Thursday, April 19, 2012

Outboard Motor Update

You will remember that one of the casualties in Cyclone Cyril was our 17-year old Nissan 5hp motor. When our dinghy was ripped off the stern by the wind and Sea Flyer's bow, the motor was torn in half and the head part sunk in 30 feet of water. We retrieved it as soon as the storm moved off, and did an initial freshwater rinse in a tub of water.

Then Larry from the Ark (who's moorings we were on when we dragged) took it to his Tongan mechanic, who rinsed it some more, and then moved our "guts" into an old Nissan foot and bracket that Larry had. It took several weeks, but Larry presented us (without charge) with a supposedly working motor. However, it still had problems, and Dave has spent a lot of time over the last month or so trying to get to the bottom of the intermittancy (see past blog posts).

Dave thinks he has finally gotten to the bottom of the (hopefully) last issue. This is what he wrote a friend a couple of days ago:

"After a month of fooling with it I finally figured out a couple of days ago what was wrong with my 5 HP Nissan outboard. It had been underwater for 2 days after the storm and then another couple of days in fresh water. I couldn't figure out why it would run for about 10 minutes and then after turning it off wouldn't start and had no spark. Then with a different plug it would spark but would not start until much later. But it would always seem to fix itself and restart."

"It seems the local mechanic that I let flush the engine for me took the power head off and broke the gasket that separates cooling water from the combustion chamber exhaust. He must have put it back together without even looking at the gasket. I violated my own rule: never let mechanics work on your stuff without being right there to supervise."

"So it was sucking salt water mist into the combustion chamber after shut down, and maybe while running, and fouling the plug. The hint was when I finally noticed the miniscule water droplets on the plugs after it had been running."

"Then I broke one of the five head bolts getting the power head apart to reflush everything. Luckily the local machinist, who is excellent, was able to get the broken bolt out today. I now have the motor all cleaned out and back together just waiting for the new gasket a cruising friend is bringing up from NZ next month. So hopefully, mystery solved."

At 04/14/2012 7:26 PM (utc) our position was 18°41.34'S 173°57.56'W

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