Boat motor problem?

Question

I have a little 8hp Johnson motor. It will be running just fine for a while but then all of a sudden it will stop, it doesnt die, it keeps running, but it stops propelling the boat forward. It makes thursts forward like it wants to go, but it just doesnt. After a while of sitting there waiting for it to work again, it finally thurst forward and work. Whats wrong with it?

Answer 1

Hello--

You definitely have what is called a "slipped hub" on your drive unit.  I'm not sure if you have spline drive (slips in protection of your gearcase) or a pin drive (shears the pin in protection of your gearcase).  Either way, you may find rubber filings inside of the hub, which is a dead giveaway as to what is happening.  Depending on the age, and type of propeller, they might can rebuild your current prop or you may have to obtain a new prop, such as a Michigan Wheel replacement.  If it were mine, I'd opt for the latter.  Hope this helps...

JHW

TX

Answer 2

Look at how the prop connects to the motor . If the engine is running fine it sounds like the drive is slipping . On larger engines there is a rubber in the prop outside  the the drive splines and this wears , causing the prop to slip . Not sure what yours has . May be a split pin set up . If so pull it out and check for breakage or wear .

Answer 3

Take the prop off and check for broken pin. Pin ok? Have lower unit checked.

Answer 4

Make sure the breather on the tank isnt blocked