Tohatsu 6 HP went for a swim

PaulAB

Recruit
Joined
Jul 20, 2017
Messages
2
My grandson was operating his father's inflatable all day and somehow the engine came off the transom and went into the salt water. It was in for only a couple of minutes. I picked up the engine and within the hour had drained the carburetor and oils, replaced the spark plug, oiled the cylinder and sprayed a liberal amount of CRC on the engine. The engine fired right up and sounded good on idle and mid-speed, but shuttered at anything over half throttle. Thinking the carburetor needed to be cleaned, i took it apart and cleaned it (a couple of times) but still had the shutter. I bought a new carburetor and installed it and still had the shutter. I connected a timing light to the plug and at idle through half throttle has a constant spark, but past that the spark breaks down. I disconnected the kill switch with no change. The engine was built in 2008 and has the "new" magneto. I replaced the igniter thinking that was about the end of the electrical issues. After replacing the igniter it still has the shutter. I am now growing an inventory of spare parts without resolving the problem. What am I missing?
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
You might as well replace all the electronics anyhow, after a salt water dunk, even if they work right away, they tend to die from corrosion over the next little while.
 

Chigwalla

Petty Officer 2nd Class
Joined
Jul 11, 2017
Messages
109
Not sure what you mean by igniter and magneto ? Trigger and stator ?
There are a few tests (mainly resistance checks) you can do for the trigger, stator and coil.
And yeah, assume anything with copper is done for.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
When an OB goes diving in sea water, OB should be inmersed in fresh water inmediately after recovery for say 1 hour to get rid of salt specially on parts that can't be easily accessed. If only has been rinsed with fresh water, expect internal bearing & rotating parts seizure in the short run due to corrotion.

That OB went down due to adjusting clamps went loose during operation, clamp adjustments should be adjusted periodically.

Happy Boating
 

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,559
Not sure what you mean by igniter and magneto ? Trigger and stator ?
There are a few tests (mainly resistance checks) you can do for the trigger, stator and coil.
And yeah, assume anything with copper is done for.
No, that motor does not have a stator. It has a single-piece ignitor.
 

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,559
My grandson was operating his father's inflatable all day and somehow the engine came off the transom and went into the salt water. It was in for only a couple of minutes. I picked up the engine and within the hour had drained the carburetor and oils, replaced the spark plug, oiled the cylinder and sprayed a liberal amount of CRC on the engine. The engine fired right up and sounded good on idle and mid-speed, but shuttered at anything over half throttle. Thinking the carburetor needed to be cleaned, i took it apart and cleaned it (a couple of times) but still had the shutter. I bought a new carburetor and installed it and still had the shutter. I connected a timing light to the plug and at idle through half throttle has a constant spark, but past that the spark breaks down. I disconnected the kill switch with no change. The engine was built in 2008 and has the "new" magneto. I replaced the igniter thinking that was about the end of the electrical issues. After replacing the igniter it still has the shutter. I am now growing an inventory of spare parts without resolving the problem. What am I missing?
If you exceed the proper speed for WOT, the ignition will stutter to limit RPM and keep the motor from blowing up. You must test under load in the water. If you are testing unloaded, your results are normal.
 

PaulAB

Recruit
Joined
Jul 20, 2017
Messages
2
Thank you, mounted the motor on the inflatable last night. Runs like new again!
 
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