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JEWIENEWIE
26-01-2007, 01:23 PM
I have a 4.2m runabout with a 30hp merc on the back. I dont know the tech name for it on the motor bracket there are a series of holes or slots that a pin goes through wchic will either raise or lower the normal running position of the motor. Sorry for the use if incorrect terms here. I believe that if i lower the position by moving the pin further back it will pull the bow down but move the pin uup, it will pull the bow up?
When i took delivery of the boat new, the pin was in the second slot closest to the transom, my question is would that have been set by the yard, would that be the best running position for my rig or how does it work, what should i be trying to achieve in boat performance when moving the pin. When i have her on the plane, the water spray seems to be coming of about halfway down from the bow where as when i see other boats on the plane, spray seems to be coming from around three quarters down from the bow. Can some one enlighten me a little please?
Jewie

finga
26-01-2007, 01:38 PM
Is your power trim/tilt??
There's no set place to put the pin and everybodies preferences are different to where they like the boat to ride.
If your happy with the performance and the acceleration of the boat and it doesn't porpoise (front raising and falling constantly whilst motoring pretty well) then leave it where it is.
If the boat is sluggish to get on the plane then go a hole out and if it porpoises go a hole in towards the transom.

Play with it to see what suits you best.
Your not going to break it by experimenting.
You'll be amased the difference a hole or two will make
Just don't drop the pin in the water when you experiment :(

It's all good fun experimenting :)

JEWIENEWIE
26-01-2007, 01:43 PM
Thanks finga, came very close to doing just that! i moved the pin out one hole the other day, she got up on the plane quicker, seemed to run a bit better but the steering didnt feel so sure?
Jewie

JEWIENEWIE
26-01-2007, 01:46 PM
Oh , its not power tilt or trim
jewie

Black_Rat
26-01-2007, 02:10 PM
Jewie,

I had a 4.2 with a 30hp and depending on the load I would often stop shorty after leaving the ramp to adjust the pin position. If you seem to be ploughing into chop with two on board with one up front having both people sitting at the stern will help the ride without having to adjust the pin position when traveling. If the motor feels light to steer at the plane in either direction than you would probably have the pin set to high and should drop it a position. I found that the best position was when the tiler arm was a little harder to swing to the left while driving with my left hand due to the tourqe of the motor. ;)