.
.
.
Might be a silly question but I assume I’m ok just putting the new one in dry and turning the engine on? I don’t need to pre fill it or anything do I?
Not a silly question if you don’t know or are unsure, but yes, that’s right. Fit it dry, connect the hoses, one from engine to silencer and one from silencer to exhaust overboard outlet. When it’s all secure and your saildrive water inlet valve open, start your engine and water flow overboard will start within a few seconds. Yes, it will take marginally longer for water to get from the engine to the exhaust overboard the first time you use it after fitting the replacement silencer, but thereafter it will be the same as before. If water should not appear within, I’d say ten seconds, then it’s likely something has been forgotten and at which point you should stop your engine and go and look for whatever has been forgotten. Assuming water flow appears as normal, then go and check the entire exhaust system to make sure your connections are not leaking water. Blue absorbent tissue paper spread under and around the exhaust hose and silencer is particularly good at showing up any water leaks. Lastly give the engine a run for twenty or thirty minutes and check again for leaks. It should be all secure, but if not then make the necessary adjustments to stop the leak, and check again. Once you are happy then that’s it until you next put to sea when you should carry out further periodic checks, especially if your engine is likely to be run for lengthy periods.