Aboard Astraea

Invest in experiences, not things

Waterlift Muffler Replacement: Day 1


I received the new water lift muffler from Vetus Marine in the mail on Wednesday. Upon closer inspection of the cooling system I found that the water output from the engine goes through a high point with an anti-siphon valve at the top. This prevents water from being pulled through the low point in the water lift muffler and backing up in to the engine. The anti-siphon segment is 1″ diameter hose and is 10 feet long. I needed to calculate that additional volume, so in to the volume equation it went, ∏r²h. 3.14159 * .5 * .5 * 120 = 94.2477 cubic inches of water. Converting that to gallons it’s about .41 gallons. Add that to the original calculation of about 3.5 gallons and that’s about 3.8 gallons. There’s still extra capacity in the waterlift muffler to handle that.

This diagram better illustrates the setup of the cooling system on Astraea

This diagram better illustrates the setup of the cooling system on Astraea. Credit: Moyer Marine Forums

Chuck from Wind Watcher came over on Thursday to help me clear a hole in the bilge to get ready for the replacement.

All systems intact

All systems intact

Removing the electrical connections from the water heater. They had waterproof sealant applied over the terminals to prevent shorting if the bilge floods.

Hoses off and coolant connections bagged and sealed to keep coolant from getting in the bilge

Water heater removed. It was held in by four screws.

The shelf was cut away and will be replaced. The bilge pumps are temporarily relocated to the sides of the bilge.

Without the water heater there is a big empty space

The removal process was pretty straightforward. If it is above the old waterlift muffler it came out. We’re going to be dockbound until the new muffler is installed. I’ve arranged for pump out service on Wednesdays from Pepe le Poo. The potable water pump is turned off because the hoses that were connected to the hot water heater are removed, but I’ll get the hoses reconnected so I can turn the water pump back on for Natalie. The foot potable water pump in the galley is a big pain to use and is only a last resort.

Saturday I’ll have Henry Wing from Wing’s Diving help with moving the propellor shaft back so I can get the old muffler out and test fit the new one. There are other options to get the water lift muffler in. I could pay $410 to have the boat hauled out at Knight and Carver boat yard and pull the shaft back myself, or remove the engine. Henry has done this kind of job before so we’ll give this a shot first.



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