# Oil Tank Float not working



## Smackdaddy53 (Dec 31, 2012)

I’d check the WIF sensor issue first, those oil tank floats rarely fail.


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## Chad Cohn (Mar 8, 2018)

Smackdaddy53 said:


> I’d check the WIF sensor issue first, those oil tank floats rarely fail.


OK, I'll check that first. Service guy made it sound like it was a normal thing for them to get "water"logged. Sounded kind of odd to me, and than the kick in the pants is the oil tank is $300+.


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## Smackdaddy53 (Dec 31, 2012)

My Yamaha tank level alarm kept going off and I’m not buying a new tank so I just cut the pink wire and make sure to top it off.


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## Chad Cohn (Mar 8, 2018)

Smackdaddy53 said:


> My Yamaha tank level alarm kept going off and I’m not buying a new tank so I just cut the pink wire and make sure to top it off.


I only hear the beeps when I running at a very low speed, hell I'm partially deaf in my left ear anyway. I've been on the google some more this morning looking for some other things to try as well.


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## Smackdaddy53 (Dec 31, 2012)

Chad Cohn said:


> I only hear the beeps when I running at a very low speed, hell I'm partially deaf in my left ear anyway. I've been on the google some more this morning looking for some other things to try as well.


Huh


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## GullsGoneWild (Dec 16, 2014)

My tohatsu did the same thing. Checked everything that the manual told me to check. Took it to my dealer and asked them. They said it was a friendly reminder to change the oil at the 100hr mark. Not sure if yours could be the same thing.


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## mro (Jan 24, 2018)

Disclaimer >>>I'm not a marine mechanic but I have been known to fix a few things 
I will only work on my own marine outboards/engines. Not even for a friend.
One thing you really need is a dependable motor when your out on the salt.

Floats "senders", as they/rise or fall the "sender" changes resistance which you can measure with a cheep analog multi-meter set to ohms. Attach the two meter leads to the two wires of the float, then you need to raise/lower it while watching the meter. This can tell you that sender IS NOT working if the meter needle does not move and if it does move it still may not be any good but most of the time it will be good.

You might be able to carefully fish a wire through the fill port on the tank to raise/lower it. Both cheep analog and digital meters are not very accurate but at least will give you an idea that something else may be the culprit. A quality multi meter will measure accurately and factory should have a spec for this although they are not always willing to share.

If there is only one wire from the float/sender then ground one lead to unpainted bolt or bare metal on the motor and the other lead to the wire. (I've only seen one wire devices that had metal tanks)

If you can't raise/lower the float with a wire (like a coat hanger) then manually empty and fill the tank. This is so you don't have to remove the tank. 

Not sure how they are set up to check for water in the fuel. Most likely it's measuring the electrical conductivity of water verse oil. A multi meter could test this also but without seeing the unit I'd guess that it would have to be removed and bench tested with a meter set to ohms by checking it with water added and without. It should show resistance (increase of ohms) with water and not with oil.


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## Chad Cohn (Mar 8, 2018)

GullsGoneWild said:


> My tohatsu did the same thing. Checked everything that the manual told me to check. Took it to my dealer and asked them. They said it was a friendly reminder to change the oil at the 100hr mark. Not sure if yours could be the same thing.


It's a 2 stroke so I'm not sure that's the case. I'll look into though.


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## Smackdaddy53 (Dec 31, 2012)

Bypass all that shit and premix


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## GullsGoneWild (Dec 16, 2014)

Smackdaddy53 said:


> Bypass all that shit and premix


^THIS


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## Chad Cohn (Mar 8, 2018)

Smackdaddy53 said:


> Bypass all that shit and premix


Been thinking about that too but I am unsure as to how I go about it.


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## Smackdaddy53 (Dec 31, 2012)

Chad Cohn said:


> Been thinking about that too but I am unsure as to how I go about it.


Nevermind, you can’t delete it on an Optimax because it’s EFI. It was easy on the carbed motors.


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## Chad Cohn (Mar 8, 2018)

Smackdaddy53 said:


> Nevermind, you can’t delete it on an Optimax because it’s EFI. It was easy on the carbed motors.


Well, FML. 
I bought this boat a little over a year ago and it seems that a lot of little things are popping up here & there. I know age is a part of it and for the most part I'm confident in doing it myself. Although the steering has been getting a little looser (not crazy loose) but enough for the steering knob to no longer to be in the top position where it was originally. I'm not sure if I want to take that on because the "channel" that everything runs through is super tight and I'm not ready to re-run everything just yet, but maybe this winter but even than I'm not sure.


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## Vertigo (Jun 3, 2012)

Optimax oil tank sensor failure is common and expensive. There are videos online that show how to fix the sensor without buying a tank, but I've tried that approach and it doesn't work too well. As a short term fix, disconnect the wiring harness to the tank and jump the two female sockets...that will shut off the alarm (if the tanks sensor is the problem). The best long term fix is to install a new tank.


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## Chad Cohn (Mar 8, 2018)

Vertigo said:


> Optimax oil tank sensor failure is common and expensive. There are videos online that show how to fix the sensor without buying a tank, but I've tried that approach and it doesn't work too well. As a short term fix, disconnect the wiring harness to the tank and jump the two female sockets...that will shut off the alarm (if the tanks sensor is the problem). The best long term fix is to install a new tank.


That's what I was afraid of.


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## Smackdaddy53 (Dec 31, 2012)

Vertigo said:


> Optimax oil tank sensor failure is common and expensive. There are videos online that show how to fix the sensor without buying a tank, but I've tried that approach and it doesn't work too well. As a short term fix, disconnect the wiring harness to the tank and jump the two female sockets...that will shut off the alarm (if the tanks sensor is the problem). The best long term fix is to install a new tank.


The best fix is buy a Yamaha


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## Chad Cohn (Mar 8, 2018)

Smackdaddy53 said:


> The best fix is buy a Yamaha


Not repowering yet, hell I'm still paying for the boat. 
I guess the main question I need answered is, do I need to change the tank (assuming that is the actual problem) now if I know the engine is using oil properly? The beeping is annoying but like I mentioned above the engine is running like a top right now.


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## Vertigo (Jun 3, 2012)

If the engine is running properly now and getting oil, and you're willing to risk that at some time in the future it may not be getting oil, then you're not going to hurt anything by disabling the sensor. It's a gamble, but the odds are probably in your favor.


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## Smackdaddy53 (Dec 31, 2012)

Vertigo said:


> If the engine is running properly now and getting oil, and you're willing to risk that at some time in the future it may not be getting oil, then you're not going to hurt anything by disabling the sensor. It's a gamble, but the odds are probably in your favor.


That’s why I snipped my level sensor wire. I know i will run my gas tank dry before it injects a full tank of oil and I top oil reservoir and gas tank off after cleaning the boat each trip. A hose rupture or tank leak is the only way it will run out of oil and hopefully the leak would be noticed in time.


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## Guest (Oct 22, 2018)

Vertigo is dead on here! The Merc tanks are known for sensor failures and the engineer that designed it should either be shot or collect royalties for the damn design! The tank has to be replaced pretty much in most cases!


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## Chad Cohn (Mar 8, 2018)

Once this next bout of rain is over I will check on a few things to narrow down the problem. Hoping for the water sensor since it’s the cheapest to replace. Cheapest oil tank I found is $318.


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## Guest (Oct 23, 2018)

The vst should have a drain on the bottom that can be opened with a flathead screw driver. Try draining it and make sure there is no water. I normally don’t say this, but an Opti is best left to the merc tech... things can go south in a hurry if you don’t know what your doing. So be carefull what you touch or change.


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## Chad Cohn (Mar 8, 2018)

So it turns out that I have water in the fuel says the service guys. They want to drain the tank, add 10 gal of gas, change filter and sensor to the tune of $1000. So let me ask, how hard is all of that (mostly the tank draining)? Pretty sure I can do the filter & sensor and several 5 gal gas cans and I have a burn pile that needs a burning. Let me know your thoughts.


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## Guest (Nov 19, 2018)

Should’nt be too bad! I drain tanks through the sending unit hole using a hose and siphon. Once it gets down real low, I’ll use a primer bulb on hose to pull the last of it out. The vst should have a drain that can be opened. Are they quoting to clean injector rails and all? This should be done also if water got to them and I highly recommend letting the pro do that!


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