H34 isn't too bad to get to once you squeeze into the lazarette.
I"d be leery about rebuilding anything, why not clean the tank and fuel system, drain the lines, put in a new filter and give it a try?