2005 200hp Mercury Optimax Water in Gas

[sec56]

I've been boating for 40+ years. All the outboards I've had were either Johnson or Evinrude. My last outboard was 1999 175hp Evinrude (fitch version). After several years the Evinrude quit and after a long discussion with different dealers, I decided on Mercury Outboards. The biggest problem I encountered was that regardless on the manufacturer, there was a 52-week lead time for a loose new motor. So, then I began looking for adequate used motor and ended up getting the 2005 200hp Mercury Optimax rebuilt. The price was far better than buying new, and it only took a week to get it. Anyway, my problem is water in gas the and the water sensor on the outboard is sounding off. Yes, I did have water in the fuel. I drained most of the fuel until I saw no more water. The alarm was and is still sounding 4 beeps every two minutes. I also checked both oil reservoirs to make sure it wasn't low on oil. Oil levels were fine. As for the type of gas, it's always been regular unleaded. I have never used rec fuel in all the years of boating. I added a water separator, which shows no water in the gas. The gas isn't cloudy looking like it did when this problem first began. I've added ISO-HEET to help remove any remaining water that didn't drain. I did not remove my floor or tank mounted gas gauges (two tanks) to if see water remained in either tank. Gas has Mercury's fuel stabilizer, quick kleen, and quick store in it from winter storage. I open to suggestions. I'm going to drain the vapor separator again tomorrow to see if there is any water from either port. Again, any suggestions would be appreciated.

 

[dingbat]

I've been boating for 40+ years. All the outboards I've had were either Johnson or Evinrude. My last outboard was 1999 175hp Evinrude (fitch version). After several years the Evinrude quit and after a long discussion with different dealers, I decided on Mercury Outboards. The biggest problem I encountered was that regardless on the manufacturer, there was a 52-week lead time for a loose new motor. So, then I began looking for adequate used motor and ended up getting the 2005 200hp Mercury Optimax rebuilt. The price was far better than buying new, and it only took a week to get it. Anyway, my problem is water in gas the and the water sensor on the outboard is sounding off. Yes, I did have water in the fuel. I drained most of the fuel until I saw no more water. The alarm was and is still sounding 4 beeps every two minutes. I also checked both oil reservoirs to make sure it wasn't low on oil. Oil levels were fine. As for the type of gas, it's always been regular unleaded. I have never used rec fuel in all the years of boating. I added a water separator, which shows no water in the gas. The gas isn't cloudy looking like it did when this problem first began. I've added ISO-HEET to help remove any remaining water that didn't drain. I did not remove my floor or tank mounted gas gauges (two tanks) to if see water remained in either tank. Gas has Mercury's fuel stabilizer, quick kleen, and quick store in it from winter storage. I open to suggestions. I'm going to drain the vapor separator again tomorrow to see if there is any water from either port. Again, any suggestions would be appreciated.

Could be all the naphtha (additives) setting off the alarm…lol

Did you install a 10 micron coalescing filter with sight bowl and drain or a spin-on?

 

[KJM]

I've been boating for 40+ years. All the outboards I've had were either Johnson or Evinrude. My last outboard was 1999 175hp Evinrude (fitch version). After several years the Evinrude quit and after a long discussion with different dealers, I decided on Mercury Outboards. The biggest problem I encountered was that regardless on the manufacturer, there was a 52-week lead time for a loose new motor. So, then I began looking for adequate used motor and ended up getting the 2005 200hp Mercury Optimax rebuilt. The price was far better than buying new, and it only took a week to get it. Anyway, my problem is water in gas the and the water sensor on the outboard is sounding off. Yes, I did have water in the fuel. I drained most of the fuel until I saw no more water. The alarm was and is still sounding 4 beeps every two minutes. I also checked both oil reservoirs to make sure it wasn't low on oil. Oil levels were fine. As for the type of gas, it's always been regular unleaded. I have never used rec fuel in all the years of boating. I added a water separator, which shows no water in the gas. The gas isn't cloudy looking like it did when this problem first began. I've added ISO-HEET to help remove any remaining water that didn't drain. I did not remove my floor or tank mounted gas gauges (two tanks) to if see water remained in either tank. Gas has Mercury's fuel stabilizer, quick kleen, and quick store in it from winter storage. I open to suggestions. I'm going to drain the vapor separator again tomorrow to see if there is any water from either port. Again, any suggestions would be appreciated.

You could try running it from a separate gas container to see if your problem is in your main tank or the motor itself.

 

[Chris1956]

Optimax motors often have fuel filters, with water sensors mounted under the cowling. Did you empty/replace that one?

 

[muc]

It sure sounds like you still have water in your tank.
Fuel comes out of the tank thru a dip tube, that tube ends one to two inches above the bottom of the tank. Gas is lighter than water so you can have many gallons of water left in the bottom of the tank even though you sucked the tank “dry” thru the fuel line. This water just sits there until you hit a wave, accelerate or make a turn, then it gets sucked up. Also by using gas with alcohol and adding all these chemicals you are now contaminating the gas your engine uses to lubricate the crankshaft and bearings —— killing your engine from the inside.
The best way to get the water out is to remove the fuel sending unit, jack the boat up so all the water runs to one corner and suck it out. A short section of flexible copper tubing (so you can bend it to reach that corner) connected to some clear hose (so you can see what’s coming out) connected to a pump that won’t start a fire Works good for me.

 

[sec56]

I did install 10-micron separator with a site bowl. No signs of water in the bowl and the gas is not cloudy either. The fuel I've drained is running fine in my other gas engines with no problems. This is my first Mercury and I'm not sure how much fussier the Optimax is. I did drain the vapor separator. This is where I initially found water in the gas. Also, I replaced the gas filter in the vapor separator. I will drain the vapor separator again to check for water. I also plan on checking the water sensor further just in case it could be bad. The Optimax seems to preform fine with the exception of the alarm (this is also affecting my 15hp H.O. Evinrude after it gets warmed (they both feed from the same tank(s)). I also replaced the 15hp gas filter too. I'm not 100% sure I'm looking for the correct cause of my problem yet but feel I am since both outboards are having a problem with the same gas. I do have dual tanks, a 52 gallon and a 30 gallon. Both tanks were mostly drained, but not 100%. Both were treated and both run through the separtor. I still suspect water in the fuel system(s). Just a thought, I do have a 6-gallon Evinrude/Johnson fuel tank. I think I'll hook both motors up to it separately to see if this ends any or all issues I'm seeing.

 

[sec56]

MUC, my Optimax is direct fuel injection, so except for blow by past the rings, I don't know if there is any effect to internal moving lubricated parts from the chemical additives. I don't normally use additional chemicals other than what Mercury Marine recommends. I may use Stabil Marine fuel stabilizer versus Mercury's fuel stabilizer.

 

[muc]

MUC, my Optimax is direct fuel injection, so except for blow by past the rings, I don't know if there is any effect to internal moving lubricated parts from the chemical additives. I don't normally use additional chemicals other than what Mercury Marine recommends. I may use Stabil Marine fuel stabilizer versus Mercury's fuel stabilizer.

Yes, I was wrong about the fuel getting in the crankcase. It's been along time since I worked on an opti. I was thinking normal 2 stroke. I'm guessing a little fuel enters thru the ports in the cylinder walls.
But contaminated fuel is still a problem. The fuel injectors are $300 ea. and the direct injectors are $750 ea.

The water separator won't catch water that's mixed with alcohol, the filters won't catch it either.
Really think you should clean your tanks. The opti has proven itself to be a bit of a touchy engine. They can be a great engine with the proper service.

 

[sec56]

I found today that even though water mixed in isopropanol alcohol, Mercury's WIF sensor can still sense the water in the mixture even though it's not visible in the bowl of my fuel/water separator. So, it looks like an upcoming tank drain (2 tanks) of approximately 80 gallons. I'll run it through my less fussy gas-powered engines. Thanks for all the help and comments.

 

[dingbat]

I found today that even though water mixed in isopropanol alcohol, Mercury's WIF sensor can still sense the water in the mixture even though it's not visible in the bowl of my fuel/water separator.

Sounds fishy...... good quality coalescing filters are 98% efficient at removing water.

I suspect the sensor is contaminated. Pull the line to your primer bulb and drop it in a gas can of fresh fuel.
If the alarm is still there, the sensor is contaminated or needs reset

 

[sec56]

Dingbat, as stated above, I had added isopropanol alcohol (ISO-HEET) to my gas. There is no visible sign of water in the bottom of the bowl on my water separator, no cloudiness either. No sign of water when I drain gas into a glass container. The filter is 10 microns. Should the WIF sensor still be able to sense water in the gas when there is no sign of water accumulating in the bowl of the separator? I also drained the Vapor Separator on the Optimax. the forward drain had very little gas come out (no visible water) but the rear drain had about 1.5 cups of gas come out with no visible water here either. I was going shut off both my tanks below the floor and connect a fresh 6-gallon tank of gas to the separator and see if the WIF sensor still says there is water in my gas. You mention "resetting the WIF sensor." Reset how, if not contaminated? Hopefully, I can get to working on the fuel problem today if time permits. Too much going on right now.

 

[dingbat]

Dingbat, as stated above, I had added isopropanol alcohol (ISO-HEET) to my gas.

Running isopropanol through a moisture sensor probably wasn't the best move. Could have damaged or contaminated the moisture sensor.

Should the WIF sensor still be able to sense water in the gas when there is no sign of water accumulating in the bowl of the separator?

Just because you don't have water in the bowl doesn't mean the fuel isn't carrying mositure.

The sample I took out of my fuel this Spring did not show water either. Left it on the shelf in the barn exposed to the daily temperture fluxations for a couple days. Came back to find @ teaspoon of water in the bottom of a 16 oz. water bottle.

Take a fuel sample and put it in the freezer for a couple of hours. As the fuel cools, any moisture will begin to fall of out solution and collect on the bottom of the container.

Sensor wise, I have no idea what moisture content the sensor is designed to alarm. I would assume it would be greater than 0.5% to prevent false positives running e10, but we don't know

I was going shut off both my tanks below the floor and connect a fresh 6-gallon tank of gas to the separator and see if the WIF sensor still says there is water in my gas. You mention "resetting the WIF sensor." Reset how, if not contaminated? Hopefully, I can get to working on the fuel problem today if time permits. Too much going on right now.

The reason I mentioned fresh fuel from a can is to remove all possibiltiy that the fuel/ isopropanol mixture in your fuel tank is the source of the problem.

 

[airshot]

Check your fuel from the source, many stations do not maintain there tanks like they should ( to busy to do proper testing) even big name stations!! When I fill my boat, I often add some gas to a small clean container to test at home to be sure the fuel is not contaminated. Our city is currently in a lawsuit with a big name fuel supplier for having an excess amount of water in their fuel tanks that has caused lots of issues with peoples vehicles.

 

[sec56]

Update, my Evinrude/Johnson 6-gallon tank leaks fuel at the connection point, with or without a hose attached. At this time, since parts for this tank (fuel gauge) are no longer available, it's junk. So I bought a used plastic outboard 6.6-gallon fuel tank. Although it was dry inside, I had to clean some rust scale inside the tank from the fuel level gauge cap. After cleaning and a new cap, I filled it 1/2 full with fresh gas and connected it to my fuel/water separator. The Mercury Optimax was still giving me the 4 beep alarm every two minutes. I disconnected the WIF sensor and still was getting the 4 beep alarm every two minutes. After further research, I found that the float in the oil tank mounted on the side of the motor can become oil saturated and can give me a false alarm but potentially critical. When I opened the tanks top cap, oil would come out showing me it wasn't low. The Optimax's guardian mode never kicked in due to the low oil alarm, which was not low. I figured the rebuilder used a used oil tank based on the tanks stained blue coloring, so I have no idea how old it was. Those unfamiliar with this tank, it's opaque, (difficult to see though the opaque tank) you should still be able to see the oil level. I replaced the oil tank yesterday, purged the air, ran the Optimax, and no more alarms. Now I'm wondering if water in my gas was really my initial problem or not even though I did have water in my gas. Low oil and/or water in gas alarms are the same, 4 beeps every two minutes on my Optimax according to the literature I have. It's too bad Mercury Marine doesn't set up separate alarms for each potential problem instead of having the same alarm for two totally different problems. Maybe the new(er) outboards do have individual and different alarms. Anyway, I appreciate all the suggestions and information. Next is to take my boat out on a local lake to make sure everything is ok before I go out any great distance on Lake St. Clair or Lake Huron. Have a great day and again thanks to everyone.

 

[dingbat]

Now I'm wondering if water in my gas was really my initial problem or not even though I did have water in my gas. Low oil and/or water in gas alarms are the same, 4 beeps every two minutes on my Optimax according to the literature I have. It's too bad Mercury Marine doesn't set up separate alarms for each potential problem instead of having the same alarm for two totally different problems.

Found this....seems the beep code is not related to the problem rather than announcing a critical or on-critical alarm

Two types of warnings are used on recent production engines:

SOLID TONE: Critical Warning (shut engine down, serious problem present)

FOUR BEEPS: Non-Critical Warning (Proceed to port, get engine to dealer for service as soon).

In either case, there are literally dozens of potential causes. A Smartcraft Instrument may help by giving an indication of what the fault was.

Get your engine to your Local Mercury Dealer, for Computer Diagnostic System print outs of the:
-Run History
-Freeze Frame (Fault) History
-Fault Seconds Counters

Information in these reports will help to determine what fault was occurring, and can assist in accurately diagnosing the cause

 

[Chris1956]

You are using a 6 gal tank on a 200HP engine? Thats about 20min usage tops, at high speed. You might put a proper fuel tank on your wish list. They have 12 and 24 Gal portables

 

[sec56]

6-gallon tank was just for test running here in the driveway. Forward 32-gallon tank has fresh gas a stabilizer in it. Ran it today in Lake St. Clair. No alarms or issues with the 200hp Optimax. But the Evinrude was giving me a problem shortly after it got warmed up. But that's a new post. Have a great day.