Trim Limit Switch

diaboy5681

Cadet
Joined
Sep 1, 2006
Messages
11
Hey guys, just turned 20 and about 4 weeks ago bout an 89 sea nymph ss 175 fish n ski with an 89 rude spl. It has power trim/tilt so this got inspired by the other post, how do I find out if my boat has a trim limit switch and better yet if it is working or not? I would hate to find out the hard way, I have been scared to trim it while im crusing just for that reason. Thanks in advance.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Trim Limit Switch

the 89 spl motors had no trim limit switch, the trim"limiting" was done with the up relief valving. above about 2000 rpm or so the downward thrust of the prop will force the valve open and disallow hydraulic presure to the tilt ram.
you will have cavitated long before you hit the top of the trim pins.
takes some practice to get used to power trim and trim guages are mostly usless.
I suggest reading the owners manual or better have an experienced helmsman show you. not all trim positions are best for all speeds,loads and seastates.
usually to accelerate from a standing start the motor needs to be in the full down position then trim the bow up as needed for the best ride and planing speed.
remember the stern controls a boat not the bow.
if the stern is to high(to much trim down) the bow may try to steer the boat with potentially disasterous results, stern to low(engine trim to high) and prop ventilation will occur with potentially disasterous results.
you will find high speed cornering will ususally require trimming down and back up after the curve or prop ventilation and loss of stern control will result normally.
the whole key to controling a boat is controlling the stern, if you cannot your out of control.
barring bow thrusters boats are 99% controled by moving the stern and forcing the hull to pivot on its axis.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Trim Limit Switch

Depends on which 89 SPL you have. A HP or model number would help. The seat of your pants will tell you if you are trimmed too high and your ear will tell you if you experience ventilation as the engine will begin to over rev as it loses bite.
 
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