Okay boys and girls today’s lesson is about Water Lift Silencers. What in the world is that? Well, I’ll tell you Shouty. It’s that round thing under the deck behind your engine that helps the exhaust push the water out the exhaust port usually somewhere near the aft your your boat. It can easily be located when your engine is on and the water and gases are spewing out into your wake.
There are all kinds of lift silencers but this one is mine. Dazzler is fitted with a very old fiberglass style with both the exhaust in and out ports on its top. It is a cylindrical sealed can with an approximate 1.5” flange on its bottom for fastening it to a platform.
So what’s all the trouble with these things? Do they have a life expectancy? Can they go bad? If so, what causes them to go bad? I sum up these questions with our experiences over the last several days.
First, I’m not sure if this is the original lift silencer on Dazzler or not. I suspect so though. I have owned her since 2003, and she is now 32 years young. I knew where it was located, but honestly didn’t know much about how it worked or what to look for in the way of issues. One of the two previous owners had it installed or installed it themselves. When it was installed, the angle of the elbow that connects to the back of the engine apparently was modified from a 90° elbow to an approximate 30° down angle. During the modification process, as determined by the crack I found, a regular 90° elbow was cut to accommodate the needed angle and a putty similar to the Minute Mend that I used to make our emergency repairs was used to complete the modification. Perhaps the instant epoxy has a use life also. Years of vibration and almost 6000 hours on the engine had finally hit that magic age of disintegration. LOL How do I know these things?
Well, two days ago the engine stopped spraying water again. No big deal as we’re just putting up the sails again. We sailed through the rest of the night and into the next afternoon before I had to tackle the new water leak situation again. It seems that I missed this crack because I couldn’t see it during the second fix. Hence I pulled the entire silencer out of the engine compartment to better diagnose and attempt to fix ANY and ALL cracks this time.
I guess third time is a charm. After grinding the areas around the several additional cracks I found, I filled up the canister with water to see if it had any other leaks. It’s flat bottom is also fiberglass and is joined to the flange of the bottom of the canister. When it was installed. The installer drilled through the flange and into the mounting deck. This held it firmly in place but it also put eight screw holes into the flange that apparently should have been avoided as all eight holes leaked water. I’ll tell you how I tried to fix this issue later. While the minty flavored dog poo was setting up From the new application, I refitted the silencer to its mounting deck. I used some wazoo pipe thread sealer I found in Papeete on the screws before I inserted them and fastened the silencer down. Yes, I magically found all eight same screw holes without too much difficulty. Not bad for upside down blind left handed screwing. Actually, I used a Sharpie marker and marked one of the holes and as for the rest the silencer just kind of fit in place. Both hoses were connected as designed. We waited an extra 10 minutes for it to set before I fired up the beast. You’d have thought I was waiting for Santa to come down the mast or something. I was impatient so I found putting away tools occupied me for several minutes while I waited. We fired up the beast and tada! No leaks from the hose connection. Yay! The bottom of the canister was a different story.
As it turns out, one of my Diesel engine repair manuals by Nigel Calder talks a little about the water lift silencer. Apparently a back pressure 1.5 PSI is present to help force the water out to the back of your vessel. That’s good because I’m not sure I could seal it up for any more than that. Additionally, Mr. Calder recommends breaking lose your exhaust connections and inspecting the inside of hoses for excess soot, oil or anything else at least once a year. Catch it before the surprise of not working properly when you least expect it. It will be on my annual inspection to do list from now on.
To answer the question of what the life expectancy is would be like answering the riddles of the universe in one word. They may, but I would recommend routine checks while servicing your engine. You know hands on eyes on while it’s running if possible. I have to admit that this was not something on my radar of things to check. To make sure it doesn’t develop a crack like ours did for whatever reason, defect, installation or old age, I’ll be checking our new one during regular engine services in the future. I only look upon our repair as an emergency repair and yes, we will be getting a new one in New Zealand.
I write this for all my boating friends out there that at the very least ask their own questions. I wonder if mine might be leaking? Do I have one of those? Is it in good working order?
If this helps just one other person to avoid potential exhaust water lift silencer issues then right on!
Now it’s back to sailing in a cold, cloudy environment. We are less than 200 nautical miles from Marsden Cove Marina where we will check into Country with Customs, Immigration and Bio-Security. We have about 14 knots of wind out of the North on our port quarter, the seas are relatively flat and we’re making 7 knots. Hang on Grape Ape! He likes to be part of everything. What are you gonna do? Teenagers!