Motor question

[branthill]

Hey guys, I got a 40 horse Merc, early 90s model. When I turn the key on, it has a continuous beep, like an overheating alarm. I can't get it to go off. Motor runs fine, water pump works great...Just thought I'd post and see if anyone has ever had this problem? Sounds like an easy fix, if I just knew what to look for.

Thanks

[Slipcork]

Oil low problem? don't know. Merc has a web site that you can do a lots of checkin to see what's wrong.

[Slab Rookie]

Sounds like it might be in the alarm sensor itself. It pumps water, is it oil injected or pre-mix. If it has a oil tank the level reading sensor may have sank to the bottom. This happened on my 115 Merc and had to have the tank replaced.

[slabbandit]

The best thing that you can do is get rid of the old oil injection system, if it is one of the old remote kind, and start mixing your oil/gas. Best I remember a steady beep is "overheating". Just because water is coming out the tube don't think that the water pump is pumping properly. If it sputters at idle speed your impeller is missing some blades! This was my problem and I found that out of 6 rubber impeller blades I was down to just one and it was partially broken off!

[Tunica]

could your thermostat have trash in it. When Mine does and it cant clear itself usually caused by seeds then the alarm will go off. One way to tell is the water discharge (pee tube) from the motor. IF your not getting a full stream discharge then the termostat could be clogged. Hope it helps

[DRPEPPER]

There was a thread on this subject a while back. Might be worth digging up. I think it was on the main forum.

I had this happen last year on my 2000 merc. It turned out to be a low oil sensor. I spent a few hundred $$$$ fixing it. I don't know why; I always check my oil and I couldn't hear it. It bugged my guest though.
DP

[CrappieHusker]

branthill
Different kind of motor but: I have a 50 HP Suzuki Fourstroke on my Landau 175 Bass. I had a similar problem with the sensor going off. (sensor is designed to go off after 20 hours and again after 100 hours just to let you know it is time to change the oil) But before I had 100 hours on it the sensor went of, I would shut it down, start it again, then it would be okay for a while, then it would do the same thing again. It was under warranty, so I took it in and they scoped the motor and could tell that this had happened 7 or 8 times. They at first thought it was a sensor problem or possibly a leaf or plastic had gotten inside the water cooling intake on the motor, but eventually said it was a cavitation problem, so they moved the motor down one bolt hole on the transom. Kind of eliminated the problem for a while, but last year the sensor went off about 3 times, but other than that no problems. Have not taken my boat out yet this year but may later today.
Good luck with your problem