Fuel Tank: Clogged?

[Celestialsailor]

Originally Posted by agilmore

The fuel line was not clogged.

There is a one way valve, and it was functional.

I used Stabil (diesel) and Biobor JF during the winter, but nothing since the warm weather set in.

Yesterday I pulled the batteries so I could get to the fuel tank. First I took a sample from the bottom using a long tube and a hand pump: no water or bugs, but a fine black (dark brown?) silt. It's not magnetic, but it is gritty. BTW, I think the tank is aluminum instead of galvanized steel as I first thought. I'll take a magnet with me the next trip to the boat.

I pulled the pickup tube and found the screen at the end was covered with a mixture of the black grit and slime. I pulled the screen out, and as you suggested, I am going to leave it out!

So, now I need to find a primary filter (the engine has a secondary filter). The engine manual suggested the RACOR Model 500 MA, but I think I will look at the 500 MAM with the metal bowl. It will be a tight fit because there is not much room in the engine compartment.

Any suggestions on a smaller diesel filter? The usage rate is .46 gal per hour (I know the flow rate is higher, but the manual does not spec it). Anyone know the typical ratio of flow rate to use rate?

Also, concerning polishing, since the fuel injector returns some fuel to the tank that has gone through the primary and secondary filters, it seems that the fuel will be polished when running the engine. So why should I install a polishing system? I suppose I missed something rather obvious, so feel free to 'set me straight' :-)

Thanks to each of you for the inputs,

Alan

The reason I asked about if the draw tube material was to ascertain if it was copper. I used a biocide one time and it reacted with the copper, producing a black crystalline material. The black slim is usually dead algae.

[John A]

IMHO One of the most important safety devices on the boat is the engine! A review of boats lost due to engine failure has been reported on this forum numerous times. If you have "silt" in your tank that "silt" is going to travel up into the primary filter during the agitation of the fuel during a chop, swell, leaning the boat over, etc, and stop the flow of fuel!
the engine will only fail when its running and you're only going to have the engine running when you really, really would like to be able to use it. Deal with dirty fuel at your marina or deal with it on a lee shore. Your choice.

I steam cleaned my tanks before cruising, I Jerry canned ALL of my fuel and poured it thru a Baha filter and still I had to swap-out the Racor filter while underway.

I can also change the secondary filter and bleed a 4-108 in a ten foot swell, singlehanded, but that's another story. So to is entering a crowded anchorage and anchoring under sail alone, singlehanded of course.

[roverhi]

I'd stick with the transparent bowl for the Racor. Really nice to be able to look at the filter and see if there is any junk in it. A sudden jump in water at the bottom or level of crap lets you know it's time to change the filter and/or do something about the fuel in the tank. It's been very reassuring to look at the filter and see nothing collecting at the bottom. The filter had plugged after the TransPac and addition of biocide had riled up the crud in the tank and nearly blocking the filter. Hadn't been religious about looking at it and the change from clear to translucent slipped by me. The metal bowl is required for commercial boats, only.

[Celestialsailor]

All the above...I have a Racor 500 see thru. I also have an electric fuel pump which auto-bleeds my Westerbeke W46. It also aids in starting.

[undercutter]

Originally Posted by Sailmonkey

Ok, I found the valve that is being discussed. I don't see any reason for this to be on a diesel powered boat........although it may have been added for some strange reason.

These valves are placed in the fuel system to prevent loss of prime. Usually when the head height is at the limit of the lift pumps capacity to prevent fuel from draining out of the lift pump back into the tank.

We have a couple of machines where the fuel tank is more than 4' below the engine and without this valve you would have to prime the engine every time you wanted to start it. If the tank is not much lower than the engine then probably do not need this. More common with 2 stroke diesels like "detroits".

[Hudson Force]

Originally Posted by undercutter

These valves are placed in the fuel system to prevent loss of prime............................ We have a couple of machines where the fuel tank is more than 4' below the engine and without this valve you would have to prime the engine every time you wanted to start it.............................

I totally agree. I did remove the check-valve from one of my tanks because it was defective and sticking; howerver, my tanks are both level with my engine. There are configuarations when they are needed.

[agilmore]

Celestialsailor, the draw tube is plastic. It was covered with a thin layer of black 'stuff' that wiped off with a paper towel. The cork float also had a thin layer of black stuff on it.

John A, single handing is the best way to go. I am working towards that. It will take a while, but for safety reasons it is reassuring to know that if my crew (of one, my son) is injured, sick, or otherwise, I can handle the boat myself. I just installed lazy jacks, and little by little each piece of the puzzle is being changed from a two person operation to a one person operation.

Roverhi, 'metal bowls required for commercial use only' . . . thank you for that tidbit.

Alan

[rigormortis]

Does no one use a vacuum gauge downstream (engine side of Racor) to monitor gradual clogging of filter? Seems like a good idea and gives indication of clogging beginning as the suction increases, visible on the gauge. Racor makes them. Here is mine. Visible from the helm, with a sharp eye.
Pete

[ranger58sb]

Thanks, Aloha, I appreciate the insight!

-Chris