Lower unit question

[Waterfowlnut]

I have a 63' Johnson 18 hp that keeps wanting to slip out of reverse, I checked the shift link and everything seems right, I haven't opened up the gear box yet. But if the cog inside is worn, I have a 56' 15 hp Johnson with a lower that is fine, can I swap the two? Or would the 18 gear box be beafier than the 15. The 18 hp shifted fine before I changed the impeller, I can't understand why it keeps slipping.

 

[boobie]

Did you get the shift rod connector put back together correctly ??

 

[Waterfowlnut]

Pulled the one bolt, slid in the bottom half of the shaft, made sure the groove was lined up in the hole, insert and tighten bolt. Now when I put it in reverse it'll start clicking like crazy or kick right out of gear, unless I hold it gear.

 

[Waterfowlnut]

It actually doesn't really want to come out of forward, if I try to shift it into neutral, it'll stay in forward some of the time unless I play with the shift handle, I wonder if the yoke inside is worn out. I don't really want to pull the gearbox apart yet, I keep checking the fluid, there's no shavings or anything indicating gears grinding. I just wonder if the two lowers would be interchangeable, just to see if there a difference before I put an order in to marine engine for something that's still salvageable.

 

[bonz_d]

I would think that if it all worked as it should before the new pump was installed then something is out of position. Pull the lower unit back off and look over everything again.
I do believe the lowers are different between the old 15hp and the 18hp. but I could be wrong as I haven't worked with any old 15hp in a long time. I believe the 15hp shares the lower unit with the 10hp.

 

[Waterfowlnut]

Yup, upon rechecking the link it was too far in by about 3/16".

 

[bonz_d]

Good to hear you've got it sorted out!