69 Johnson 33hp won't push boat

[The Big "G"]

I recently bought an old Terry stick steer boat that has a 69 Johnson 33hp Seahorse. Motor idled and ran great in the barrel (which they all do when someone is selling). Took it to the lake yesterday and it won't push the boat, put it back on the trailer. The prop just spins, pin not sheared. Not sure if something needs adjusting on the shift cable or on the motor itself. Thought something was strange when I didn't hear the famous chunk putting it gear. Any ideas?

 

[lindy46]

Re: 69 Johnson 33hp won't push boat

So the motor revs up but boat just doesn't go anywhere? That would be the classical symptoms of a spun prop hub.

 

[F_R]

Re: 69 Johnson 33hp won't push boat

Did it pump water? If not, drive shaft might be broken. Otherwise check the prop hub. Do you know how? Make a mark on the prop nut and another mark on the prop, aligned with the first one. Run motor till the suspected slippage occurs, then stop it and check your marks. If no longer aligned, it slipped.

I still suspect mechanical damage though, based on what you said about no clunk. Maybe it isn't even shifting into gear. The shift rod may be disconnected or broken. Remove the oval plate from the side of the midsection and see if the rod moves up and down when you shift.

 

[The Big "G"]

Re: 69 Johnson 33hp won't push boat

Yes it pees when running and revs up good. i don't know anything about a boat motor but I think I am fixing to learn

 

[54bobby]

Re: 69 Johnson 33hp won't push boat

sort that problem out and you have a great little engine there.

 

[kfa4303]

Re: 69 Johnson 33hp won't push boat

Hi Big G. Welcome to iboats. Neat old "Big Twin" motor. I used to have a ;66 33hp myself. It should have more than enough power to move you along nicely. The fact that the motors "runs", but doesn't "go" makes it sound like there is an issue with the lower end, most likely the prop. There are a few tests you can perform to check. Start with the motor OFF and try putting it into/out of gear manually. Flip it into FWD then rotate the prop CLOCKWISE by hand. You should be able to get about 1/8 - 1/4 of a turn before you fell it catch. Once it does, it should be quite solid. Repeat the procedure after putting the motor in REV and rotating the prop Counter Clockwise until it catches. The prop should spin freely in in either direction while in neutral. If all of that checks out, you'll have to take the motor out on the water again to test for a spun propeller hub by scribing a horizontal line across all of the surfaces on the back of the prop. You then take the boat out on the water, bring it up to speed until the prop slips, then return to the dock and remove the prop. If the line is still level, then the hub is ok, if the line is broken, then the hub is indeed spun and you'll need to either have i re-hubbed, or a buy a new prop. Here are some handy links to help with all around maintenance. You can get any routine parts you may need right here at iboats.

Reviving a Vintage Big Twin - Part 1
1969 Evinrude 33953A 33 hp Outboard Motor Parts

 

[The Big "G"]

Re: 69 Johnson 33hp won't push boat

Thanks, Rear Admiral. That the best answer I've gotten and sounds easy to do

 

[The Big "G"]

Re: 69 Johnson 33hp won't push boat

Rear Admiral,

I guess the prop is the problem. In gear, the prop just spins on the hub of the prop. Thanks for your help

 

[kfa4303]

Re: 69 Johnson 33hp won't push boat

No problemo. You should be able to get it re-hubbed at a reputable prop shop, or you can get a replacement. You can find them on ebay, aomci.org, or you can buy a brand new one. It should make a world of difference. However, you may also want to check the shift shaft linkage located on the side of the exhaust leg to make sure it's connected properly. While the motor doesn't have the greatest high end performance it should have lots of low end torque. You'll have to do lots of trial and error to find the optimum trim/tilt set up. Most folks find the 2-3 position away from the transom works best. The anti-vent plate located just above the prop should also be level, or slightly higher than the keel.