Need help with propeller

[imported_alex_G]

Hello all,

I have OMC 800 1985 5.0L engine.
I need to replace propeller but I can't find any information.
When I got this boat 14 1/2 X 19 3 blade prop was installed and also one more smaller size was included. I came across of an add about 4 blade prop. They claim that it's better than 3 blade. Is it true? What would be the right size prop for my boat?

Thanks

Alex

 

[achris]

Re: Need help with propeller

3 blades or 4 blades depends on what you're using the boat for... I found the 4 blade to be a lot smoother, but gave me too much bow lift...

The right prop is the one that allows the engine to run in the recommended rev range, as specified by the manufacturer, at Wide Open Throttle.

Chris...................

 

[imported_alex_G]

Re: Need help with propeller

That's the problem - I can't find recommended size in my manual

 

[achris]

Re: Need help with propeller

There is no recommended size... It's all done by the revs at WOT.... I think for the 5.0 litre you should be pulling about 4200-4600rpm at WOT...

Chris........

 

[HT32BSX115]

Re: Need help with propeller

This should probably be moved to the PROP section you might get more attention there....

 

[steelespike]

Re: Need help with propeller

Start by getting us your present prop size and the max rpm and speed.
also the size and ype of boat.Actual prop would depend on these specs and your typical load and activities.

 

[imported_alex_G]

Re: Need help with propeller

my current propeller is 14 1/2 X 19
I'm getting 35 mph on 3500 rpm.
according to manual max cruise rpm is 3400-3600 / max rpm 4200-4600