SimonA
Well-Known Member
I've got a boat with a BMC 1.5 diesel engine and Bowman heat exchanger/manifold/header tank which is typical of many BMC installations. The water injection elbow is not far above the water level, currently it drops down to about water level, runs across and is connected to an Elastomuffle (1970's style muffler made of rubber) which is connected to the exhaust through hull fitting by a jubilee clip.
I've read up on water cooled exhausts and it seems the general advice is to have the water injection elbow at least 30cm above the water line, mine isn't, or to have a water trap (I don't have one).
My concern with the current installation is that A) if the elastomuffle fails the boat could sink as the exhaust is about 5cm above the water line. B) water could flow back down the exhaust into the engine.
Am I being paranoid (after all it's probably been this way for many years) or should I replace the current arrangement with a water lock followed by a swan neck in the pipe before exiting the exhaust?
Image attached of current set up.
I've read up on water cooled exhausts and it seems the general advice is to have the water injection elbow at least 30cm above the water line, mine isn't, or to have a water trap (I don't have one).
My concern with the current installation is that A) if the elastomuffle fails the boat could sink as the exhaust is about 5cm above the water line. B) water could flow back down the exhaust into the engine.
Am I being paranoid (after all it's probably been this way for many years) or should I replace the current arrangement with a water lock followed by a swan neck in the pipe before exiting the exhaust?
Image attached of current set up.
