How do I know when I need to refill the power trim?

[ZmOz]

I have a '74 Mercury 150hp inline 6 outboard with power trim. When I bought it (about 3 weeks ago) the previous owner gave me a bottle of oil and said sometimes you need to top off the power trim. How do I know when I need to do this? Is there somewhere to check the level of the oil or something?

 

[Blueboater]

Re: How do I know when I need to refill the power trim?

As far as I know just take out the fill screw and look into it, if it is low add oil and reinstall the screw, if full then just check later.<br /><br />Also what kind of oil did the owner give you, what does it say on the label of the bottle?