outboard beeps at high speed only

my mercury 150 xr-6 beeps only at high speed, could this be bad poppet valve or something else.please help

Is it one long beep, or a series of beeps.

In general, a continuous beep is the overheating alarm, and a series of short beeps is the low oil alarm.

I have the same problem, But I found out it was not getting enough water to the intake at high speed, trim it down just a little and the alarm will shut off. I have a merc 200.

You got 2 thread going right now, but I’ll adderess them both here.

First off do you know what the alarm sound means??? (I’m not familar with merc.)I suspect you are overheating.

Do you have a water pressure gauge? how old is the impellar? Bad thermostat?

Not familar with poppits on a Merc, but it’s in the back of the motor on the bottom on my yamaha. Does Merc have an online parts catalog? I bet if they do it’ll show the valve’s location.

Otherwise wait til Jon Jordan comes in, I believe he ran this motor for years, seemed to like it alot. Someone here should be able to help you a bit better.

hey guys, im back had to make kids breakfast.Im located in hot springs,arkansas.i hear one long beep and shuts off when slowing down.the merc is mounted on 5inch setback jackplate and raised 4 inches high,could this be culprit also.thanks

Sounds like you “may be” a bit high for the water intake, and you are not getting enough water pressure to the motor, really if you’re running a jackplate you need a water pressure gauge. Water pressure is a major factor that will determine how high you can go with the motor on the plate.

I really do suspect you are overheating, and probabaly because the motor is so high, lower the motor a couple inches, get yourself a water pressure gauge and then start raising it up again to find a sweet spot between preformance and water pressure. I would guess motor height is cause the issue more than anything, but you won’t know without the gauge.

Did I mention to pick up a water pressure gauge Money well spent trust me, and they shouldn’t be too spendy or hard to install. Probably a 2 beer job

thank you.I dont have water pressure gauge and i,m gonna take your advice and purchase one

the impeller kit,spark plugs,fuel filter,lower unit oil,and new warning horn installed three days ago

I sent you a Private message too, you should see a little flashing envolope up top next to logout, click on that.

if poppet valve is the problem i would like to fix it myself.the mechanics here are really proud of themselves.the problem is i don’t know where to locate it on outboard

Merc XR-6 has 2 alarms. The constant BEEEEEEEEEEP is the over heat alarm. The BEEP BEEP BEEP is the oil alarm.

Sounds like you are overheating at WOT.

-J.

-J.

Yup, I bet you’re overheating too. That’s what my Merc did to me one time. Once we slowed down, no problem. Putting in a new thermostat should be pretty easy.