New boater advice

[Carolina_Boater]

Hello. I am new to boating. I just bought a used 24ft pontoon boat with 1990 90 hp 2 stroke Evinrude. The motor was run in a barrel of water for demonstration when I first looked at boat. Ran fine.
My issue is I know nothing of outboard motors, their fuel system, and oil system. Boat has 2 25 gallon fuel tanks, and a small oil tank. I was told the oil is injected while motor is running. Would it be safe to premix gas anyway, just while I am learning about the motor's operation?
I now know I have a lot to learn. The boat has not been run since July 4th 2015. What do I need to check before I put it in the water? I am handy with a wrench, and can read directions. I do plan on getting a manual today. I can do routine maintenance. Just from a few minutes of reading other posts, I can see I bit off a big chunk. I want to do things right. I don't want to ruin my motor on first trip to the lake. All advice, suggestions, and words of wisdom will be appreciated.
P.S. I live near lake Murray in SC.

[Solarman]

Congrats, and welcome to this forum. It is a bit of a bite for your first boat. Hopeful that some of this will help you enjoy your investment for many years.

First off, always use muffs with water on anytime you turn motor over. The water pump impeller is water lubricated, and if run dry for a couple of seconds could destroy the impeller.

Adding oil (pre-mixing, and having oil injection) will over oil motor and cause it to run poorly. The oil injection system if working properly will be enough. If you wish to pre-mix, then you should disconnect the oil injection system by the book, or per the evinrude mechanics method, to prevent the computer from shutting the motor down due to its safety protection features.

It is best to keep boat out of water if not used every couple days to prevent algae/ other growth forming on pontoons.

An additive in each tank of fuel (Seafoam, WalMarts- under $7/ can) is a good idea. Especially if using ethanol fuel.

use up all fuel in tanks before storing for winter, and run fuel out of motor, or drain fuel system by manual before storing. Or, you could make it a habit to hook up the water muffs to lower unit every month, or two at the most, and run it a good fifteen to twenty minutes, to flush the old fuel out of the motor, which also heats up any moisture in the motor, and re-lubricates all the internals (to me this is the best thing to do). And if you have a portable (small tank), you could add a little extra oil, just for this approach. It will only help protect the internals when not used much. Also, boosts battery when run.

Also, inspect gear oil before storing for winter, if clear and good (not milky colored-indicates water in oil), is ok to store. If water is in oil, it might freeze and crack the gear case (not cheap/ good). Should change this oil every couple years when getting ready to use it/ after winter is over.

If possible to cover, this would help keep deterioration/ fading down a lot.

Good luck, happy boating, lake Murray is a beautiful lake, loved fishing there.

Contact us at first signs of any problems.