I've been running Speedmaster Stinger with 3/16 propeller shaft and .078 wire drive.
In the last months I've tried to seal the stuffing tube from the inside with a piece of silicone tubing with medium result. The silicone tube seals very good for the first couple of discharges and then begin to leak again due to the wear.
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I read here on this forum on one thread to use a grommet or cut a piece of silicon line and put it between the drive dog and the strut/stinger.
So instead of a grommet I took an o-ring made of viton with dimensions internal diameter 4,6mm and cord diameter 2mm (I have it at works).
For the first 3 discharges and for a time of about 25 minutes I had a perfect dry boat inside.
Now I have both seals inside and outside.
I'll keep on testing this solution and will report here the results.
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