1984 E30+ Strut Replacement Part 4
by, 03-09-2017 at 09:18 PM (238 Views)
I was finally able to put in a full day of work on the boat today. As shown in the last strut replacement blog, I started out thinking I would prop up the shaft on a barrel and some wood. I quickly realized this would cause the strut to move when I stepped on and off the boat (and with the wind shaking it around today). So I devised a framework that I strapped to the boat to hold the prop shaft adjustment jig in place. It was raining cats and dogs today, and I was bedeviled by drips. I was able to stop most of them with tape, but the strap wicked water right into the work area. I finally put some paper towels around the strap and this diverted the water right off the boat. Problem solved.
I purchased some polyethylene spacers from McMaster-Carr. The prop shaft is 1" and the ID of the shaft log is 1.26". The spacers were 1.25", leaving me with 0.01" of play. The back of the shaft drops this little bit and binds on the back end of the log due to the unsupported weight outside of the boat (before the strut is in place). The front spacer fit a little tighter than the rear one, so I did not need to support the front of the shaft inside the boat.
To get the prop shaft truly centered, I created an adjustment jig and attached it to the framework strapped to the hull. The shaft was supported by a bearing attached to a piece of 2x4. Some threaded rods run up to the upper cross piece. The upper piece has holes that are drilled oversized to provide plenty of adjustment range. Once the shaft was centered in the shaft log, I tightened up this jig to hold it in place.
Once the prop shaft was aligned, I went inside the boat and hot glued some cross pieces into place above the strut, again with oversized holes. Four long bolts were screwed into the top of the strut (I first put some mold release compound on the ends). When the nuts were tightened against the washer, the strut could be adjusted up, down or sideways. It took me a few tries to get the shaft turning smoothly in the cutless bearing. I also had to add a small shim at the bottom of the strut.
With darkness fast approaching, I mixed up some very thick epoxy and spread it around the bottom of the strut, and a few spots on the top to hold it in place. Next step will be to pour epoxy from the top to fill all the voids, and then glass it into place.