View Full Version : Power and speed

07-29-2019, 11:16 PM
I just purchased a 2008 Mercury 25 horse 4 stroke with three cylinders. The engine starts and seems to run fine idles great but feels like it only runs at full throttle around 3000 RPMs. (that's just a guess, there is no RPM guage). What could cause this? Improper throttle cable installation, a speed or RPM regulator? Any help would be greatly appreciated.

07-30-2019, 12:26 AM
Maybe the previous owner changed the prop because they had it on a small or lightweight boat. Can you check the numbers on the prop and report back to us?

07-30-2019, 02:00 AM
Get a tach first to confirm that.

07-30-2019, 08:52 PM
I sure will. Thank you. I know the prop has been changed. Any idea what the proper size and pitch should be?

07-31-2019, 07:30 PM
Probably a 9.75 X 9.5.