Will a 4 blade prop cause extra wear on an I/O

[yaj1976]

I have a 1989 omc cobra on my 20 foot four winns now rider with a 4.3 engine. I want to change to a 4 blade prop as I spend all my time on the ocean and use the boat for fishing. We are often in heavy currents and big waves. Top speed is not overly important. If I can still make 20 mph I would be fine. Currently I have a 3 blade 4 1/2 19 pitch. My main concern is during my research I've read the 4 blade prop will put extra stress on the internals of the outdrive. I would like some more opions on this before I make the change.

 

[steelespike]

A 4 blade can only put the strain from your 4.3 On the drive train.
Driven with a little care so as not to shift at too fast a speed/rpm.
Years ago there was a discussion about bronze props wearing on the drive train due to their weight
either the drive train has improved or the weight doesn't enter into wear and tear or ss props would be suspect.

 

[dingbat]

It takes X foot pounds of force to move your boat at X speed. Switching from a 3 blade to a 4 blade doesn't change that equation one bit. The only thing that changes is the efficiency of which available torque is transferred to the water. In automotive terms, a new clutch....

 

[yaj1976]

A 4 blade can only put the strain from your 4.3 On the drive train.
Driven with a little care so as not to shift at too fast a speed/rpm.
Years ago there was a discussion about bronze props wearing on the drive train due to their weight
either the drive train has improved or the weight doesn't enter into wear and tear or ss props would be suspect.

When you say put strain on the 4.3 drivetrain and you saying to the engine alone or the engine and outdrive. Thank you for the reply.

 

[jimmbo]

Just don't ease it into or out of gear

 

[Scott06]

I used two different pitch 4 blades on my '91 sea ray 170(3.0 IO). A 18" for general use, and 16" for skiing. Being underpowered this driveline spends most of its life above 4000 rpm taking the kids tubing and skiing, basically ran it like I stole it. Sure eventually this will shorten the life a 25 year old boat but absolutely no issues with the switch to 4 blade, what a difference in holeshot and bit in turns, you won't be unhappy with this switch.