Yamaha SHO 250?

First time owning a 4 stroke. 17 model. What do I have to do for maintenance? Oil? 250 on a cat

Oil, filters, and impeller.

This^ and if it starts running rough, not wanting to accelerate, change the spark plugs.

Read the "Engine Owners Manual". That would be where I'd start.

If you don’t know when it was done change lower unit lube. Make sure you use the HD lower unit lube for replacement.

I would assume no maintenance has been done and just do it all now. Something as simple as changing the lower unit grease could show a potential water intrusion issue and save you $3-4K.

Additionally, if you have an issue and you haven't done recommended maintenance they could deny your warranty claim.

Gotta love a 2 stroke... Add oil to the tank and go.

..... and more oil, and more oil...then change the plugs, filters, plug wires, lower unit oil, and
Impeller.

What point are you trying to lake? Haha that a 2-stroke needs nothing, ever? If a 2-stroke was great, you’d still be able to buy one on a bass boat.

Two strokes are loud and smoke. Old technology for boats compared to 4 stroke. One day they will not be allowed on any lake in the USA. I own a two stroke and don’t want to. Just bought a new to me Yamaha four stroke and what a wonderful difference it has made. Quite and sooooo smooth. No stinking oil smell. You can set in the boat and carry on a normal conversation with someone in the next seat without needing to talk over your two stroke. I liked my two stroke until I got my four stroke and I love it. You will too when you get one. If you haven’t owned a four stroke you can’t possible realize the amazing difference. I didn’t but I do now and so does everyone that has a four stroke. Sorry but that is just the way it is.

I don’t care if you have a 2 Stroke or 4 Stroke.. should be doing that service schedule listed above, especially the annual:100 hour service. No personal experience with the 4 strokes yet but like stated previously, everyone I know with one absolutely loves them. I like how quiet they are, but man I do love the smell of a little puff of smoke out of a 2 stroke first thing in the morning.

Newer DI 2 strokes don't smoke and aren't all that loud. Heck the E-Tecs even beat 4 strokes when it comes to emissions.

On that note,my etec would run circles around my 250SHO, was quite and seemed to just sip oil. Ran it for 7 years and it was flawless.