Mercruiser engines must be properly aligned or the Drive Coupler will be damaged.
The drive is attached to the engine through the use of a drive coupler. This coupler is bolted to the engines flywheel or crankshaft. The male splined driveshaft yoke from the outdrive slides into the female splines of the drive coupler. The position of the engine must be just right to allow the shaft to fit the coupler properly.
Proper alignment is achieved by adjusting the motor mounts.
The mounts allow the engine to be lowered or raised.
The position of the engine tends to change with time.
Stringers settle and mounts get soft and sag.
If the motor drops out of alignment damage can occur to the drive coupler.
When a coupler fails, the boat will have little or no propulsion.
Replacing a bad coupler requires removal of the drive and engine.
Coupler failure can be reduced or eliminated by checking and adjusting the engine alignment on a regular basis.
Checking the alignment requires removal of the sterndrive unit.
A special Alignment Tool is slid into the drive coupler from behind and the tool must insert and turn easily. If the tool is too tight or can not be easily fully inserted into the coupler splines, the engine mounts must be adjusted until it will.
The alignment must be checked with the engine rotated in 90 degree increments. This is to insure that the coupler is "true" and won't wobble.
It is standard policy to check the engine alignment whenever the drive is removed.
The drive should be removed at least once each season to allow for an inspection of the gimbal bearing, bellows, shift cable and alignment. It also provides an opportunity to properly grease the driveshaft yoke splines and cross bearings.
Click HERE for new Drive Couplers.
