Anyone have experience with a leaking stern tube and its replacement/repair?
The shaft is stainless, but the sterntube appears to be bronze(still encased
in the keel), both materials of unknown (Taiwanese) quality. On a 17 year old
boat, the problem cause is likely electrolysis. Have heard of using
fiberglass tubing. Suggestions?
Don wrote: < Anyone have experience with a leaking stern tube and its
replacement/repair?>
We had to replace our stern tube after 30 years. It was a thin, schedule 10
perhaps, SS tube threaded onto the bronze cutlass bearing support at the aft
end and the bronze stuffing box at the engine end. It would have been easy
except that it ran through the stern tube tunnel which was filled with
concrete ballast!! Getting complete access required removing the genset, 2
fuel tanks and a few other minor items in the way. Not for the faint hearted
:-(
After a couple of weeks of chipping the concrete out we removed the old tube
and both ends. We then installed an Evolution Marine shaft system. More
expensive purchase than just replacing with the similar tube and bronze ends
but a much superior system, IMO. Also a drop in job in our case as we had
measured 3 times ;-) In the end I think the unit saved a lot of local labor
costs. It ran 15 BU's total! The boat yard here would not quote the job
doing it the conventional way but estimated $10 to 20K. I expect it would
have been more than $20K!!
Going the simple replacement way you need a schedule 80 fibreglas (you can
use 316 SS Schedule 10/20 but will have trouble getting the bronze and SS
threaded) tube and new bronze ends to match up with your shaft size and the
tube size. Measure twice, cut once, dryfit and make sure that the tube
carries no compression load after you bolt up the stern fitting. It is only
there to keep the water out :-)
In most boats this is a big job and needs professional expertise which is
hard to obtain as this is not an oft occurring problem.
Good luck!
Dave & Nancy
Swan Song
Roughwater 58
Tortola, BVI