Yamaha 40hp unknown outboard ports

[captdiver]

I have an older 2 stroke 40 hp that has a couple of ports on the lower unit I'm not sure of what they are. I've had several O/Bs before, but other than the gear oil drain and check ports, I also have one labeled "Water" and the other one does not have a label. And ideas on these ports? Thanks.

 

[racerone]

Pictures needed.

 

[boscoe99]

Any idea what model motor? They are not all the same.

 

[captdiver]

https://photos.google.com/photo/AF1QipMImC391t2mW1fD8PKbx3e7whV7YK388MU2r00G

 

[racerone]

I see an oil drain / fill screw location.----I see oil vent screw.----And perhaps you should not touch that screw near the front of the gearcase.-----Changing the oil on an outboard is easy , but novices have made expensive mistakes in the past.

 

[captdiver]

Any idea what model motor? They are not all the same.

 

[captdiver]

I see an oil drain / fill screw location.----I see oil vent screw.----And perhaps you should not touch that screw near the front of the gearcase.-----Changing the oil on an outboard is easy , but novices have made expensive mistakes in the past.

Yes, I have changed the oil in many outboards. This was just the first time I have ever seen that screw at the front of the gearcase.

 

[boscoe99]

The one labeled wash is to flush the motor using a Yamaha flush hose in lieu of flush muffs.

The forward one is a mystery to me. I would remove the plug and see what comes out.

 

[racerone]

edited

 

[roscoe]

DO NOT remove the front screw.

The screw holds the shift cam assembly in place.

 

[boscoe99]

DO NOT remove the front screw.

The screw holds the shift cam assembly in place.

Interesting. Not shown or mentioned in the service manual.

 

[racerone]

From the parts book it appears to be a special bolt.----Makes sense that it prevents shift cam from being pulled up too far.----See post #5.

 

[boscoe99]

The mysterious screw is connected to the shift cam assembly. Confirmed by looking at a later service manual.