outboard mounted on transom

[John Peter Mitchell]

Good morning Glenn,

Yes, the engine is firmly wedged between the modified mount and the transom: there is some pressure on the transom forward face just under the manufacturer's I.D. plate.

When I run the engine at sufficient rpms to produce ~5 knots of boat speed, there is an annoying amount of rattling.  I discovered that the source of the rattle is the top rudder pintle shaking in the gudgeon.  I have yet to address that.  I'm thinking of wrapping the pintle in something to isolate the two metals(???). Perhaps a thin rubber finger protector.  On the other hand, your thought may be the best solution: to keep the engine away from the transom...  It may call for a smaller engine in this space(?).

On another concern, which you had written about earlier in this thread, the exhaust fumes in the cockpit.  Rick Bera, a former acquaintance of my Ontario days, described his solution to this problem.  My engine also has an exhaust pressure relief mounted on the back of the engine just below the engine head.  Rick Bera described two diverter hoses and posted a great picture of those emerging from the transom scuppers.  I have just one clear plastic hose (1/4" I.D.) attached which is 36" long.  This hose can be put through either cockpit scupper.  That may solve your exhaust fume problem.  

[Pkeane49]

I recently moved my Yamaha T9.9 out of the well and onto the transom using a Panther bracket.  I have also added remote shifting and throttle.  The motor is no longer a barnacle magnet, as I can swing it clear of the water at the dock.  True, I have lost some of my maneuverability in close quarters, but the cockpit is much quieter when motoring and I have gained about a knot and a half by being able to swing the motor out of the water when sailing (cutting drag from the lower unit and 11" propeller) and also plugging the well flush with the bottom.  I'm very happy with the arrangement.  Next spring, during haul out, I plan to glass over the well completely

[John Peter Mitchell]

Wow!  1.5 knots of drag would be disappointing for most sailors.  Could the "magnetic barnacles" have been the main cause of such a drag on the boat speed?

By routinely lifting my outboard clear of the sea water after each use, I have yet to attract any barnacles.  I also follow my Yamaha instruction book's suggestion to rinse the engine's cooling passages with fresh water for a minimum of 15 minutes after each use.

I do envy your noise reduction, of the engine's noise, by positioning it onto the outside of the transom.  There are pros and cons each way...  Good luck with your new bracket.  JM

[Pkeane49]

Hi John,

With the size of the prop on the T9.9, there was no way to get it through the well opening to keep it out of the water.  As mentioned previously in this chain, you have to put the motor in the well still while on the hard then attach the prop prior to splashing. With my old Honda 9.9 (circa 1983) there was no problem lifting it out of the well and propping it up on a 2x4 slung across the cockpit seats when docked.

Once back in port, I routinely disconnect my fuel line and let it run out of fuel, meanwhile I connect a fresh water hose to the specialized flushing port on the motor and flush it after every use.  Makes a huge difference based on what I found in the old Honda when I took it apart.... large deposits of green salty guck in the cooling passageways.

The power tilt on the new motor makes it easy to lift it clear of the water while under sail.

You're right about the trade-offs, but I'm pleased with the choice I made.