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Need help with 1966 Johnson 20hp outboard

A

Anthony Massingill

New member
Real quick I just replaced my impeller and gear link now my motor will only push the boat at idle speed even at full throttle motor rpms just fine and sounds good. Thinking may have to adjust the linkage up or down what do you think
 
The grooves in the shift rods "must" be aligned perfectly with the bolt holes in the brass shift connector.
 
Yes it is hooked up. Before we took off the homemade link the motor ran fine just had to turn prop by hand a little to get it to go into gear, now it shifts fine forward and back but doesn't have the thrust behind the throttle will Rev up but still only go about 2mph if lucky going to adjust the link to see if that does anything.
 
So, you say it will move the boat 2 MPH. That tells you that it is going into gear. I say you have a spun prop hub. Just a coincidence that it picked right now to happen. To prove it, make a mark on the prop nut (or just use the cotter pin as a mark), and make another mark on the propeller. Run motor till suspected slippage occurs, then stop and check the marks. If they no longer align, the hub slipped. If they do align, repeat the test. There is a chance it stopped slipping in the same place.

If you find it is slipping, simply replace the prop.
 
What do you mean by homemade link?It could be the shift handle is out of adjustment keeping you from advancing the timing fully in forward gear. First is you must make sure both the upper and lower notches in the shif rods are center in the holes on the shift coupler in the window. Then make sure it is in neutral so the prop spins free. There are two screws that hold the shift lever to the horizontal shaft loosen both screws and move the handle so the detent for the shift lock is center of the middle notch in the shift lock lever and the handle should also be straight up and down. Tighten both screws on the handle and then spin the prop and shift into forward and reverse. The detent should seat firmly in both the upper and lower notch in the shift lock lever respective to the gear.
http://www.ebay.com/itm/Johnson-Evi...ash=item54294ab921:g:8XwAAOSw5dNWmm65&vxp=mtr
When not adjusted properly it will keep you from advancing the timing past high idle speed.
 
The vulcanized rubber between the bronze hub and the aluminum propeller has become faulty and a fair amount of slippage has resulted. The water pressure encountered by the propeller is just too great and is causing the propeller to become unable to turn the proper rpms, which in turn is allowing the lower units propshaft to turn the bronze hub much faster than the aluminum propeller that is normally fused to it.

The cure?...... Re-hub or replace the propeller. We know what we're talking about. Don't argue with us. :)
 
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