1978 Evinrude 115 hp #115899c

[ken_kaniff]

I ran over some trees in a local lake and it chipped my prop some. Now I'm looking to get another one. What prop should I buy? I like top speed props but have really wanted to start knee boarding. so I want one that will get a knee boarder out of the water.

 

[steelespike]

Re: 1978 Evinrude 115 hp #115899c

Please read the stickies at the top of rge page.
Your prop can probably be repaired at a prop shop.
We need your boat size and type,Present prop size(usually on the barrel or under the prop nut) need max rpm and speed.With this base line info we can help select a prop to suit your needs.

 

[ken_kaniff]

Re: 1978 Evinrude 115 hp #115899c

17 ft. deep v hull boat. prop says 13 3/8 x 17. max rpms 6000

 

[hwsiii]

Re: 1978 Evinrude 115 hp #115899c

How many RPM are you turning at WOT and at what speed and is the speed by GPS or speedometer. Year, manufacturer, length and model of your boat as well as make and model of your prop. And the year make and model of your motor as well as the gear ratio.

H

 

[ken_kaniff]

Re: 1978 Evinrude 115 hp #115899c

1978 Mark Twain deep v hull 17ft boat with evinrude 115 hp outboard. it runs at 5000-5200 rpms when I am going full blast. Before I hit the trees it would go about 39 mph, now goes about 35. i don't know how to find the gear ratio

 

[ken_kaniff]

Re: 1978 Evinrude 115 hp #115899c

and speed was checked by speedometer. is it really this hard to fit a prop to a boat?

 

[hwsiii]

Re: 1978 Evinrude 115 hp #115899c

If you want a good fit that runs in your maximum RPM range it does require a little bit of effort, yes

H

 

[hwsiii]

Re: 1978 Evinrude 115 hp #115899c

If you replace the prop you have now with one exactly like it or have that prop sent to the prop shop you will be right on the RPM you should be. You could change to a SS prop but your doing fine with what you have.

H

 

[ken_kaniff]

Re: 1978 Evinrude 115 hp #115899c

I would bet this prop is original. It is aluminum. 3 fin. I believe the 13 3/8 x 17 is the pitch correct? The closest I can come to the weight is on the plate. Says max weight is 1390 (including gear motor and persons) max persons load is 900 lbs. engine plate says rpms 4500-5500 standard 115 hp certified @ 5000 rpms.