Strut alignment

Measure the gap between the shaft and the cutlass bearing all of the way around the shaft and on the front of the strut and rear of the strut. If you see a larger gap at the top of the cutlass bearing on the fwd side, and a larger gap at the bottom of the rear side, the strut would be angled slightly and not aligned......

Done properly, a yard will laser-target your drivelines as well as check the shafts with a dial indicator.

When dealing in thousands of an inch sort of measurements, I would not recommend using natural sight in measuring, you need the right tools.
If your struts are out of line which sounds very possible, you do not move the strut to fix it. You have to align the bearing properly within the strut. I have seen where they have enlarged the strut bearing housing and then chalk fast the bearing back in properly. The vessel gained much needed power and got on plane much faster. It certainly takes some experience for that sort of work to do it right.

Step one.

Unbolt the shaft coupling from the engine. If it is alinged properly the shaft will turn with little resistance.
The factory replaced a strut for me receintly after I hit a submerged something that distroyed two props and severly bent one shaft. I was the helper for this emergency repair. The mechanic loosely bolted the strut to the hull and using the jack bolts in the strut base, made fine adjustments until the shaft, without the prop on spun easly by hand. We carefully snugged the strut bolts checking for ease of rotation, then he mixed some epoxy to fill the gap in between the strut and the hull. She runs smooooooth now.

PS: He realigned the engine after the strut work was complete.

Hi,

I think he means that the bore for the bearing housing ( the hole in the strut)is increased in size to allow the bearing to be installed up or down at one end by the use of jacking screws/bolts and then the whole lot is set in place with Chockfast Orange.

ITW Chockfast Marine | Epoxy Grouts, Adhesives, Repair Products, Coatings

This is a very common practice in the big boat field so don't see why it wouldn't work just the same on a smaller shaft line.

Chockfast Orange

Sorry but I don't know. All I can tell you is he installed the epoxy around six PM and I went back in the water the next morning.

Yes K1 said it precisely. On the larger yachts the strut is usually rigid mounted and not ideal to tamper with, so the bearing is chocked-fasted in straight with the jack bolts. Of course this will not be the same route for every vessel with strut alignment issues.

When I worked for Viking as a mechanic we had replaced some 60 boats' struts with new ones. We removed the old strut and filled in the retaining hardware holes. To place the new strut in the proper location a tight wire was strung between the engine room transmission/gear and the back of the bottom new strut (on larger hulls there was an intermediate strut) which was held in place by a special jack. On the wire was discs which were fit to the shaft size. When the discs were able to be inserted into the strut with little effort they were then centered and strut was in the proper place. The strut base which mated to the boats hull was coated with wax and filler was put on top (to the hull and strut) after finding the proper location and holes were drilled for the securing hardware. Then the strut was dropped, wax removed and placed back into position so that the bolt hardware installed and the discs still were centered. There may be a few details I've left out but we never enlarged the strut to accommodate moving the cutless bearing around. We did not use a lazer as some do- it's easy to fool the lazer with jack stand adjustments and the disc/wire method was more than accurate with proven results time and time again. I also worked for Liberty Yachts and set and installed several hulls with struts and engine placements with this method.

target wire....

Are you sure the bolts aren't countersunk in the strut and painted over? I've never seen a strut that wasn't bolted on with either a flat head machine screw/bolt or a carriage bolt. Scrape the paint off and check in good light. I would take all of the packing out and check the shaft for wear in that area before I started dropping struts if you are concerned about the turning resistance.

You can also get some new clearance fit bearings and with the shafts chocked you should be able to slide the new bearings into the bearing carriers and spin them by hand, with only 10 thou clearance (on 2.5" shaft) everything needs to be lined up pretty well to achieve this.