Running outboards at the slip Is

[GasCan II]

Hello, I purchased my first outboards this season,the boat is in a slip and it has two Yamahas 150 hp Hpdis.Every once in a while I would start the motors up in the slip and let them run for 15 to 20 minutes than shut them down and flush them out.
A friend told me not to do this because they are not getting up to temperature and will have moisture in them and this is not good. Is there any truth to this? Do I have to take the boat out every time I start the motors?
Thanks for any help with this.

 

[robert graham]

A 20 minute run at the slip seems like a good idea to me.....probably not as Good as a high speed run down the river and back.....but better than not running motors at all......A good idea is to always add a fuel stabilizer like Stabil or similar to your fuel tanks to keep fuel fresh

 

[Faztbullet]

Your friend is mistaken....You have DI motors and they will not make moisture but a 4 stoke engine can

 

[dingbat]

Waste of time and money idling an outboard in the slip.

What are you hoping to accomplish?

Alternator output in minimal at idle so your not charging the batteries.

Not circulating the oil as you would with a 4 stroke.

 

[Sea Rider]

Are you running both motors in a saltty or fesh water slip ? After a 20 minute run at idle thermos are opening and closing and motor varying its internal temperature along being well lubricated with the right oil amount for such low rpm...

Happy Boating

 

[GasCan II]

Thank you for the responses , Ding Bat, I don’t do this often, just when the weather or something keeps the boat in the the slip.