Pontoon Boat & Deck Boat Forum

I have a 1998 Johnson 150 motor, does anybody know where I would be able to find what the RPM range is for this engine? Every chart I have found does not go prior to 2006 on the 150. Any help would be appreciated. Thank you.

I'd suspect between 5-6K....if you don't have a service manual, I'd suggest you get one...

[quote="JEB"]I have a 1998 Johnson 150 motor, does anybody know where I would be able to find what the RPM range is for this engine? Every chart I have found does not go prior to 2006 on the 150. Any help would be appreciated. Thank you.[/quote]

Most things I Googled --forums, iboats say WOT is 5500rpm with operating ranges between 4500-5500... Try to set it up depending on boat toward the upper limit of operating range. My 2009 90 hp Merc top end is 5800-5900---and if you hit it you get an alarm--not sure about the older motors. Good luck....

Usually running a motor at WOT and getting lower rpm's than what manufacturer states for motor is not good for motor. Major contributor is the prop.. Changing pitch of my prop by 1 inch on my pontoon boat makes a difference of around 350 rpms..

Again--raising or lowering engine on transom and changing props/pitches etc are the main things you can do to change boat performance.

Somewhere inside the engine cover, the rpm range is usually noted. 5800 is about normal on 2 strokes.

Those old 2 strokes pretty sure were 5500. Even the newest 2 strokes do best around 5600 to 5800.