1990 90 hp Mercury. Beeping when key turned on.

[lmbr]

This is a project boat. Been sitting for a few years. Will start but not stay running. Thinking carb kits. However the biggest problem is a beeping when the key is turned on. I’m thinking low oil alarm but there is oil in the tank. Am I on the right track? Should I remove the tank, dump the old oil, and clean the tank? What about the low oil sensor?

 

[Chris1956]

What does the owners manual (internet) say the beeping is? Probably an oil injection issue. That motor usually comes with just the engine oil reservoir. Is the float level sensor working? I believe it should ground when oil is low.

A steady tone is overheat.

Obviously you should premix fuel 50::1 until you get this sorted out. Many will advise to remove the oil injection.

 

[flyingscott]

Those are notorious for the sensor in the tank failing. Unplug the sensor wires and see if the beeping goes away. Run on premix until positive the oil injection is working. And get the carbs cleaned before anything else. Those motors do not have a history of oil injection failure.

 

[lmbr]

Will do, thanks. I have a lot to do on the boat also so it is going to take a while.

 

[airshot]

According to my manual, the beep when the key is first turned on is a check to let you know the alarm works. Just a short beep then turns off to let the operator know the alarm is good. This is my first oil injection motor, besides an older Johnson that I knew had injection issues. My research has shown the Mercury oil injection system is one of the better systems on the market. Regular maintenence is required to keep them working well, so I have been told. The previous owner had just had the entire motor gone thru last fall, with receipts, was one reason I bought my rig this summer from him.