Shaft strut straightening help

mongo75 · Feb-19-2008, 09:10 AM

It was hard enough typing that- try saying it three times fast- ANYWAYS I'm looking for a place that will straighten out the prop shaft strut for my inboard project. It almost looks ok, kinda like it was installed with a little bend in it, but I don't like it so I want it straight. Advice??

bertram31 · Feb-19-2008, 01:09 PM

There really is no perfectly straight componets of a inboard stern tube set up. Sure if the strut is bent to hell it can be straightened in any prop shop.

What matters is your alignment. You need to mock up the shaft package right to the tranmission coupler. Sometimes this take moving the engine from side to side to not hit the stren tube. Remember the tube is the only part that cannot be changed. The location of the strut is irrelvent. Shipyards use a product called Chalkfast, which is a epoxy bonding/filler product, to set the location of the strut. It gets really fun when you have two strut as most big boats do.

Another tool helpful for this job is a false bearing. Have a machine shop turn you out a sleeve to go over your prop shaft and fit inside the sturt. Give yourself a couple thousandths of an inch difference for easy movement. This will hold the shaft tight inline and turn freely when there is no bind. You now are good to go on alignment, as long as you have the shaft close to the center of the stern tube. Dont forget you install a new cutlass bearing in the strut.

Jack

mongo75 · Feb-19-2008, 08:41 PM

Jack,
Thanks for the response. Right now I have a bare hull- just stringers and the gunnel tops I just put on, so I got room to work with. Although I am going to replace the last 12' or so of stringers, I was thinking I could just bolt the strut back on, and then clamp on the PSS I got and run the shaft up and after it's "held" in place with minimal binding (if any) I can align the V-drive to the shaft, and then the velvet drive / engine package. BTW I have the new cutlass bearing in the freezer right now hehe

bertram31 · Feb-19-2008, 10:50 PM

That will work fine. You have the stern tube/shaft log allready through the boat. Use the strut you have and that will set the angle of your prop shaft, the location of where it bolts to the boat should be fine. From this point, yeah set the engine mounts and align the engine to your now fixed strut/stern tube combination.

Good luck with the project.

Jack