Re: Boat doesn't steer staight at no wake speed
Wandering off course at idle or slow speeds seems normal for the Mercury power steering assembly. It?s usually only noticeable at lower speeds when trying to steer a straight line, ending in chasing the course back and forth. The play is noted at the wheel and could be as much 3 or 4 inches. It's less noticeable in a deep 'V' hull design.
I've investigated this course wandering problem on Mercury I/O . There are various causes, none of them difficult to determine and correct, except ONE.
The cable may be worn and jammed inside the outer casing. see other posts for instructions of how to remove and grease or replace.
The gimbals can be worn in the housing rudder steering unit. See other posts for tightening gimbal bolts and adjustments inside the bellow housing by cutting access holes or engine removal.
It can be the steering head (Wheel gear worn or cable wear, resulting in poor engagement in the cable spiral or if another type, not pull/pushing the cable accurately). WITH THE ENGINE SWITCHED OFF. Determine this problem by disconnecting the cable from the power steering unit on the starboard side rear of the engine and having a helper rock the wheel left and right within the range of 'slop' whilst feeling the amount of movement on the inner cable. There should be no delay or slop, each small movement of the wheel should move the cable in and out by the same amount. If there's more movement at the wheel than at the cable end, its a cable or steering head problem. Replace one or both.
If the above check out ok, the problem is in the power steering. The steering cable connects to this on the starboard side rear of the engine. The steering rod mechanism terminates on the port side of the unit . Turning the wheel a half turn left and right will easily identify this rod. It can be seen or identified by touch as it moves in and out. If restricting the wheel movement to within the range of 'slop' and the rod does not move, the problem lies in the power steering unit. THERES NO FIX FOR THIS !
Unfortunately it seems to be a bad design, due to sliding of the spool valve to redirect the fluid left or right to assist the steering. Once the vessel is on the plane, the side thrust of the prop loads it up, thus overriding the play.
It?s plainly bad design but CAN THIS BE CORRECTED MR MERCURY_ OR MUST BUYERS BEWARE AND Think again next time when buying a Mercury sterndrive?
MR MERCURY . TECHNICAL DEPT WONT ATTEMPT TO ANSWER. INDICATING THEY WONT ADMIT THEIR DESIGN ERROR.
