1966 Evinrude Ski Twin: Two or three questions.

[Hillbillywill]

Just when I think I have it all put together.

1966 Evinrude 33 hp ski twin on a 1964 Crestliner Mustang (fiberglass). Motor runs like a champ (116/116) with recent tune up, new points/impeller, but on initial sea trials the stern would not get out of the water and boat would not get up on plane. it pushed a huge wake, but top speed was about 10 mph. it was like a barge and not a runabout.

I did some research and see that the cavitation plate on my boat was way below the keel, so i lifted the motor using a block so that the cavitation plate is just below the keel. I thought about changing the prop so i pulled it off. The current prop is 10.5 x 13 (going from memory). I noticed that there was no keyway or woodruff key on the prop shaft. just the pin and prop nut.

does anyone know if they key is imperative? what size key i would need? and does do you think that raising my motor will hopefully resolve the poor performance. and should i consider changing props with a different pitch.


thanks.

i'm a novice rookie learning the hard way.

 

[82rude]

Re: 1966 Evinrude Ski Twin: Two or three questions.

theres no key so to speak,just your shearpin and of course the locking nut.can you take pic of boat and motor from the back particularry?raising the motor will definately help as long as its done correctly and safely.as for the prop pitch you need a tac or your only quessing.i dont have my book in front of me so mabe somebody else can chime in with the wot.range.

 

[boobie]

Re: 1966 Evinrude Ski Twin: Two or three questions.

Is it running on both cyl's ?? Do a cyl drop test on it.

 

[kfa4303]

Re: 1966 Evinrude Ski Twin: Two or three questions.

+1. I think you may only be running on one cylinder. I used to have a '66 33hp and it has plenty of power and should easily push a 14'-16' boat along in the mid-high 20mph. To test the spark, remove the spark plug leads one at a time using insulated pliers. The motor should run/idle on one cylinder. If/when it dies completely when you disconnect the spark plug lead, then you know there is an issue with the ignition. Thankfully, you can rebuild the entire ignition yourself for about $60-$70 often times less than that. Here is a great link that can walk you through a tune up from top to bottom. You can get any routine parts you may need right here at iboats.

Reviving a Vintage Big Twin - Part 1
3 HP Evinrude Lightwin Ignition System Tune-Up 1952-1967 (great ignition rebuild link. It's for a different model, but all of the steps are the same)
1966 Johnson RXE-14 33 hp Outboard Motor Parts