73 Johnson 65hp WOT sweet spot

[Sidserv]

Can anyone tell me what the WOT RPM is for a 1973 Johnson 65Hp is? I try to keep it in the 4500 to 5K range but the whole speed thing isn't a major concern for me. I am quite happy chugging along but I can't remember what the max RPM is anymore. I have the factory manual but I moved a couple months ago and I am really not sure where I put them when I unpacked.

 

[TN-25]

Re: 73 Johnson 65hp WOT sweet spot

It sounds like you are in the right territory. The factory recommended the full throttle operating range to be within the 4500-5500 RPM range for your 1973 65 horse motor. If your motor is overpropped and doesn't reach at least 4500 rpm then you are not reaching the rated power, and potentially you could be lugging the motor. Underpropping is fine if you tow water skiers, but the potential exists for over-revving the motor without the load it is propped for, plus you are giving up mph and fuel economy. Over-revving can destroy a motor in spectacular fashion. You are o.k.

 

[Sidserv]

Re: 73 Johnson 65hp WOT sweet spot

Thanks TN-25 for the info. You also gave me a good laugh. I don't know of anybody who runs a 39 year old motor for fuel economy.