Five things:

Joel explained a drain tube that was added on SM hull number 400 and above. You have 278.

I believe you said that yours leaked without moving the boat. If so your bow is too heavy and too low in the water.

I believe the service intervals should be about every two years

You do not mention securing the bow thruster with the locking pin

Do you read the recent post whereby Amel recommends a slightly different size lip seal? It reads:
"2 weeks ago, I received many spare parts from Amel (La Rochelle), as I was labelling them I noted that the seal on the tufnol shaft bow thruster was 29 x 42 x 8. 

Thinking it was an error, I contacted Maud which just confirm that they have modified a little the diameters of the seal so that they are more water tight. 
Before it was 30 x 42 x 8 now it is 29 x 42 x 8 she added you won’t be able to put them by hand, but will need to grease and use a tool “emporte piece” in french." 

I believe that you need to address and/or understand all of the above.

Bill Rouse
BeBe Amel 53 #387
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