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Hospital Silencer

Narrowboat Exhaust Hospital Silencers - Hospital Silencers For Marine Diesel Engines

Hospital generator silencers are especially quiet and suitable for linear and residential moorings where the running of the main engine or a generator would be anti-social.

Recently Graham and Jean Beven, Partners and owner of www.CanalCuttings.co.uk were moored directly behind a friend's boat at Norbury Junction. One morning Graham was sitting on the bow of Narrowboat 'Maid Of The Mist' and heard what he thought was a washing machine 'pulsing' aboard the boat in front. When the skipper Frank emerged after an hour or so Graham commented that the washing machine was on for a long time. Frank said he hadn't got a washing machine; the sound was the boat's engine. It turned out that Frank had fitted a 'Hospital Silencer' and Graham who is just a tad deaf anyway couldn't actually hear the engine of the boat in front running.

Before they did anything drastic Graham lined the engine compartment with noise suppressant sheets, which did deadened the noise of the 'engine' somewhat but the exhaust seemed even louder!

As Maid Of The Mist was probably going down to the London and south eastern canals for three or so months over the winter the boat was fitted with a hospital silencer when she went in for her next service. The bill for the parts/VAT included was £368.38 which included: 4 hours labour, 1 hospital silencer 12"x32" (nominal), 1 roll of exhaust lagging, 1 navel joint. We were discounted by the fitters: J D Boat Services, The Wharf Watling Street Gailey, Stafford, Staffordshire ST19 5PR p: 01902790612 f: 01902791446 on the silencer as we are regular customers of theirs.

When Jean and Graham heard the results the exhaust noise was greatly suppressed! Instead of being able to hear the boat on tick over at around a distance of 60feet, the sound perception distance was down to around 12feet.

Hospital silencers for marine diesel engines; Yes! - Whilst cruising the noise level is so much reduced you can actually converse with crew on the towpath without raising your voice!

A recent post on one of the Canal Forums asked - "Is it worth fitting a hospital silencer instead of a standard one? Our engine is going in next week and I've been quoted around £100 for a standard silencer for our Beta Greenline 43bhp engine, and about £150 for a hospital silencer. Is it worth spending the extra £50 or so?"

Since they started cruising again Maid Of The Mist has run her engine whilst moored in series ahead of other boats and their owners have observed the lack of noise. Graham and Jean believe they will be able to run the engine in Paddington Basin, next to the hospital, after spending the day making use of their bus passes visiting free London museums and galleries as well as taking in free evening shows too!

HOSPITAL SILENCER 1.1/2" BSP END/SIDE OUTLETS
General Specification:- These silencers are recommended for use on diesel exhaust gas lines where noise levels have to meet the most critical specifications, without creating excessive back pressure. They are designed using the well known reactive and absorption principles and the unique configuration combines these together to produce the most effective attenuation over a wide band. The design gives low noise break - out and surface temperatures.

Construction:- A cylindrical shell manufactured from heavy gauge sheet metal, fully welded. All plates are manufactured from flat plate. End connections are 1.1/2" bsp screwed, top and side entry.

Footnote on Hospital Silencers

It would appear that many well designed engine installations are let down by poorly thought through and badly constructed exhaust systems. There is not a better example of the saying 'you don't spoil the ship for a ha'porth of tar' . We are not suggesting that a good exhaust system comes as cheap as that, but we now consider it money well spent. Maybe all new build narrowboats should have hospital generator exhausts fitted as standard. Not that we are going to start a campaign!