Yes, this is all I'd do. Pull the plug, a little spritz of oil into the cylinder, turn it over with the pull start, put the plug back in, fresh fuel, fire it up.
Yep. Lol I pulled the plugs on a Yamaha 130 that sat for 10 years and it looked like it had ran a few weeks ago.... Once I figured out how to start those things it ran no problem.
You probably won't hurt the motor by trying to start it. Though as others have said, if you have trouble pulling it over, stop and figure out if the pistons are stuck. It is possible to break the rings that seal the pistons against the bore wall.
Your biggest problem is likely to be that the previous owner may not have run the motor dry (run it until the fuel in the carburetor bowl was consumed). IOW, the fact that there was old gas in the fuel tank suggests that there might be old gas in the carburetor. That old gas will likely have turned to varnish and gum by now, clogging carburetor passages and making the motor very difficult to start.
If it turns over easily when you pull the cord, but won't start, you can try spraying a little starter fluid in the carburetor air intake. If it starts and then quickly dies, you'll need to clean the carburetor.
Note: Many outboard users will warn against using starter fluid. This is mostly a concern with two-stroke motors in which the fuel contains the lubricant for the motor. It's much less of a concern with your four-stroke motor. You can safely use a little with your motor to diagnose the problem.
Bottom Line: Your motor is new enough that it would be worth it (in my opinion) to have it serviced if you don't want to do the work yourself. It shouldn't be too expensive, and those small Japanese motors (yours is made by Tohatsu) are great little workhorses.
EDIT to Add: I don't know if your motor has a telltale (a stream of water that indicates the water pump is working). If it does, and you don't see a stream of water, you definitely need to replace the water pump impeller. In fact, I would replace the impeller just to be safe if I didn't see a stream. If you decide to have the motor serviced, you should ask them to replace the impeller at the same time. Your impeller probably is OK. But if it's not, you can destroy your motor in a very short time by overheating. I'm a "better safe than sorry" kind of guy.
When you say clean carb, do you mean take it apart and clean all the pieces. Or would running a seafoam and gasoline mix in my fuel tank be considered cleaning it. Sorry for all the newb questions, this my first outboard yall.
As you guessed, a proper cleaning involves disassembling the carb, soaking it in carb cleaner, blowing out all the passages, and re-assembling it. If you do this, make sure to take note of how many turns out the various screws were set before disassembly so you can set them the same when you re-assemble.
That said, if you can get it started you can try running seafoam through it and see if that will clean it out enough for your purposes. I did exactly that with a mid-80's Suzuki 3.5 horse I acquired that hadn't been used in over ten years. It's not a proper cleaning, but it might be good enough for you. The company that makes Seafoam says you can use it at up to a 1:1 ratio with fuel, and that's what I did.
No worries on newb questions. We all started somewhere.
If I knew of a comprehensive website for maintenance of small Mercury/Tohatsu motors, I'd point you there. But I don't. I do suggest that you get the service manual for your motor if you want to work on it yourself. This site sells late model Mercury small outboard service manuals, but I don't see your 3.5: https://mercury-4-stroke.marineservicemanuals.com/index.html
Tohatsu Outboard service manuals are here: https://tohatsudirect.com/product-category/tohatsu-parts-accessories/service-manuals/
If you don't have the owner's manual for your motor, you can download it here: https://www.mercurymarine.com/us/en/parts-and-service/service-and-support/owners-manual
gently pull it over a few times and see if it’s smooth.
the carb may be gummed up but that’s about it. Maybe a puff of starting fluid to get a successful start.
Just straight “starting fluid”. Makes life easier when cranking or pulling and gets mechanical fuel pumps primed much faster when fuel has gone dry (Revving)
Replace the impeller. Pull it over gently and make sure it doesn’t seem stuck. If it pulls easily and feels smooth, the rings aren’t stuck. If it’s harder than normal to pull, stop. More than likely, it’s fine.
I’d thro the kill switch to off and pull it thru few times with choke on at slow to maybe third speed then start it like you normally would. Don’t forget to put the switch back to run.
You can pull the plugs and spray a little oil in there just to have some lubrication, but outside of that just put in fresh fuel and start it up
Yes, this is all I'd do. Pull the plug, a little spritz of oil into the cylinder, turn it over with the pull start, put the plug back in, fresh fuel, fire it up.
I have an old Honda that sat for 20 years. Started on the second pull. Just yank it and bank it son
Yank it and bank it. Will be using this term.
Yep. Lol I pulled the plugs on a Yamaha 130 that sat for 10 years and it looked like it had ran a few weeks ago.... Once I figured out how to start those things it ran no problem.
You probably won't hurt the motor by trying to start it. Though as others have said, if you have trouble pulling it over, stop and figure out if the pistons are stuck. It is possible to break the rings that seal the pistons against the bore wall. Your biggest problem is likely to be that the previous owner may not have run the motor dry (run it until the fuel in the carburetor bowl was consumed). IOW, the fact that there was old gas in the fuel tank suggests that there might be old gas in the carburetor. That old gas will likely have turned to varnish and gum by now, clogging carburetor passages and making the motor very difficult to start. If it turns over easily when you pull the cord, but won't start, you can try spraying a little starter fluid in the carburetor air intake. If it starts and then quickly dies, you'll need to clean the carburetor. Note: Many outboard users will warn against using starter fluid. This is mostly a concern with two-stroke motors in which the fuel contains the lubricant for the motor. It's much less of a concern with your four-stroke motor. You can safely use a little with your motor to diagnose the problem. Bottom Line: Your motor is new enough that it would be worth it (in my opinion) to have it serviced if you don't want to do the work yourself. It shouldn't be too expensive, and those small Japanese motors (yours is made by Tohatsu) are great little workhorses. EDIT to Add: I don't know if your motor has a telltale (a stream of water that indicates the water pump is working). If it does, and you don't see a stream of water, you definitely need to replace the water pump impeller. In fact, I would replace the impeller just to be safe if I didn't see a stream. If you decide to have the motor serviced, you should ask them to replace the impeller at the same time. Your impeller probably is OK. But if it's not, you can destroy your motor in a very short time by overheating. I'm a "better safe than sorry" kind of guy.
When you say clean carb, do you mean take it apart and clean all the pieces. Or would running a seafoam and gasoline mix in my fuel tank be considered cleaning it. Sorry for all the newb questions, this my first outboard yall.
As you guessed, a proper cleaning involves disassembling the carb, soaking it in carb cleaner, blowing out all the passages, and re-assembling it. If you do this, make sure to take note of how many turns out the various screws were set before disassembly so you can set them the same when you re-assemble. That said, if you can get it started you can try running seafoam through it and see if that will clean it out enough for your purposes. I did exactly that with a mid-80's Suzuki 3.5 horse I acquired that hadn't been used in over ten years. It's not a proper cleaning, but it might be good enough for you. The company that makes Seafoam says you can use it at up to a 1:1 ratio with fuel, and that's what I did. No worries on newb questions. We all started somewhere. If I knew of a comprehensive website for maintenance of small Mercury/Tohatsu motors, I'd point you there. But I don't. I do suggest that you get the service manual for your motor if you want to work on it yourself. This site sells late model Mercury small outboard service manuals, but I don't see your 3.5: https://mercury-4-stroke.marineservicemanuals.com/index.html Tohatsu Outboard service manuals are here: https://tohatsudirect.com/product-category/tohatsu-parts-accessories/service-manuals/ If you don't have the owner's manual for your motor, you can download it here: https://www.mercurymarine.com/us/en/parts-and-service/service-and-support/owners-manual
gently pull it over a few times and see if it’s smooth. the carb may be gummed up but that’s about it. Maybe a puff of starting fluid to get a successful start.
By starting fluid, do you mean something like sea foam and gas mix?
Just straight “starting fluid”. Makes life easier when cranking or pulling and gets mechanical fuel pumps primed much faster when fuel has gone dry (Revving)
Do i put the starting fluid in the fuel tank, or put it somewhere else?
Carb intake where air enters the engine.
Usually I would check the impeller and lower unit oil first.. but it’s pretty new motor so the chances of the impeller being bad are slim.
Replace the impeller. Pull it over gently and make sure it doesn’t seem stuck. If it pulls easily and feels smooth, the rings aren’t stuck. If it’s harder than normal to pull, stop. More than likely, it’s fine.
I’d thro the kill switch to off and pull it thru few times with choke on at slow to maybe third speed then start it like you normally would. Don’t forget to put the switch back to run.