prop size for 1982 70hp evinrude help

[fishon13]

I'm looking for the prop size for a 1982 70hp evinrude. Model # j70elcnb, it's on a 15 fiberglass hull and I fish and pull my kids, fresh water. I'm looking jor the stock size and what size would be best for my application.

 

[steelespike]

Re: prop size for 1982 70hp evinrude help

Please read the stickies at the top of the page.
There isn't really a stock size it depends on the application.
If possible we need your present prop size,(usually on the barrel or under the nut),max rpm and speed ,light load.Also with your typical load if possible.
Boat brand,style weight ?

 

[fishon13]

Re: prop size for 1982 70hp evinrude help

can't get to the info right now. Droped the boat off for carb work, possible stuck float. when I get the boat back I will post back, up to a week and a half no fishing this weekend. thanks for the input The boat is a bass bomber load is around 800 pounds with hull motor weighs 264 pounds. general use is fishing. I have two kids 7 and 9 like to be pulled. so i need to plane fast. It seems to the ear to be running at about 4,500 rpm if that top speed about 35mph.

 

[steelespike]

Re: prop size for 1982 70hp evinrude help

We'll need your rpm by tach to do this right.You'll need the tach to be sure the prop selected is performing as it should,for the health of your motor.
If no tach a Tinytach is reasonable easy to install and will fit an 2 stroke motor with the number of cylinders as yours.