1972 Mercury 800 80 Hp

[kjburr08]

Looking to get a new prop and I have never bought one before. Heres the link for the types I can get
http://boatpropellers.iboats.com/Me...s/290/?**********=924841453&*******=246425553
I am wanting to get a prop that is good on the lower unit and also where the rubber hub is unbreakable.

What are your guys recommendations?

 

[Bondo]

Re: 1972 Mercury 800 80 Hp

What are your guys recommendations?

Ayuh,.... You've gotta answer these Questions first,...."Read This First"

 

[hwsiii]

Re: 1972 Mercury 800 80 Hp

KJ, that link doesn't get us to where you intended, but you certainly don't want a prop with a rubber hub that won't break loose under impact. If an impact with something doesn't break the hub loose all that energy is transferred directly to the shaft on your drive and most probably will either bend or break something at high RPM.

H

 

[steelespike]

Re: 1972 Mercury 800 80 Hp

If your thinking of a new prop its time to evaluate your present application.If you give us your present prop size,max rpm and speed we can tell if you can improve things.You may be able to fine tune your setup and gain some performance at no cost.

 

[kjburr08]

Re: 1972 Mercury 800 80 Hp

Well on the side of the prop it has 17P A3, and on the inner hub it has 48 53900-17. As for the rpm at max load I am unsure. Is there a way to find this out, or will I need a manual? My current prop is aluminum. My boat it and older yarcraft about 197?. Its a 14ft boat. Performance issue is that the prop is spun, need a new prop, or new hub? Rather buy a new prop if I can get better performance though.

 

[hwsiii]

Re: 1972 Mercury 800 80 Hp

With an allup boat weight of 1,500 pounds I show you will need a 19" pitch prop and run about 40 MPH if your gear ratio is 2.3 to 1 as I show. If the gear ratio is wrong then my numbers are wrong.

H

 

[steelespike]

Re: 1972 Mercury 800 80 Hp

We need the max rpm and speed with a light load is ok.You could get the hub fixed and test for the baseline numbers. then make a decision on a prop.
Where is the antiventplate (just above the prop)in relation to the bottom.
Even with the bottom is considered a starting point.

 

[kjburr08]

Re: 1972 Mercury 800 80 Hp

I am just kind of interested in getting it running, as I have not been able to use this motor at all really, so I know very little about it. How can I figure out the max rpms and max speed? Never really had a chance to use it.