Water & Fuel; Fuel & Water

But thankfully not together.

My next to last set of friends/crew left Friday for Tallinn, and I’m waiting in Helsinki for last set, my dear friends of 30 years, Leonie and Martin.  This weekend alone has given me the time to pretty much do nothing and on a boat nothing is always fun!

I’m writing this piece now, Monday morning, on the forlorn hope, that at some time in the next days, I will actually have Wi-Fi that is connected to something.  Virtually everyone says they have Wi-Fi, which really only guarantees you a router is you read the fine print.

I’m also doing a load of laundry having got the Splendid to work for the first time this year.  A few weeks ago, I was inspired enough to actually take the back off to see what the problem was, hoping it was something obvious and that I could fix.  An unplugged plug being my first choice.

Well, it did turn out to be obvious, but a little harder to remedy.  The belt had simply come off the motor and wheel for the drum.  I made a halfhearted attempt to get it back on, and then inadsplixity, I decided it was easier to collect all the screws for the back, put them in a baggie, tape the baggie to the back and then put the back panel in the compartment under the unit.

What was I waiting for? Godot?

In any case, in the time it took me to do all that, it took me less time to get the belt back on yesterday.

My only disappointment in the whole deal was that I discovered that it will still not run off the inverter, but only with the generator.  I seldom run the genny, but am now, as I must to a wash for the bed linens for my next guests.

Now back to our story: water and then fuel.

Yesterday, remember the day with nothing to do, I had washed my face in the sink in my head and as I always do I listen for the telltale sound the fresh water pump makes as it cycles off.  This usually happens a few seconds after the water is turned off.

I was listening intently because I knew the port side water tank was almost empty and I try not to let the pump such a lot of air.  Because when it does that, the faucets will spit at you and as they are at the level of one’s crouch.  Then a few hours later, when you innocently go to turn on the cold water, your crouch gets blasted by a plug of cold water.  If you’re dressed it’s downright embarrassing, but if naked, it just plain shocking.

So, listening closely as the pump droned on, I went to switch the water tank valves.  Turned off port, turned on starboard.

Now usually at this point, it may take many seconds or even a minute or two, for the pump to build sufficient pressure and turn off.

Sometime by turning on the kitchen tap, I can facilitate this process to get the air out, since the kitchen is the highest tap.

I do so and the water pressure is not very strong, much like it is running out. Strange I think.  I turn it off and the water pump continues to run and run.

Well, just a few months ago, the same thing had happened.  I spent an hour trying to diagnose the problem.  Then, it turned out the valve for the just emptied tank was NOT fully closed, maybe open only 1/8” but that was enough.

So this time, I think oh, I know this problem, I go check the valves, but the port tank was fully closed.

Being at a marina, I had turned off the Maretron system which tells me the level of the tanks.  I wanted to do this because my first thought was the tank I thought was full, was actually empty.  This had also happened to me somewhere in the past.

The Maretron sensors confirmed that I had one full tank, but it also said that I still had 20 gallons in the port tank, which I had thought was empty.  The Maretron tank sensor works well for low quantity, so now I was getting flummoxed.

I had already turned off the water pump just so it would keep running while I tried to find the problem.

I switched the tanks again, back to the not quite empty port tank; turned on the pump and ran the kitchen water again. No change, I tried the hot water, but there was not hot water!

Now, this was getting stranger still.  Even if the water tanks are empty, the hot water tank is always full since if the water pump cannot pump water from the tanks, it also cannot pump water out of the hot water tank.

Would you like to guess what the problem was?

 

So twenty minutes later, I finally decide to check all the faucets in the boat.

Sure enough, the faucet in my head was happily running just as I had left it 20 minutes earlier! I turned it off the water pump turned off within seconds.

Now, a little fuel issue, but at least I understood what happened immediately.  But I will give you time to guess for yourselves.

Coming back to Helsinki, we had motored for about 5 hours. No problems.

The next morning, I go to the engine room to check the fuel tank levels.  I do this my means of sight tubes. Sight tubes are connected to the top and bottom of each tank and indicate the level of the fuel inside the tank just based on the fact that fluid finds its own level.  The only thing you much check is that for the sight tubes to be accurate, the valves that connect them to the tank must be open, top and bottom, as well as the feed and return valves to that respective tank. Four valves all must be open.

I check the starboard tank that the motor had been feeding from, it indicated 3” of fuel, at this point about 35 gallons (yes, I need fuel).

The port tank was empty, empty.

I knew I was low on fuel, so I had used the fuel polisher to transfer all the fuel for port to starboard, just in case.  I did not want the engine to run out while underway.  I know the tank is empty when the fuel polisher is just sucking air.

I also checked the port tank, even though empty, sometimes the return valve is hard to fully close, so it can collect fuel sometimes.

I go to open the four valves and what do I see, they are already open!

Now that strange.  Stranger still is that the engine ran and had no problem running.  I had done this before last year.  I had both feed pipes on from each tank, but one tank was empty.  It took me an hour to figure out why the engine would not keep running.  Why? Because the fuel pump is sucking air from the empty tank and pumps always prefer air over liquid as it’s easier to suck.

So why did the engine have no problem running?

 

 

And the answer is, last year when the engine would not start, the feed pipe was open, but the sight tubes were closed.  Had the engine had fuel this is the normal running configuration.  By having the sight tubes closed normally, there is less chance of air getting into the system.

This time the 4 valves were open on the empty port tank, the 4 valves were also open on the tank the engine was supposed to be feeding from.  But again the engine ran for 5 hours with no hiccups at all, like the good Ford Lehman it is.

Why did it work?

The running engine returns to the tank much more fuel than it needs.  Because I had left the sight tubes open also, the engine never got a chance to suck air from the empty tank.  Instead after start up, as it returns fuel to both tanks, the fuel to the empty port tank is flowing right back down the sight tube and being feed back to the engine.  And it was just enough (since some was returning to the starboard tank also) so that the fuel lines never got any air ingested.

Had I gone down to the engine room while the engine was running, I would have seen a full sight tube.

The reason the previous time something similar happened, and the engine would not run, was because the sight tubes were closed.  Now the fuel being returned has to go into the tank, fall to the bottom of the tank, splash, and collect back at the lowest point near the feed pipe.

But that takes too much time and even the splashing fuel in an empty tank causes a lot of air.

SO this time, having the sight tubes open, kept the fuel for aerating itself and also minimized the time it took for it to be at the feed pipe.

All’s Well that Ends Well.

Now, let’s go find some f…ing internet.

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