New Boater/ Fuel Gauge broken... How many hours/miles can you get on a full tank of gas?

Oceangeek

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Hi there.
I have a 1996 Adventurer 208 with a 96' 200HP Yamaha Saltwater series 2 stroke engine. The Gas tank has 82 Gallon capacity. The fuel gauge does not work, and I do not have a lot of time under my belt to accurately know how much fuel I am burning after trips. I want to be able to take the boat on longer trips, but I am nervous about not knowing how much gas I have in the tank.
Does anybody have any solutions for knowing how much gas I have in the tank without the gauges? Ive tried a dipstick, but it does not get all the way down in the tank, plus I do not want to be putting a salty stick/wire down there every time to check...

I just took it into the mechanic to fix my fuel gauge. He replaced the sending unit and told me that I need to "recalibrate" the Tach in order for it to work. After hours upon hours of searching I cannot find anything about doing that for a 1996 Yamaha Tach. My 1996 model does not do anything when holding the "mode" button for 4 secs.
The gauge speedometer works great, and all the other gauges, so I feel all the electrical and gauges should be fine.
If anyone has any information on how to fix fuel aspect of this gauge please let me know!

Thank you in advance.
 
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seasick

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I kind of doubt it is the gauge if that is the standard round digital type. There is no calibration for levels, If the sender is good, there must be a wiring issue. The sender ground connection and/or the tank ground connection may be bad.
To test the gauge, open the access plate over the sender, find the pink wire that connects to the sender. Pop that connector off. Leave it loose but not touching metal. Turn on the ignition, no need to start the motor. The gauge should self test if digital and then read empty. Now touch the pink wire to a ground. Try the tank first. If the ground and the wiring and the gauge are good, the display will now read full. If it does, the new sender is not working (assuming you used the tank as ground.
The system is pretty simple.

As to fuel consumption: I have a 208 with a 150 SX motor. For estimating range, I assume that my motor burns about 12 gal per hour at cruise (4000 revs or so) and up to 20 GPH at WOT . That includes a safety factor. The actual consumption is affected by load, sea and wind, bottom condition, hard top or no hardtop, curtains up or off etc

In general the SX motors are gas guzzlers. Also note that with gas weighing about 6 pounds a gallon. a full tank versus a half tank is like carrying a 1 larger extra adult or several children. My point is that if you are not going on long trips don't always fill the tank. You are paying to haul gas :)
 

Parthery

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There is no recalibration on that tach.
Two wires connect to the sending unit.
 

DennisG01

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You can do the same trick that Seasick mentioned behind the dash to test if the wiring between the tank and the gauge is the issue and/or the gauge, itself.

Just to throw out some more numbers, even though it's not exactly apples to apples, but it should help. Running around 3,800RPM, give or take, puts me around 29mph and 11gph with a medium load and relatively fair conditions.
 

Oceangeek

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I kind of doubt it is the gauge if that is the standard round digital type. There is no calibration for levels, If the sender is good, there must be a wiring issue. The sender ground connection and/or the tank ground connection may be bad.
To test the gauge, open the access plate over the sender, find the pink wire that connects to the sender. Pop that connector off. Leave it loose but not touching metal. Turn on the ignition, no need to start the motor. The gauge should self test if digital and then read empty. Now touch the pink wire to a ground. Try the tank first. If the ground and the wiring and the gauge are good, the display will now read full. If it does, the new sender is not working (assuming you used the tank as ground.
The system is pretty simple.

As to fuel consumption: I have a 208 with a 150 SX motor. For estimating range, I assume that my motor burns about 12 gal per hour at cruise (4000 revs or so) and up to 20 GPH at WOT . That includes a safety factor. The actual consumption is affected by load, sea and wind, bottom condition, hard top or no hardtop, curtains up or off etc

In general the SX motors are gas guzzlers. Also note that with gas weighing about 6 pounds a gallon. a full tank versus a half tank is like carrying a 1 larger extra adult or several children. My point is that if you are not going on long trips don't always fill the tank. You are paying to haul gas :)
Thank you for all the the info. Huge help. I am taking it back to the mechanic and we are going to see if it is a grounding issue.
 

Oceangeek

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You can do the same trick that Seasick mentioned behind the dash to test if the wiring between the tank and the gauge is the issue and/or the gauge, itself.

Just to throw out some more numbers, even though it's not exactly apples to apples, but it should help. Running around 3,800RPM, give or take, puts me around 29mph and 11gph with a medium load and relatively fair conditions.
Awesome. Thank you... Do you have the same engine? 200HP Saltwater series?
 

DennisG01

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I have a 250, but if memory serves, they're both based on the same block. Still not apples to apples, but bigger boat/bigger engine vs smaller boat/smaller engine is probably close enough as makes no difference.

Just out of curiosity, does my signature not show on your screen? I have that info listed in my sig, but it doesn't help if no one else can see it! If you're on a phone, does it make a difference if you hold the phone sideways?
 

Oceangeek

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I have a 250, but if memory serves, they're both based on the same block. Still not apples to apples, but bigger boat/bigger engine vs smaller boat/smaller engine is probably close enough as makes no difference.

Just out of curiosity, does my signature not show on your screen? I have that info listed in my sig, but it doesn't help if no one else can see it! If you're on a phone, does it make a difference if you hold the phone sideways?
Thanks for the info.... Yes I just saw that your information does show the model, make and HP. My mistake. I am new to this thread as well as to boating. BTW we figured out the problem. It was the gauge. Very strange that the gauge speedometer and everything else worked, however for some reason the gas was not working on it. Instead of me getting a new gauge altogether I am just going to put a toggle gas gauge right next to it. Problem solved!
 

seasick

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Thanks for the info.... Yes I just saw that your information does show the model, make and HP. My mistake. I am new to this thread as well as to boating. BTW we figured out the problem. It was the gauge. Very strange that the gauge speedometer and everything else worked, however for some reason the gas was not working on it. Instead of me getting a new gauge altogether I am just going to put a toggle gas gauge right next to it. Problem solved!
So the gauge was bad. hmmmm. Next time that mechanic tells you that you need something, get a second opinion. The empty/full test should have been performed before the mechanic determined that the gauge was bad and replaced it.
 
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dstarok

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Rule of thumb- divide the hp by 10, that’s about what you will burn gallons per hour at wide open. Since you probably won’t be running wide open all day, that should keep you from running out of fuel at least.