I was checking the archives and in July 1999 I had posted the following on HOW and got the two responses below it. To get my 40.5 ready for transport by truck I let my fuel level get near empty. Then while sitting at the Long Beach shipyard dock waiting for the crane, I ran the engine to get a full charge on the batteries and to also empty some additional fuel. After only 20 minutes the engine quit and I checked the fuel filter and it was dry. It seems to be too soon but that’s cool I thought, the tank is definitely empty and when I get to Texas I can fill the tank and find out HOW much it really holds (true capacity in USABLE gallons). Imagine my surprise when I filled the tank and it only took 34 gallons. What gives? It is supposed to hold 40. Until now, I assumed the tank gauge was off when it indicated empty because the dealer had to bend the float to keep in from hanging up on the side of the tank that made it never read below half. I had thought I still had more than 5 gallons when the gauge said I was near empty because when I filled the tank it would only take around 33 gallons or so. I now realize I was very lucky on some of my crossings to Catalina Island and my trip to Mexico that I didn't run out of fuel. I try to always keep a full tank and refuel if I get down to a quarter of a tank when cruising. I can ‘sail’ into a slip or to a fuel dock but that’s NOT being a prudent sailor. ---- Response from Patrick Magers Several years ago I ran out of fuel in my 40.5. Upon filling the tank, it took approximately 35 gallons. This incident occurred when the boat was approximately 9 months old and therefore the fuel tank was relatively clean. I sailed into the fuel dock, filled up the tank, bled the system and the engine immediately fired up. I had no problems thereafter It’s my understanding that the pick up line will not reach the last three or four gallons in the bottom of the tank. Assuming this to be true, my tank is close to the stated capacity. My boat is a 1994 model. ---- Response from Jim Bohart Actually the tank holds closer to 40 Gals. Its usable capacity is a bit less because the pick up tube does not contact the bottom of the tank but is .5 to 1" off the tank floor. If you have an aluminum tank it should be closer to 40 gals than a roto cast tank which has a thicker wall section but the same external dimensions as the al. The pick-up tube is off the floor to prevent it from sucking up water, algae, slime, and dirt. Maybe it would be more accurate to state usable capacity rather than the actual dimensions. Both responses confirmed what I thought. Well, I thanked everyone for their comments and said I would plan on using 35 gallons as available capacity and that I was thinking about a second tank. NOW in 2002, I still have the same tank and gauge but use jerry cans for extra fuel during our cruising. New questions – What should I have 5 gallons of fuel sitting in the bottom of my tank that I can not use? Sure, I too do not want to suck up water, algae, slime, and dirt but isn’t that why I have a 10 micron Racor. AND to think I have to have 5 gallons of water, algae, slime, and dirt in the bottom of my tank before the Racor even sees it. Both of these thoughts tend to bother me just a little bit. Does it make sense to lower the fuel pickup tube closer to the bottom of the tank to get that additional fuel? PLUS, I just installed a generator with its own Racor from the second pickup in the fuel tank. What if that pickup was lower so if I had a problem with fuel I would know about it when I was running the generator? PLUS, with cross-connect valves, I could switch to the generator's Racor if I got too low on fuel while using the higher engine fuel pickup tube. It should be enough to allow me to motor into the fuel dock. What do you think?
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Rich Stidger
Yup, 34 gallons
Mickey, I remember your post. I was curious also and so I measured the tank with a tape. I calculated the volume of all the different shaped sections, and came up with a volume of 34 gallons. My gauge (when it was working) read nearly empty at about 28 gallons used. I have only once put in about 30 gallons. Regarding the fuel pickups- My understanding is that the pickups are at different levels. The engine is lower than the generator so that the generator cannot consume all of the fuel and leave you stranded (or at least at the mercy of the winds). I would not be conserned about anything left in the bottom of the tank. It mixes with the rest of the fuel and thus should stay as clean as what you are burning. It is not like the bottom inch of fuel just collects crud and stays there forever. However, it would be nice to suck out the bottom of the tank occasionally. Likewise, I would not move the pickup closer to the bottom. I tend to have faith in the people that design things unless there is a glaring deficiency. I do wonder why Hunter would advertise the tank capacity as 40 gallons when by measured volume it is only 34. Is it possible that the previous Hunter 40's had a 40 gallon tank and the spec was just an inadvertent carry-over? Rich
Mickey, I remember your post. I was curious also and so I measured the tank with a tape. I calculated the volume of all the different shaped sections, and came up with a volume of 34 gallons. My gauge (when it was working) read nearly empty at about 28 gallons used. I have only once put in about 30 gallons. Regarding the fuel pickups- My understanding is that the pickups are at different levels. The engine is lower than the generator so that the generator cannot consume all of the fuel and leave you stranded (or at least at the mercy of the winds). I would not be conserned about anything left in the bottom of the tank. It mixes with the rest of the fuel and thus should stay as clean as what you are burning. It is not like the bottom inch of fuel just collects crud and stays there forever. However, it would be nice to suck out the bottom of the tank occasionally. Likewise, I would not move the pickup closer to the bottom. I tend to have faith in the people that design things unless there is a glaring deficiency. I do wonder why Hunter would advertise the tank capacity as 40 gallons when by measured volume it is only 34. Is it possible that the previous Hunter 40's had a 40 gallon tank and the spec was just an inadvertent carry-over? Rich
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Mickey McHugh
Will Check Pickups
Good points Rich. I'll pull the pickups this weekend to find out HOW long they are. Maybe the engine has been using the shorter of the two. If so, I'll connect the generator to the shorter one. While I'm at it I will use my trusty little bronze hand pump and pull some fuel off the very bottom of the tank into one of my 5-gallon fuel jugs to see just what's on the bottom. What are you going to do about your fuel gauge? You said it wasn't working. Let me know if you find something you're happy with. I still have my same problem. The float arm was too long and hung up on the baffle so it would only read empty to half full. The dealer fixed it by bending the arm sideways so it would indicate full but because it was effectively shorter, it also indicated empty when it wasn't. I bent it back. I want to know if I am near empty if I'm making a long ICW run. Not a good place to run out of fuel.
Good points Rich. I'll pull the pickups this weekend to find out HOW long they are. Maybe the engine has been using the shorter of the two. If so, I'll connect the generator to the shorter one. While I'm at it I will use my trusty little bronze hand pump and pull some fuel off the very bottom of the tank into one of my 5-gallon fuel jugs to see just what's on the bottom. What are you going to do about your fuel gauge? You said it wasn't working. Let me know if you find something you're happy with. I still have my same problem. The float arm was too long and hung up on the baffle so it would only read empty to half full. The dealer fixed it by bending the arm sideways so it would indicate full but because it was effectively shorter, it also indicated empty when it wasn't. I bent it back. I want to know if I am near empty if I'm making a long ICW run. Not a good place to run out of fuel.
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Rich Stidger
Pickup assignment
Mickey, I seem to remember that the aft pickup tube is the one that the engine uses and the forward is the one I connected to my generator. I would be interested in the length of the tubes and also how much stuff you find in the bottom. Regarding my fuel gauge- I think the problem is an open connection to the sensor according to the symptoms presented. It could also be a bad sensor. I bought a spare sensor, but physically getting to it in order to check the continuity and/or replace it is a real problem. It is located under part of the vertical walk-thru wall in the cockpit. I'm not even sure I can cut an access hole to get to it. It might be a "pull the tank somehow" job. Do yo know how your dealer got to your sensor to bend the arm? Rich
Mickey, I seem to remember that the aft pickup tube is the one that the engine uses and the forward is the one I connected to my generator. I would be interested in the length of the tubes and also how much stuff you find in the bottom. Regarding my fuel gauge- I think the problem is an open connection to the sensor according to the symptoms presented. It could also be a bad sensor. I bought a spare sensor, but physically getting to it in order to check the continuity and/or replace it is a real problem. It is located under part of the vertical walk-thru wall in the cockpit. I'm not even sure I can cut an access hole to get to it. It might be a "pull the tank somehow" job. Do yo know how your dealer got to your sensor to bend the arm? Rich
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Paul Akers
If you know the capacity...
...of the tank and the fuel burn rate of the engine (in terms of gals/hr), you can calculate (probably more accurately) the amount of fuel left in your tank. This is how I estimate my fuel consumption and remaining amount in the tank. It is far more accurate than the guage that is on the tank, which I only use for a estimating. Also, my L37 has a poly fuel tank and by using a flashlight placed lens-down on the top of the tank, I can see the amount of fuel remaining this way, also.
...of the tank and the fuel burn rate of the engine (in terms of gals/hr), you can calculate (probably more accurately) the amount of fuel left in your tank. This is how I estimate my fuel consumption and remaining amount in the tank. It is far more accurate than the guage that is on the tank, which I only use for a estimating. Also, my L37 has a poly fuel tank and by using a flashlight placed lens-down on the top of the tank, I can see the amount of fuel remaining this way, also.
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Rich Stidger
The burn rate varies....
Paul, Yes, this is how I have been keeping track of the fuel I use. However, at 2000-2100 rpm I use 0.8 gal/hour and at 2500 rpm it is 1.0 gal/hour. My generator uses between 0.3 and 0.5 gal/hour depending upon load. These factors are hard to keep track of and tally. To be safe I just use 0.8 for the engine and 0.5 for the generator and then figure that I have used between that calculated number and 15% more than that. However, every once in a while I am surprised... Oh, yes, this summer my LCD display of the engine hours went blank for a 10 day period on my Chesapeake cruise, then reappeared. No total time was lost, just the display. I had to use my watch chronometer and record each day's usage. Probably another dreaded intermittent....... Rich
Paul, Yes, this is how I have been keeping track of the fuel I use. However, at 2000-2100 rpm I use 0.8 gal/hour and at 2500 rpm it is 1.0 gal/hour. My generator uses between 0.3 and 0.5 gal/hour depending upon load. These factors are hard to keep track of and tally. To be safe I just use 0.8 for the engine and 0.5 for the generator and then figure that I have used between that calculated number and 15% more than that. However, every once in a while I am surprised... Oh, yes, this summer my LCD display of the engine hours went blank for a 10 day period on my Chesapeake cruise, then reappeared. No total time was lost, just the display. I had to use my watch chronometer and record each day's usage. Probably another dreaded intermittent....... Rich
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Paul Akers
Keep a spare jug
Once you figure your capacity, keep a spare jug of fuel. Just this year, when I cruised to Maine, I started keeping a spare diesel jug on deck. It's a 5 gallon jug, but is is comforting to know that it's there. That amount should keep you out of any trouble - just a safety net for those unpredictable woes.
Once you figure your capacity, keep a spare jug of fuel. Just this year, when I cruised to Maine, I started keeping a spare diesel jug on deck. It's a 5 gallon jug, but is is comforting to know that it's there. That amount should keep you out of any trouble - just a safety net for those unpredictable woes.
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