Mercruiser alpha 1 gen 2 alarm sounding

[Debruin13]

After pulling my 2006 Sea Ray 180 sport out of storage this year (professionally winterized), I ran through all on-land process and testing. All systems seemed go! After dropping into water, and return to my dock, after running WOT for a minute, the alarm sounded. All gauges seem normal. Oil pressure around 40, temp around 170, gear lube reservoir was a little low, but still above fill line. I have since added gear lube to reservoir and it’s still happening. Also noticed on latest test that it would occasionally alarm when I turned sharply after slowing down a little. Any ideas? New impeller? I’m attaching video. Sorry it’s so short. Kept telling me it was too long.

 

[alldodge]

Welcome
Looks like your over heating

When was the last time the impeller was replaced?

 

[Alumarine]

Even with the short video you can see the temp gauge go up slightly.
You could disconnect the wire at the temp alarm sender and see if the alarm goes off just over 170.

 

[Scott06]

would agree it might be overheating, although I'm not sure what temp the switch goes off at

the alarm is trigger by three things - high temp, low oil pressure, low drive lube. disconnect them and one at a time reconnect them to see which one is triggering it.

these are switches separate from senders on oil and temp for gauges. The switch makes the ground side connection for the alarm buzzer.

 

[Debruin13]

Welcome
Looks like your over heating

When was the last time the impeller was replaced?

“Like 3 years ago” was the response from previous owner. I bought it at end of last summer. I bought the kit to change it out, as I understand they should be replaced every 3-5 years. Right? This I my first speed boat so I’m still learning.

 

[Bondo]

“Like 3 years ago” was the response from previous owner. I bought it at end of last summer. I bought the kit to change it out, as I understand they should be replaced every 3-5 years. Right? This I my first speed boat so I’m still learning.

Ayuh,....... Or, at the 1st sign of overheating,......

Welcome Aboard,.......

 

[Stinnett21]

Carbed or MPI? A few things to check:

• Cross check your temp gauge with a IR gun. Point it at the thermostat housing. Is it close in reading vs the gauge?
• Drain your gear lube enough to empty the bottle. How much gunk is in the bottom of the bottle? Remove and clean if necessary.
• If MPI is your battery the correct CCA rating? My MPI calls for at least 800 CCA. My boat was sold with 625 CCA. Used to get occasional alarms. Replaced with 1000 CCA alarms went away.
• Again if MPI, replace the IAC muffler and clean flame arrestor.

 

[Stinnett21]

After a hard run he gets an alarm. Remnants of exhaust shutters blocking exhaust passages, BTDT. With the alpha the relief ports on each side of the drive are enough to handle normal running, but not at WOT.

 

[Scott06]

“Like 3 years ago” was the response from previous owner. I bought it at end of last summer. I bought the kit to change it out, as I understand they should be replaced every 3-5 years. Right? This I my first speed boat so I’m still learning.

that is a decent rule of thumb but I have found the OEM impellers last much longer in fresh water use. I have never let mine go this long but I changed a 11 year old OEM impeller on my neighbors boat a few years back. Was the original impeller no signs of high temps, was a perfectly good impeller.

I did mine after 5-6 years /300 hrs and there was nothing wrong with it.

I would verify which alarm is sounding off first. My boat with a 160 stat runs 170-175.