Hi guys,
Got a 14' rib and re powered from a 25hp Evinrude 2 stroke to a Mercury 60 4 stroke
Old setup gave me 30 knots with just me on board
Now with over double the power I'm now barely managing to get to over 4000 revs and am running max 23knots
Load on the boat is
2 people aboard 120kgs (265lbs)
60 liters (16 US gallons) of fuel
engine plus boat is no more than 400kgs (882 lbs)
Prop is an 10"x12"pitch Solas - This should actually be an undersized prop
To add to all of this if I run for more that 5 mins at over 3000 revs I'm getting an alarm and the engine drops down to 2000 revs
Alarm stays on at 2000 revs
Water coming from the back is a steady stream and is not hot to touch
Engine is cool enough to touch
If I turn off ignition and restart the engine will allow WOT again
I tried a larger prop (11"x15"pitch) and the boat just slugged she barely wanted to plane
According to the manual I should actually pop in a 10"x16"pitch
So far have done the following
-made sure cable actually opens carbs to full throttle
-change fuel filter
-new plugs
-fresh gearcase oil
-fresh engine oil
any ideas as I'm now out... really hope I didn't buy myself a lemon :-(
regards
-J
Got a 14' rib and re powered from a 25hp Evinrude 2 stroke to a Mercury 60 4 stroke
Old setup gave me 30 knots with just me on board
Now with over double the power I'm now barely managing to get to over 4000 revs and am running max 23knots
Load on the boat is
2 people aboard 120kgs (265lbs)
60 liters (16 US gallons) of fuel
engine plus boat is no more than 400kgs (882 lbs)
Prop is an 10"x12"pitch Solas - This should actually be an undersized prop
To add to all of this if I run for more that 5 mins at over 3000 revs I'm getting an alarm and the engine drops down to 2000 revs
Alarm stays on at 2000 revs
Water coming from the back is a steady stream and is not hot to touch
Engine is cool enough to touch
If I turn off ignition and restart the engine will allow WOT again
I tried a larger prop (11"x15"pitch) and the boat just slugged she barely wanted to plane
According to the manual I should actually pop in a 10"x16"pitch
So far have done the following
-made sure cable actually opens carbs to full throttle
-change fuel filter
-new plugs
-fresh gearcase oil
-fresh engine oil
any ideas as I'm now out... really hope I didn't buy myself a lemon :-(
regards
-J