trolling & speed

alamos · 29 July 2012, 17:05

I have a 1990 mariner 9.9 which has 3 pre-set tilt stops and 3 further manual tilt positions for 'trolling'. The engine is on a 3.2m air deck honwave. Can anyone advise if 'trolling' is up to a certain speed? - If I'm just pottering on the river at say 4 knots, which position do you think would be best? - Thanks - Andrew

lightning · 29 July 2012, 17:42

The anti-cavitation plate at the bottom of the engine leg, above the prop should be parallel with the water so whatever trim position achieves that will be the one to go for.

This applies whether trolling or at speed.

Although it matters less at trolling speed.

alamos · 29 July 2012, 17:52

Thanks for that - I guess I'd do better to try & line it up by eye then when the boat is out of the water?

lightning · 29 July 2012, 18:20

You can do that, or line it up as best you can see when the boat is in the water.

At trolling speed it won't matter so much. When you get up to speed you could try it in +1 or -1 trim positions from the one you selected, and see what works best on your boat.

alamos · 29 July 2012, 19:01

Thanks lightning - I've just inflated it, fitted the engine & levelled the whole thing on the lawn. Position #2 is just about parallel to the water line so I'll leave it on that one for the moment. One of the problems with changing down a notch with the mariner is it needs to be in forward gear to do it and you have to tilt the engine right up before you can come back down - not something I fancy doing whilst standing up in a moving boat!