Alarm sounded and went into SLOW

[Just Pluggin Along]

Looking for some initial thoughts from people who may have experienced this or are in the know when it comes to these engines.

This is a 150hp Ocean Pro 1995 Twin. Port engine is running fine.

I was out with the family this weekend and on the way back to the marina when this occurred. I had been running around 3500RPM's for 15 minuted then idled for 5 minutes while my little one used the potty. Got back up on plane for a few minutes when I felt the starboard engine drop RPMs and the alarm sounded. It was constant for a approx 10 sec and stopped as I pulled back the throttle. First time this has happened and I didn't think to shut it down to reset SLOW as I was a little panicked. It would run at 2100 fine and with the Port side up at 3200 I could get on plane and proceeded to the Marina. I did check the cooling for good strong stream of water and engine didn't feel overly hot. I tipped it up when back in the slip and nothing was blocking the intake but I neglected to check when it happened. I was a little low on oil but not empty.
Is this an overheat situation? I will check thermostats but they are only 1.5 yrs old, maybe clogged or malfunction? Or could this be something in the wiring or alarm system?
Also, I had the powerpack and sensor replaced mid summer.

Thanks,

JPA

 

[Chris1956]

Re: Alarm sounded and went into SLOW

If it doesn't come out of SLOW mode, presumably the overheat sensor, powerpack or wiring are defective. Those V6 motors also have a shift assist switch that kills spark to 1/2 the motor. You might check that also.

 

[ezeke]

Re: Alarm sounded and went into SLOW

The engine must cool and be turned off to release it from S.L.O.W. once activated. It will not return to normal operation without both.

There is a blocking diode in the harness to prevent S.L.O.W. from activating because of other warning signals.

 

[Just Pluggin Along]

Re: Alarm sounded and went into SLOW

I am going to check the thermostats tomorrow just to make sure they are not blocked or corroded and then run it a while to see what happens. I've owned this boat for two years with no issues like this and the previous owner never had these issues either, it is something new for sure.

Can I do any additional damage by taking out to heat it up?

I am assuming if it is an overheating issue it will go into SLOW again to prevent a catastrophy, right?

If it is the blocking diode what will happen, stay in slow right from the get go?

Thanks for the responses!

 

[Just Pluggin Along]

Update

Update

I had a chance to speak to a very trusted and knowledgable Evinrude mechanic about the situation. He suggested going back out for a test run and seeing if maybe it was just something that had blocked the intake that might have caused the alarm and SLOW situation. I filled my oil (they were lower than usual) and topped off my gas and also checked the raw water intakes before running out. I let it warm up for a few minutes then ran at 3000 rpms for anout 5 minutes and then pushed it to 4000rpms for a few and then up to WOT at aout 5200rpms with no issues. I ran it back to the marina at about 3300rpms over a 5 mile run and still no issues. At this point I am going to chalk it up to a fluke and a good lesson learned. My go to guy said he has seen very few alarm diodes fail and not many more temp sensors go bad so I feel like I should be ok for now.

Thanks for the help as always!

JPA