New '77 850 owner prop help needed

mprtech

Cadet
Joined
May 29, 2008
Messages
11
Hey guys, I just bought a used 77 merc 850. Not much history before the purchase but for 300 bucks I wasn't about to start complaining. Just checked compression and was happily supprised to see 140 130 140 140. After fogging and waiting 20 mins I tried to fire it up. Started great. Needs a starter solenoid, go figure but other than that it ran great. So far I have alot of Merc love.:)

The prop that came on the motor was destroyed. It was a 13x19p. My boat is a 1969 16' Starcraft alum, with 2 casting decks, full floor and 22 gal fuel cell. Its a heavy aluminum boat. The Evinrude 55 I have on it now will take the boat to 28mph with 2 people. The prop on the 55 is a 13 1/4 x 17.

The boat is used for fishing and tubing/skiing (hopefully with the added power)

My question is should I just buy a new 13x19p or should I do something different for the merc.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: New '77 850 owner prop help needed

Buy an aluminum 13x19 and that should put you in the ballpark. Without any RPM or speed numbers that's as close as we can get. What the boat did with the 55 is of no help. Different gearing, different power = different prop.
 
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