Bad Judgement, Bad Experience

[dvd]

Someone once said that good judgement comes from experience, and experience comes from bad judgement. Well, I'll have better judgment after yesterday's experience.

After a few days of wonderful cruising on Chesapeake Bay, with water so flat it would have been great for water skiing, the wind picked up while we were at anchor Friday night 15-20 knots with sustained gusts up to 30. No problem in a protected cove, but took off Saturday AM to cross the bay back to home port 2 hrs. away on the Eastern Shore. The Northwest winds kicked up 2-3 ft waves at frequent intervals - handled OK, but a bit uncomfortable. I had run my fuel level down pretty low, thinking I would have my tanks cleaned soon, so was carrying only about 30 gallons (normal fuel burn is 2 gal/hr.). About 1 1/2 hrs into the crossing the engine died. Dropped anchor, went down in the rolling, hot bilge and changed the primary fuel filter (which didn't really look too bad), bled the system and it started back up. Ran for about 15 minutes and it died again. Dropped anchor and looked at the new filter and it looked pristine. Re-bled the system at the secondary filter, but it wouldn't start. Re-bled the system at the injector but still wouldn't start. Finally called for a tow to get back home (about three miles).

So, even though I saw fuel drip out as I bled the system (under less than ideal conditions!) I am assuming that somehow I got an air lock -- perhaps from the pick-up in the tank pulling in air as the low fuel level sloshed around in the heavy seas.

Tucked the boat into its slip and came home - will be going back down in a couple of days to figure it all out. Any other ideas?

Thanks,
dvd

 

[Tom.B]

If I was to guess. The rolling seas and low fuel exposed the fuel pickup to allow the engine to take a gulp or two of air. I have talked to more than one boat owners that have had this issue in rough seas. Both sailors though. I doubt it's anything serious.

 

[El Sea]

Pickup tubes do not go to the absolute bottom of the tank and fuel gauges are anything but accurate. I think you ran out of fuel.

 

[ARoss]

I agree with the "low fuel" diagnosis. Been there, done that. Lesson learned. Hopefully.

 

[Edelweiss]

Yikes!!! 30 gal.?? When I get down to 1/4 tanks, about 125 gal. total, I'm shaking in my boots and looking for a marina.

In a boat or plane it's really just too dangerous to cruise while low on fuel. The walk to a gas station is full of pitfalls.

 

[knotheadcharters]

My experiance was somewhat different, the first few times I had my boat out I was unsure of my fuel burn but I topped off the tanks and made some trips down to St. Augustine and back and a few river cruises to shake out the boat. I knew I could get more out of diesel than the previous gas boat I had just got rid of. Anyway long story short when I went to top off again I only had 9 gallons of gas in my port tank left out of 100. The port is also where my generator draws from. I did not run out but the gauge read 1/4 tank. I know gauges are not accurate at all but now I know how low I can go.

 

[psneeld]

There's 2 different things going on....low fuel and possibly bad fuel.

Running low on fuel is one thing...as long as you know you have good fuel and know your burn rate..you can take it down to fumes.

The problem with boats is taking it down and plugging up your system from lines to filters to....?????

Thus the reason for day tanks.....

 

[dvd]

I agree that it was most likely low fuel. I think I was suckered into letting it get so low by the calm conditions for a couple of days. I have sight glasses, no fuel gauge, and I let the port tank run down to the 10 gal mark when conditions were flat calm, then switched over to the starboard tank which had 20 gal, thinking I had 10 usable and this would give me over a 100% reserve for my planned 2 hr return. Perhaps if conditions were flat calm on Saturday, this would have been fine, but the weather didn't cooperate and I learned a lesson about how low I can go.

"Experience is merely the name men give to their mistakes." -- Oscar Wilde


dvd

 

[Peter B]

I've never understood why this trend ever developed to have fuel pick-up tubes that end above the bottom of the tank. It means you can never use the whole tank, and guarantees that sludge will form. I guess the one characteristic my boat shares with the Nordys is the fuel drains from the bottom, so there is no chance old muck and water can collect there over time, to just be stirred up and maybe cause clogging in a seaway right when you most do not want that to happen. In effect my filters are polishing the fuel all the time, and yet I get maybe a desertspoonful of water out of the primary filter trap in a year, and the filters always look quite clean when changed, and only need changing once every 5 yrs so far.

 

[rwidman]

I've never understood why this trend ever developed to have fuel pick-up tubes that end above the bottom of the tank.

If they went all the way to the bottom, you couldn't draw fuel out.

Yes, drawing fuel from a sump on the bottom of the tank would seem ideal but most tanks aren't built that way and that sort of arrangement would be difficult to install in many boats. My tanks rest on the inside of the hull. To have a sump, they would have to be raised and that would require additional support structure and reducing the capacity of the tanks.

It means you can never use the whole tank

With a stationary tank on land, one could use "the whole tank" (of fuel). On a boat or a vehicle, there is continual tilting back and forth and side to side. If all the fuel that's left in the tank runs to the end away from the pickup tube, the engine doesn't get fuel.

 

[rwidman]

Someone once said that good judgement comes from experience, and experience comes from bad judgement.

That's partially true, but humans have an advantage over lower life forms by being able to share our experiences with others throught the spoken and written word. Simply put, you don't have to make all the mistakes yourself, you can hear and read about other peoples mistakes and base your judgment on that information.

Humans are also able to reason so we can think "If I do this, what is likely to happen?" This helps our judgement as well.

You have posted your bad experience here and that's good, it's something we can learn from.

Me, I have only electrical fuel level gauges and I have no idea how accurate they are. I get very nervous when they get close to 1/4 full and begin looking for a fuel source. The most I've ever added at one time was 60 gallons with a total capacity of 90 gallons. I would be much more comfortable with sight gauges.

 

[sunchaser]

Some tanks are built to conform to the bottom of the hull. On my tanks the top of the tank is 12 gallons per inch and the bottom slanted portion it is about 8 gallons per inch. The sight gauges are calibrated to take this slanted bottom into account. Further the pickup tubes should be near the deepest portion of the tank acting as a sump design for fuel pickup with all but the last 1/2" or so of fuel showing on the tank bottom rigged sight gauge.

Do not assume the bottom of your tanks are flat. If your tanks are slanted on the bottom, insure your gauges and tubes are so calibrated. A good designer/builder will construct tanks to achieve maximum storage from the available hull shape with pickup tubes so placed.

 

[psneeld]

Most of the bigger boats I have been on including mine have tanks that span internal supports so adding a sump would be quite easy on a new tank...just bottom drawing from many already in place tanks may be easy enough to do if they have an angled bottom...if it's really that important to you.

The trick is to use up your fuel supply every couple of months. In the summer when I sit for 6 or so....I let my supply get low so that it gets circed whenever I do run and well diluted with new fuel/conditioners for when i winter cruise. Not everyone wishes to dothis kind of management and economically it is challenging with guessing when/where to fuel up if you carry a lot of fuel...but all it comes down to is management.

 

[healhustler]

Hmmm. I'm feeling better about my old glass tube gauge all the time.

 

[bglad]

With experience comes understanding... and you don't learn as much doing things right all the time

 

[CPseudonym]

With experience comes understanding... and you don't learn as much doing things right all the time

It's easy to avoid mistakes if ya never try new things. My best life lessons have come through the mistakes made, biggest successes have often followed too.

 

[FlyWright]

I agree...low fuel or excess air, depending on how you look at it. I'm with Edelweis. If I got to 1/4 tank or about 30 gals each tank, I'd be headed for a refill. I'm normally refilling before 1/3 tanks.

Kudos to you for bleeding the system in those conditions. I bet you learned a bit about that process also. Did both engines die and restart initially?? Do you have tow insurance?

I have considered adding a crossover line with a transfer pump to allow single engine operation with the fuel from either tank. It would allow fuel from one side to be transferred to the other to allow one engine to continue operating to get home with low fuel. Your experience has caused me to move that improvement up the list of priorities.

Sometimes experience and knowledge comes from the experience and knowledge shared by others. That's what I love this forum!!! Thanks for posting.

 

[markpierce]

Having four fuel tanks I either transfer more fuel in or change to another tank to supply the engine. When the gauge says "0" there's still some fuel left, but do not count on it.

 

[psneeld]

Hmmm. I'm feeling better about my old glass tube gauge all the time.

you should...if really clear it also lets you see the quality of the fuel about to be used.

 

[psneeld]

With experience comes understanding... and you don't learn as much doing things right all the time

I always liked the sayings that were along the lines of "smart people learn form their mistakes...true genius is the ability to learn from the mistakes of others"

That's why I like these forums...lots of info...good and bad...digest it, research it a little and come out on top hopefully...

 

[dvd]

FlyWright -- I have a single engine. It was interesting working in the ER under those conditions. Not easy, but not as bad as I thought it would be. Over the past year I have spent an awful lot of time in the ER re-doing all the boat systems so I know where everything is and I have all of my ER yoga poses down to be able to reach everything. I just had to be careful working around a hot engine.

Yes, I have tow insurance so it was a pretty low threshold to decide to call them.

dvd

 

[skipperdude]

[ I have all of my ER yoga poses down to be able to reach everything.

dvd[/QUOTE]

That is pretty funny.
gave me a good chuckle.

Sd

 

[FlyWright]

FlyWright -- I have a single engine.

Yes, I have tow insurance so it was a pretty low threshold to decide to call them.

dvd

Don't know why, but I thought you had twins. Gotta love that tow insurance!!

 

[jwnall]

Back a long time ago, when I was drafted (Korean war, which tells you my age!), I learned two important things from the Army.

1. Hit the latrine every chance you get, because you might not get another chance.

2. Take a nap every chance you get, because you might not get another chance.

And now that I am retired and find comfort and and solace in boating, guess I will add another one to that list.

3. Refuel every chance you get, because you might not get another chance.

John

 

[FlyWright]

John,

That reminds me of the 3 rules for aging men:

1. Don't pass up a restroom.

2. Don't trust a fart.

3. Don't waste an erection.

(I have filed these away for the distant future when I might find them useful!)

 

[FF]

"Refuel every chance you get, because you might not get another chance."

And crap fuel will be a smaller percentage of the total in the tank, easier to handle.

 

[Rambler]

And crap fuel......

Bio-Fuel??


Sorry, couldn't help it.

 

[Pineapple Girl]

Bio-Fuel??


Sorry, couldn't help it.

OMG let's not get started on that again.

 

[Capt. Joe]

I've never understood why this trend ever developed to have fuel pick-up tubes that end above the bottom of the tank.

Organization writing our voluntary standards (ABYC / NFPA), Coast Guard and environment regulations do not allow fuel supply, (and vent and fill) lines to be anywhere but top of tanks. It is difficult to get the happy medium, where you can allow sludge to build for a while but not be too far off the bottom. If you don't have daytanks, the trick is to always have enough fuel to never lose the prime, no matter what the seaconditions may be.
You can have a sump that you can manually drain, in which case you can allow pick up tubes to reach farther down.
Conversely, sight gauges must also be fitted with shut-off cocks at bottom (and top) as well, in order to comply.

Many builders install screens at the pick up point on the end of the pick up tubes. I advise owners to remove these screen; in time they will plug up, while otherwise sludge goes right through to the primary particle separator.

 

[psneeld]

The USCG doesn't mandate diesel fuel supply to be from the top....only gas...