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AVickers
07-10-2000, 10:50 AM
Having had my new (to me) 22 out a few times, I now have a question about the steering. I was wondering if one of you Merc guys could help me...

The boat "pulls" slightly to the left (natural with a right-turning prop, but with power steering, I'm thinking that the steering should be neutral). I installed a vertical trim tab (initially it had only a disk) and set it to move the foot in the opposite direction (right) to counteract steady-state prop torque. However, even at it's fartherest range of travel, it only helps a little. The boat still pulls when you let go of the wheel -- not as badly -- but still, when you let go of the wheel, it'll gradually take off to the left, getting worse as it moves. I'm afraid to let the wife or kids drive the boat.

I remember someone saying there was an adjustment somewhere with the hydraulic system where you can "center" the spool valve so that the system is neutral when there's no input on the wheel.

My Merc book (as usual) is no help on the subject...

PaulO
07-10-2000, 01:19 PM
I can't help with the alleged adjustment but I will consult my shop manual. I can tell you though that my Merc with P/S and no tab will continue to go straight at any speed without steering input.
PaulO

AVickers
07-10-2000, 01:43 PM
Thanks,

The fact that yours goes straight with no input comfirms my memories of other Mercs I've driven, but it's been a while. All this leads me to believe there's something wrong w/ mine.

oldLenny
07-10-2000, 02:10 PM
I had a similar problem with my Bravo in a Chapparal. I got rid of it in two tries... First, I rotated the skeg in the direction I wanted to counter-steer the boat to over-ride the natural torque tendancy. This only made it worse. Then, I turned the skeg the other direction, the wrong way in my mind,steering the leg in the direction the boat was already having troubles pulling to. This fixed it so that it was hands off driving. Afterwards in thinking about it I realized you are actually using the passing water pressure to straighten out the lower unit. I assume you have done this but just wanted to pass this on to others who might not have...

AVickers
07-10-2000, 03:10 PM
On my non-power-assisted Volvo, I spent quite a bit of time figuring how to deal with torque steer and how much of it could be controlled with a vertical trim tab (or steering tab). When I got the boat, it didn't have a vertical tab at all and not only did she pull to one side like a bandit (in this case, to the right), she jumped all over after she was on plane and you accelerated or decelerated hard. The previous owner accepted this as pretty much standard for an "old Donzi." I agreed with part of that assessment, but did feel that things could be improved upon...

First I installed a vertical trim tab and got her to behave neutrally at steady-state rates of speed. As long as you didn't bump the throttle, you could take your hand off the wheel and she'd track straight and true. However, after she was up on plane, any time you changed the throttle, she'd hop right or left, depending on whether she was accelerating or decelerating...

Part of the problem turned out to be looseness in the steering components allowing the foot to move back and forth slightly -- depending on the momentum of the prop -- so she'd get ahead of me and any helm input. New pins and bushings tightenend everything up for something less than a day's work and $75 -- nine parts (three pins, five bushings and a seal).

The rest of the problem is that at about 3000 RPM the engine produces so much torque that she'll try to wrench the wheel right out of your hands -- the only thing standing between me and running around in tight circles would be my deathgrip on the wheel... The only thing between the helm and all that torque was that worn out, 100% feedback Teleflex cable steering system. To solve this, I installed zero-feedback Teleflex hydraulic steering setup.

Now, even my kids can drive her with no drama...

I'm now to the same point sorting out my 22 except the only problem I'm having is the steady state stuff -- it pulls to the left and even with a tab at full lock to the right. No drama when up and running: accelerate, decelerate, hop waves, anything and she's rock solid. Unfortunately, it pulls and I don't think that's right. Leads me to believe that there's something going on with the hydraulic system.


[This message has been edited by avickers (edited 07-10-2000).]