Sunday, April 9, 2017

Time to talk Dirty - Fuel that is

Cleaning the Fuel Tank

Recently we were motoring and the engine failed, no big deal, we just coasted to the side of the river, tied up and I went and checked the fuel system. The Fuel Filter/ Water Separator was full of crud. 10 minutes later it was cleaned out and engine started - on our way. Need to clean the fuel tank!

Emptying the Diesel Tank

The tank was just over 50% full according to our fuel gauge, that's about 12 Gallons, the tank holds 23 according to the label on the top of the tank. So we had to drain that fuel out.
Our fuel system is setup like this:




Tank - 2 Micron Fuel Filter Water Separator - Fuel Pump (with built in filter) - Engine Filter - Engine Injector Pump - Return Fuel Line - Tank


To drain the tank I disconnected the fuel hose from the output of the fuel pump and replaced it with about a 4' long spare piece of fuel hose. Stuck the end into a 5 Gallon Diesel Can and turned on the Engine Ignition. It took about 10 minutes to fill the Can.

I had two 5 Gallon jugs with me.
Later today I'll go back to the boat and drain the remaining Diesel into a 3rd Jug.

The white cloth under the tanks is actually a Puppy Training Pad. They make great work place protection sheets and are much cheaper than anything Marine.



Getting the Tank Out

The tank is located Port side aft, it's basically at the foot of the Aft Berth. So I have to empty the aft berth (cushions, as well as all the other stuff we keep in the Garage) and then remove the Wooden Panel to covers the Fuel Tank Area.

It's only held in with about a dozen screws, my DeWalt gyroscopic screw driver makes quick work of those.




That small hole in the underside of the deck above the tank is an inspection port that can is located inside the Port Aft Cockpit Locker. Pretty much useless and to get to it the locker has to be emptied, and then get myself into the locker. It's a game!

The Red covered bundle of wires is the Engine Control Harness that I replaced last year. I did a nice job on that. 

Here's hoping the fuel tank is OK, there are no signs of any leaks. It's held in by just a few screws on Tabs at each end that secure it to the shelf on which is sits.

There are 4 hoses connected to the tank: Fill Hose, Overflow Hose, Supply Hose, and Return Hose. On the top is the Fuel Sensor but that's just a couple of wires. However that sensor will get removed in order to clean the tank.

 After disconnecting the Fuel Fill hose (hose is breaking down, need to replace, so I cut that one off.), Then the Fuel Vent/Overflow (but it's illegal to let fuel overflow) and the Aft earthing straps.

Moving on to the front end of the tank.
It's cramped down here. Peggy took these pics, I'll not show those that show my wrong side! 😄


 Disconnect the Fuel Delivery hose (put end in a bottle to capture the few remaining drips in the line that goes to the Fuel Filter.) I could not get the hose off of the barbs on the end of the Fuel Shut Off valve, so I used a wrench to disconnect the barb fitting from the valve. Need fuel teflon tape to put it back.

Disconnect the Fuel Return Hose, easy.

Disconnect the Fuel Sensor - there's no plug in the line so I had to cut them. Will need to put new butt joint to reconnect them.

Unscrew the 6 screws holding the front end of the tank down to the plywood base. Discard the old unused earth strap, I had put in a new strap to the earthing block in the engine bay during the harness upgrade.
 Cleaned up the work area and eased the aft end of the tank up over the wiring and down towards the aft berth flooring.

There's definitely more fuel than I thought left in the tank. It weighs more than the 15lb advised by the C34.org forum guys.

Rubber pads on the floor to prevent scratching.
Tank is Out! Phew!
 Moved over the Stbd side of the aft berth to figure out how to get it out of the cabin.

The max width of the tank (along the edge nearest in view) is 24", the Cabin entrance is only 19" wide. The tank is 12" tall. so need to turn the tank on it's side - Fuel Return adaptor has to be down rather than have the Fuel Fill pipe, Fuel Shut off and Fuel overflow pipes down. The tank has at least a couple of gallons of fuel left in it (Yep, I forgot to take an extra fuel jug with me to decant the rest of the fuel. I figured there was less than a gallon in the tank, Wrong!)
Tank turned on it's side so that Fuel Fill pipe on the far end of the tank is now near the top right and the tank will come out of the cabin doorway.
 Awkward, but doable. Being careful not to scratch the cabin door or frame.

Once the tank was out near to the Galley Sink Cabinet, I was able to lift it above the sinks. There's only a few inches of room to spare between the back of the sink area and the cabin door frame, but not a big deal.


Grunting a bit, but the tank is coming out of the cabin.

 Happy dance. Tank out, nothing broken.
 Getting the tank ashore.

 As well as taking these pics, Peggy had the truck ready to load the tank.
Ready to strap the tank down and head up to Ohio (Kidding! the Forum guys will get this one)

The whole process from arrival at the boat, unload the Aft berth (cushions, etc.) Removing the port side panel, extracting the tank, loading onto the truck - About 1 hour. Less than 2 from house and back.

 I suspended the tank in order to drain the remaining fuel out of the Fuel Fill pipe.

Supporting it like this facilitated tipping the tank on end.


 Before removing the Fuel Sensor, I marked it's orientation with a piece of blue tape. I installed that sensor over a year ago, and still recall what a pain it was to orient the plate holes with the tank when the tank is in place.
 It's official. This is the original tank, 23Gallon capacity and for diesel fuel only.

I drained over 4 gallons of fuel out of the tank, that's about 32lb with 15lb tank weight - 57lbs explains why it felt heavier than expected.


Plan was to wash out the tank using Simple Green. I used a whole gallon, undiluted.

Poured in about a quart, swished the tank on it's suspension rigging and drained it out into a bucket. Repeated until all the SG was used up.
Grit and what!
The particles out of the tank measured upto 1/2" not much slime.

I poured the bucket contents through a filter but quickly clogged up. So that shown here is left after pouring the bucket's contents into another container.

Finally I put all of the fluid and grot into the original Simple Green bottle and set it on an angle overnight hoping that I could see the settlement in the morning.


That settlement is pretty much the same look as that in the Racor Filter base.

All of the fuel that I recovered from the tank after removal will be treated as compromised and discarded at the local recycle station.
The fuel pumped out of the tank passed through a 2 micron filter, so there's no particulate and it can be reused. I'll put some bioside in each of the four 5gal jugs before putting it back on the boat.

I'll check the Fuel overflow / vent to make sure it has a critter guard in place just in case all that grit is from something crawling into the tank.
And, of course, I'll replace the Fuel Fill hose and Fuel Filler cap, changing that from Sun damaged plastic to Stainless Steel. I'll also run a bonding strip from the new cap to the Engine -ve bus bar.

Putting the tank back in place should be easy (certainly lighter) and I'll rerun some of the wiring so that it does not wrap around the hoses.

Big thanks to the c34.org forum guys that provided lots of advice on what to expect in doing this job.

Glad I didn't have to drive up to Ohio

See you on the water.

Paul