I just purchased a used Johnson 70 Sea-Horse outboard motor. Is it a good motor? The engraving next to the SN is 70ESL75E. It is running with a little hesitancy starting. So I need to do my initial maintenance. I hope I am not repeating this topic posted elsewhere. I am brand new to boating on Lake Travis.

0. What year is this engine. I think my title is wrong.
1. Does the engine oil need changed with filter? What other fluids need changed?
2. What kind of 2-stroke oil do I mix in the gas and with what ratio (50:1 right?) ?
3. What type of spark plugs are best and what gap do I set.
4. How do I obtain a service manual, and are they worth it?
5. Should I bother with a new fuel filter if it is running?
6. What are common problems with this engine that I need to be alert for? Does the rubber hose crack, etc?
7. Anything else I need to do before "getting on it".

Your replies much appreciated, thank you.