FWIW 53MY fuel "reserve"

[MikeP]

Last season I intentionally ran the forward tank out of fuel on our 1980 53MY. A few days ago I refueled and was curious as to how many gallons it took for the oem gauge to get UP to the "empty" hash mark when there was no more usable fuel in the tank. It took 49 gallons of fuel to raise the level to "empty." So there's a good bit of reserve when it hits empty. I have not done this with the aft tank so I have no idea if it is similar I would expect so but can't say…

We also hit 17.8 knots on our way back to the marina today which is pretty impressive considering I had just put fuel in two days prior and we have every possible bit of available space on board filled with something. 18.4K was the best I have ever seen from the boat, when we did the purchase sea trial. But there's been a lot of weight added since we purchased it and the only way it could hit 18 is going down a steep hill.

 

[SeaEric]

The tide runs out of the Chester River at a pretty good clip. That may have helped.

 

[MikeP]

We were just outside the north channel into Piney, running more or less NW for the "speed run" so I was thinking at the time that the tide wouldn't have much effect but we didn't do a two-way run so you are right, the tide could have made a noticeable difference. But the boat ran exceptionally well…maybe the new four-dollar and 3 cent/gallon diesel fuel made the difference!

 

[SeaEric]

Did you get your "friends and family" .25/gal discount at Piney's fuel dock?

 

[MikeP]

Did you get your "friends and family" .25/gal discount at Piney's fuel dock?

Yep, I should have mentioned that I didn't pay MSRP!

 

[saltshaker]

I think it varies depending on the shape of the tank. My 46 had 3 tanks the center tank was 250gls. Lowest I ever ran it was to about 1/8 on the gauge. She only took 165gls. The cockpit tanks were 200gls each. I ran them down to E by transferring fuel to the forward tank. They only took around 150gls each when I filled them. My 65 runs the other way. Cockpit tank is 1094gls. Gauge at half and she will take almost 700gls. First time I found that out Dave and I were coming in for the night and we stopped for fuel. On one of my last ER checks I was surprised to see the gauge had dropped so fast. Switched her to the forward tank and finished the run on that tank. I was expecting to put around 700-750gls in there. She took 950gls! Center tank is similar but not as bad. 450gls and at 1/2 on the gauge she hill take 300gls. I have a reserve tank that is another 130gls and that one seems to react normally. My 46 tanks were on platforms under the cockpit and were rectangular. The tanks on the 65 are shaped to fit in the hull so the top half is definitely bigger than the bottom.

 

[saltshaker]

The tide runs out of the Chester River at a pretty good clip. That may have helped.

I was coming down the Hudson in my 46C from up around bear mountain. Started off cruising around 21kts. By the time I hit midtown Manhattan I was running 24kts. I only burned off about 80gls at that point so it wasn't weight. Speed dropped down to around 20kts when we hit open water. I cruise around 17kts @1700rpms. Heading north in the stream we hit 19.5kts. At one point I hit 23kts at 1950rpms. Would be great if I could do that all the time. Only time I see 23kts at that engine speed is when she's near empty.

 

[Vincentc]

Not all gauges give you a reserve.

I recently started Lilly Marie on an 18 nm trip with the tank tender indicating 1.5" for the aft tank. We were about 3 nm short of home when the stbd engine stopped. I stopped the port engine, changed over to the fwd tank, then we continued on with one engine until I cleared the air out of the stbd fuel line and restarted the stbd engine.

The tank tender indicated 1" when there was not enough fuel to keep the stbd engine running. Approximately 14 gallons of fuel is needed to raise the tank tender gauge 1 inch.

I assume the boat was designed so that one engine would stop first and allow the other to keep running so you could keep power after changing over to the other fuel tank.

 

[saltshaker]

Not all gauges give you a reserve.

I recently started Lilly Marie on an 18 nm trip with the tank tender indicating 1.5" for the aft tank. We were about 3 nm short of home when the stbd engine stopped. I stopped the port engine, changed over to the fwd tank, then we continued on with one engine until I cleared the air out of the stbd fuel line and restarted the stbd engine.

The tank tender indicated 1" when there was not enough fuel to keep the stbd engine running. Approximately 14 gallons of fuel is needed to raise the tank tender gauge 1 inch.

I assume the boat was designed so that one engine would stop first and allow the other to keep running so you could keep power after changing over to the other fuel tank.

On mine the generator will shut down first then the mains. Priming pumps make an oops easy to deal with. Fortunately I've never had to use them for that reason.