Frequently Asked Questions


Engine Alignment I/O...

How do I align my Inboard/Outboard Engine?

Proper engine alignment is a crucial part of extending engine coupler life. Periodic inspection of the engine and outdrive should be done at least once a year and after each engine or drive R & R.

Most outdrives are coupled to the engine via an "engine coupler". This is an internally splined receptacle mounted in a rubber hub that aids in protecting the engine from outdrive impact and vibration. The coupler bolts to the flywheel and accepts the outdrive "Yoke Assembly". It is very important that these two items are centered exactly on the engine crankshaft center line (fig. 1). This will insure that there isn't any excessive force being applied in a lateral direction causing premature wearing of the coupler splines, yoke assembly splines or the coupler.

Proper alignment can be achieved with the use of an "Alignment Tool" using the following guidelines:

Insert the tiered end into the gimbal bearing and move the tool to center with the engine coupler splines. If the tool enters the coupler freely and is fully seated in the coupler without any pressure (fig 2.), the engine is properly aligned.

If this is not the case, remove the tool and coat the end with a small amount of grease. Carefully reinsert the tool and fully seat the tool in the coupler. "Careful - Do Not Rotate Tool Upon Installation Or Removal". Remove the tool and inspect the greased end.

The following should be noted:

A: Deep groves on top of tool and shallow groves on bottom, then FRONT of engine is too HIGH.
B: Shallow groves on top of tool and Deep groves on bottom, then FRONT of engine is too LOW.

In either case the front of the engine must be adjusted up or down to allow the tool to slide freely into the coupler.
Loosen lock tabs and nuts on front mount(s). Thread all adjustment nut(s) equally. This will help prevent "cocking" the front of the engine. After proper alignment is achieved, tighten all nut and replace locking tabs.

If alignment can not be achieved, check for:

Worn or bad mounts
Rotten stringers
Bad or weak transom

Reinstall the outdrive by coating the yoke assembly with grease and using the proper gasket set. Torque all nut and bolt to factory specs and your customer should receive years of boating pleasure.

figure 1 figure 2