1971 merc 115

[Shawnb23]

Couple questions on my merc. I'm going to change my lower unit oil, A boat mechanic told me that 80-90w gear oil is just the same as using any other lower unit oil. Is this true, because I have alot of 80-90 laying around that need's used. Also on my control box on my boat. I have the old mercury one with the little lever on the side and the big lever that engages the gear. How should this work? Does the big lever just engage the gear and the little lever controls the throttle?

 

[AMD Rules]

Re: 1971 merc 115

Suggestion would be to use marine gear ol if you can, but if you're willing to change the oil each season you can probably get by with any 90 weight oil.

The small lever is to control the throttle, only for starting purposes. It allows you to raise the rpm without having to shift in gear. Once it warms up, you need to lower this small arm back down to idle. Motor should idle below 1000rpm, preferably around 750 to 800 in the water. The large arm shifts into gear, then advances the throttle for normal use. The rubber button if you have it is to choke, or you will have a push-in style key to choke the motor for starting.