water separator

I've never changed a water seperator and was thinking about doing it on my new used boat. should this be part of a regular maintinance program?
Thank's

Are you talking about a water seperator "under the hood" such as in EFI models or an "inline" filter that was an add-on?

Merc recommends the (on-board) filter be changed every 100 hours or sooner if you get an alarm (smartcraft monitors the filter if you have a smartcraft equipped model).

Particularly if you are running E-10 fuel any in-line or aftermarket filters would definately benefit from being changed as part of your annual maintenance.

Having to paddle back to shore, or get towed on just one occassion because your motor sucked some water and the minimal cost of a filter or two will seem quite small...

Personally, I see no reason why any gas filters, sparkplugs, motor oil (for 4S models) and gear oil shouldn't be changed before the start of "every" season - prevention is always significantly cheaper than cure....

What I should have added to the above is, a single boating season (1 year) is considered to be 100 hours of run time on the "average" outboard (some study group came up with that whose name escapes me).

So when you look at service recommendations in your owners manual, "every 100 hours" would mean 100 hours OR once a year, whichever comes first.

Many outboards don't see 100 hours of actual operation in 5 years much less one. It's these motors in particular that need MORE service - an idle motor will develop problems quicker than one that is running all the time...

Thanks galamb I was refering to the add on filter I didnt even know of another but will read up and make sure all maintinance is done. I dont know what has been done before me so I may as well do it all right now at the beginning of the season

Any Merc outboard with fuel injection (EFI or DFI) has a water sep filter under the hood - usually co-located with the electric fuel pump that the feeds the fuel rails.

So depending on your model you may or may not have one...