Mercury 200 EFI Oil Alarm Issues

I have had my motor worked on twice because the oil alarm will not stop going off. The tank on the motor with the float was completely replaced as well as the cap on the main reservoir. I have used the boat a few times while the alarm is going off and the tank on the motor keeps oil in it at all times. Any suggestions on what could be still causing the alarm to go off? My only other guess at this point is a fault alarm system.

Without a system schematic I/you will be guessing. Normally it is just the engine oil tank cap sensor.

Your mechanic should continue to work the problem for you (no charge) and contact Mercury and your boat Mfg. for assistance/schematic's. If they won't do this, take it to a different shop specializing in Mercury Outboards.

Are you sure it is oil alarm? Is it solid tone or beeping fast? What year model

Model # of your motor? Sounds like you have a 3 liter by your description of replacing the oil tank.

Beeping fast.

I also changed out the fuel/water separator thinking that may be the issue but no luck.

Not 100% sure. Its a 2000 year model 200 EFI.

The numbers off of the tag on the transom mount

It will be either the oil level in the engine oil tank or water in fuel if it is water in fuel there is a red led light at the bottom of ecu a little black box and when the horn sounds the light will flash that is the way to tell the difference in oil or fuel.....OPTI

it also could be a striped crank gear and the oil pump not turning

Don`t think the 2000 has a rotation sensor. Also this year when it gets a water alarm it beeps 4 times every minute or so.

The boat is back in storage and I dont know when I will have a chance to go back and look at the model #. I was just curious what some other suggestions may be. The alarm is beeping non stop the entire time the motor is running so I assumed it was the oil alarm. I will have to look into the striped crank gear.

Mine is doing the same thing. I've replaced everything that you have and still getting the alarm. If you happen to figure it out, please post an update here.

Mercury stopped putting the motion sensor on the oil gear in 1999 so if it is intermediate horn it is water in the fuel because the oil float switch has been replaced......OPTI

if tha thing starts "singin' instantly when key is turned on then ya probably gotta bad module.. it can and will go through tha "self test" then never stop untill ya turn tha key off.. although "normally" but not held as"fact" a bad module will generate a "solid" tone same as overheat.....

The alarm starts sounding as soon as the key is turned. They motor doesnt even have to actually be on before it starts. The alarm is a beep and not a constant tone.

disconnect tha sensors one at a time... buzzer should stop when ya get to tha right one, motor tank cap, water in fuel (sensor on bottom of spin on filter), don't think yours will have rotation sensor ... if doesn't stop at all then ya probably gotta bad module... wouldn't hurt ta use a "mix" of 100 ta one till ya get it figured out.....

Is this a 3.0 Liter or a 2.5 Liter if its a 3.0 Liter it either a bad new float in the tank or sensor and if it is water in fuel there is no led light. If it is a 2.5 liter then water in fuel the led light will flash as horn flashes.....OPTI

I asked the same question because he said he changed the complete oil tank.

plain jane efi 200 3.0 not to common.. i guessed 2.5!!!

Agree but being in Houston area, a lot more salt water motors

I had this problem mechanic said it was due to using ethanol fuel gear being plastic?it also could be a striped crank gear and the oil pump not turning

this pretty much rules out an oiler gear failure.....

first 3.0 200 efi was 2003....

did ya find tha problem?....