Looking for a prop change

[Ben Fletcher]

I just bought my first boat. A 1989 Larson Laser DC-200. It's a 20 ft open bow v-hull fiberglass. It came with a 5 blade stainless steel ski/tubing prop and my kiddos are to little to do those things. So I am looking for insight on what I should get for an aluminum prop geared toward cruising and fuel economy. Boat has a Mercruiser Alpha One 5.7 liter. Left hand motor rotation. WOT 4200-4600 rpm. 260 HP. any help would be great! Thank you.

 

[QBhoy]

Hi there.
Befire anyone else chips in, you will likely need to advise on the gear ratio. Also a more exact wot rpm and gps speed with current prop and pitch.
I would also ask if you are sure it’s a left hand rotation. Quite unusual on a single engine drive.
Look forward to hearing more.

 

[QBhoy]

If it helps, it most likely it’s a 1.47 ratio as standard and should be a 19” 3 blade standard. Just that the left hand rotation might suggest it has been messed with ?

 

[Ben Fletcher]

I went out to my garage and checked again on the info I shared. I'm getting the motor information from a plaque on top of the engine. Let me type it again and see if I sent something wrong last time.
Mercury Marine MCM 5.7 Litre
Displacement- 350 CI
Horsepower-260
Engine Rotation- Left Hand
Max WOT RPM- 4200-4600

 

[QBhoy]

Ah. Perhaps engine rotation is left hand, but prop rotation right hand. I thought you meant the prop rotation was left hand.

 

[blamtro]

This may help you. I have a similar size boat with similar power package.

I was really happy with the mi wheel 4 blade I ended up with.

https://forums.iboats.com/forum/gen.../10239928-3-to-4-blade-prop-81-searay-srv-207

 

[Bondo]

I just bought my first boat. A 1989 Larson Laser DC-200. It's a 20 ft open bow v-hull fiberglass. It came with a 5 blade stainless steel ski/tubing prop and my kiddos are to little to do those things. So I am looking for insight on what I should get for an aluminum prop geared toward cruising and fuel economy. Boat has a Mercruiser Alpha One 5.7 liter. Left hand motor rotation. WOT 4200-4600 rpm. 260 HP. any help would be great! Thank you.

Ayuh,...... Welcome Aboard,..... To give ya a proper reply, We need some more numbers from ya,.....

What is the pitch stamped into the prop on there,.....
When you went Wide Open Throttle, how high did the Rpms get to,..??
Were ya trimmed out, 'n Flyin' at that point,..??