Cleaning the Fuel Tank

[britinusa]

So it looks as though I need to clean out the fuel tank.

We have about 18gallons on board right now so I plan on burning that off over the next 10 days. Just replaced the 2mic Racor fuel filter and can see particulate in the bowl with fuel flow.

? - Does the fuel tank have baffles inside?

Paul

[KWKloeber]

 No need to be baffled about this, Paul.

It's one big box.

[Noah]

Paul- AGAIN I will say I'm not an engine guy, but something seems strange that you see "visible particulate" in your Racor bowl and how it got past your just changed 2 micron filter??

[Ron Hill]

Paul : Look at the old Mainsheet tech notes for an article I wrote on removing and cleaning a C34 fuel tank.

Yes, there is one baffle about in the middle of the tank.  There is a cutout on the bottom of the baffle so the fuel flow under it! 

You don't need to burn off the fuel.  You can pump it out by removing the output line (from pump to tank) and plug in another longer 3/8" line and run it to 5 gallon fuel tanks.  If your fuel system is plumbed correctly - Fuel tank to Filter to Pump - the fuel will get filtered so it's usable again.

A few thoughts 

[Ron Hill]

Noah : Check your fuel system fuel routing.  If your filter is before the pump you may what to change it to the other way around and have the pump receive filtered fuel. 

That way the pump can't get clogged up with junk!!   

Many posts on this very topic!!!

A thought

[Noah]

RON- mine IS set up properly in the correct sequence, I have no problems. I have a new Racor Series 500 turbine with a shut off valve. My system set up is not the problem. I was commenting on PAUL's comment/problem who said he had to clean his tank because he saw stuff in his bowl that got past his 2 Micron filter. That is what sounded confusing...his symptons not mine!

[Dave Spencer]

Hi Paul,
I cleaned my tank a few years ago per the "Ron Hill method". Pulling the fuel tank out was not a problem. To drain the fuel, I disconnected the fuel delivery hose and placed it in a 20 litre (5USG) yellow diesel fuel container.  I had three of them and it used them all half filling the last one.  The tank is definitely baffled and access into my tank through the fuel level sender flange was quite limited since the flange is so small.  I think I went through about 3 litres of acetone.  Likely overkill but the boat was relatively new to me at the time and it seemed prudent to overkill the cleaning since it involves some labour to pull the fuel tank out and I didn't want to do it twice. 

Sediment / particulate the you see in the bowl is likely in the water that has separated from the fuel - one of the main functions of the Racor fuel filter.  If you open the drain cock on the bowl of the fuel filter, the water should drain out into a suitable container and you should see clean and clear fuel left in the bowl.  Hopefully this is clear. (Both the fuel and my comments!    ). I have a few pictures that I'll look for and post them if you like.

[britinusa]

Thanks Guys.

IMHO - The fuel passes through the filter from bottom to top. And that's why the particulate is in the bowl and not in the fuel pump.

Just to repeat an earlier post

My fuel route is Tank -> Fuel Shut of Valve (on top of tank) -> Racor 2mic (R12S) filter -> Fuel Pump -> Engine mounted Fuel Filter -> Fuel Inector Pump


I had figured out the method of draining (and cleaning) the fuel from the tank by disconnecting the pump output and replacing it with a hose to the 5 Gallon Diesel Jug.

As the tank has a baffle (thanks for replying to that one too), I'll take the tank out (after draining it as above) and bring it home. Cleaning it is not something I want to try aboard the boat.

Paul

[KWKloeber]

No need to be baffled about this, Paul.

It's one big box.

Strange!  Mine has no baffle.  For sure, had it out.

k

[Noah]

Mine (1990) has a baffle as well.

In California, they have dockside fuel polishing services that come to you that some Forum folks have used. I believe Jon W. did? I recall someone else up in the Long Beach/LA harbor area has experience with this as well from a past post. Not sure of their cost or success in true cleaning the tank and fuel.

[lazybone]

No need to be baffled about this, Paul.

It's one big box.

Strange!  Mine has no baffle.  For sure, had it out.

k

Just a reminder. You have a different boat with probably a different tank.  I've' had mine out twice,  easy as long as there's only a few gallons in it.

[Dave Spencer]

Hi Paul,
You have likely figured this out already but here are some pictures of my fuel tank removal for cleaning from several years ago.  Different boats may have a different configuration but the job was surprisingly easy.  (something rarely said about boat projects! ) 
Four hoses; Fuel Fill, Fuel Vent, Fuel Pump Suction, Fuel Pump Return.  Two wires; Fuel Level Sender and Ground.  And several screws fore and aft of the tank.
Lazybone is right - it is easy to remove the tank and get it off the boat without spilling any fuel even if there are a few litres of diesel left sloshing around the bottom of the tank. 
I checked my records and I used 8 litres of Acetone, not 3 litres  as I said in my earlier post.  As I recall, I used half for a first cleaning and after shaking the tank around and dumping the acetone (it wasn't really all that dirty), I repeated the process with clean acetone.  Have a container ready to catch the used acetone.

[Jon W]

Wasn't me, I haven't had my fuel tank cleaned yet. I will be sometime this year. I am thinking of having access ports put in the top to clean the tank myself.

[Dave Spencer]

Access ports wold be very useful Jon.  I was tempted to put one in when I had my tank out to be cleaned but since it wasn't too dirty and the risk / reward analysis of cutting a hole in my perfectly good fuel tank didn't look to good, I passed.

[KWKloeber]

If I did that my thought was to locate it at the low spot (at rest) and on the plate install a dip tube, valve, and hose barb where I could suck accumulated H2O out of the low spot.