1972 johnson 20 horse problem

[sjohnson]

HELP i bought a 20 horse 1972 johnson motor a week ago and it started to feel like i was hitting logs but i wasnt it seems like it is jumping out of gear or something it started doing it as i was first accelerating and only did it a couple times now it is much worse and had to idle 6 miles back up river. the motor it self runs great it must be gear linkage i do not know much about boat motors anybody have this happen any advice would be greatly appreciated thanks.

[marine_man]

A couple of things to check -

First, remove the prop and see if the shear pin is intact

Second, explain what you mean by hitting logs - the motor pushes the boat a little then rev's way up without moving much, or what?

marine_man

[sjohnson]

i just put a new prop on it took it off and pin was fine. the motor makes a big klunk noise like when you hit a log it does not rev high it goes in gear right away but it makes like gear jamming sound started doing it at lower and lower speeds thanks alot for reply.

[marine_man]

it sounds like lower unit problems to me then... I was hoping it might be a slipping hub, but if it's like you describe I think it's time for a trip to the dealer...

marine_man

[sjohnson]

that is what i feared thanks for the info

[Surface Tension]

I wonder if its not anything to do with the gears and maybe a lean sneeze.

[eurolarva]

Forward gear and clutch dogs are probably shot. After prolonged use and sometimes incorrect shifting the lead edges become rounded and they slip off of one another causing the feel of hitting a log. Lower unit will have to be taken apart. I have used a dremel on mine to re face them however I recommend having a machine shop do them. It is a lot cheaper then replacing them and when it is done they will be just like new.

[sjohnson]

thanks alot for the info much appreciated.