Hi guys
I have 1991 Larson All American 170 with 4.3 Mercruiser AlphaOne 190HP
I have 14.5 x 19pitch prop. When running WOT test, I max out at about 42mph and tachometer is showing 6000 rpm but it should be between 4400 and 48000.
At first I was thinking I might need to try a different size prop pitch but we are thinking my tachometer might be out of whack, the arrow goes up and down when idle (the engine is running solid good). Also, when just starting to take off the RPM looks to high to be true, between 1000 and 3000.
What is the best/cheapest way to check to make sure my tachometer is working fine...i read that there are some portable/handheld tachometers, are those any good? Any recommendations?
I have 1991 Larson All American 170 with 4.3 Mercruiser AlphaOne 190HP
I have 14.5 x 19pitch prop. When running WOT test, I max out at about 42mph and tachometer is showing 6000 rpm but it should be between 4400 and 48000.
At first I was thinking I might need to try a different size prop pitch but we are thinking my tachometer might be out of whack, the arrow goes up and down when idle (the engine is running solid good). Also, when just starting to take off the RPM looks to high to be true, between 1000 and 3000.
What is the best/cheapest way to check to make sure my tachometer is working fine...i read that there are some portable/handheld tachometers, are those any good? Any recommendations?
