I am a moron and freaking out

[oba97]

Just bought a new boat with a new merc 150 4 stroke. Had a hell of a time reloading on the trailer because of the wind. In all my excitement I forgot to shut the motor off (it is way quieter then my old 2 stroke.) I pulled up the ramp to check how the boat was sitting on the trailer when I realized I didn't shut it off. I don't think it ran out of the water for more than 30 seconds. Did I royally screw up? Do I need to replace the impeller or should I be ok? Thought (other than my stupidity)?

 

[ondarvr]

At 30 seconds probably not, it would take longer to overheat the motor, and it would sill have water in it until you shut it off.

The impeller can survive that too, but is it worth the risk? just replace it, it should be done every couple of years anyhow.


​I had a friend not notice he left the motor running until he got home, a new water pump and it ran fine.

 

[oba97]

Ya, I'm not too concerned about the motor, but am with the impeller. Having said that I just hooked it up to the muffs and had a strong stream. I still can't believe I did it. I would not call myself an advanced boater but I have trailered a boat for about 2 years. This is a brand new motor. This was only the 3rd time running it.....I hate the thought of dropping the lower unit already.

 

[racerone]

Time to install a new impeller !!

 

[tpenfield]

Yea, I did that with one of my outboards . . .it was fine.

 

[oba97]

If I had a strong stream on muffs should I still replace the impeller?

 

[tpenfield]

If I had a strong stream on muffs should I still replace the impeller?

The muffs tend to put the hose pressure up through the cooling system, so not a good evaluation of the impeller. I would run the motor in the water and keep an eye on things. A precaution would be to replace the impeller, but it is your choice to make that judgement call.

 

[redneck joe]

a coworker just bought a $50k new Crownline. First time on the water all was well, putting back on the trailer went south - scratches, dinged prop, scratch on another boat - all the good stuff.

and she forgot to turn off the motor.

Don't feel bad, we all do 'things'

 

[ajgraz]

I would replace the impeller. Gonna have to someday, might as well get the practice.

 

[oba97]

is there anything different about changing a impeller on a 4 stroke than a 2 stroke? I have changed one on an old 2 stroke but that's it.

 

[ondarvr]

If it was actually 30 seconds you are probably fine. This isn't the same as starting the motor out of the water when the impeller is dry, the cooling system is still full of water, and since the impeller doesn't pump air all that well, and the impeller is already wet, and with water in the housing, there will still be some water in the pump.

​So most likely it wasn't run dry...but...on the other hand, with a new impeller you may sleep better.

 

[BrettNC]

If it is still pumping water then don't worry about it and enjoy your boat.

 

[tpenfield]

If it is still pumping water then don't worry about it and enjoy your boat.

​That's right .. . enjoy the boat . . . chances are within a short while you'll do something else to the boat and will forget all about this incident.

 

[oba97]

Ya, I'm sure it won't be the last!

 

[444]

Impeller will be fine, it was still wet and had some lubrication when it was running. Like said, this is not as bad as starting it dry.

 

[oba97]

I took the boat out last weekend and everything went fine. No issues with the pee stream and no overheating issues. I think I'm good to go!