New Zealand Gold Prospecting & Metal Detecting Forums Archive

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Quietening a dredge?

WagonWheel		Posted : 12 years ago
Rank: Gold Dust Groups: Registered Joined: 13/08/2012(UTC) Posts: 3 Location: Southland Thanks: 1 times		Hi all, I have a 5.5hp Honda based/copy engine, I was wondering if anyone had any tip/tricks, DIY/homemade solutions to quieten it. I would just like to try and make it more quite as to save my hearing if I'm going to be working less than 3 metres away, I know ear buds would be a cheap compromise but I don't really want to p!ss anyone else off with the noise, Any suggestions would be greatly appreciated, Cheers

pc5001		Posted : 12 years ago
Rank: Gold Flake Groups: Registered Joined: 5/08/2011(UTC) Posts: 26 Location: central otago nz Was thanked: 13 time(s) in 8 post(s)		Wrap exhaust insulation around your muffler and if possible extend your exhaust into the water,about 75 mm below water level should lower the decibels a bit. You should also ask yourself if you need to use full throttle, check the performance at lower revs, if you need full throttle all the time there maybe modifications you can make to the powerjet ,height of the sluice,or the size of the jet or pump ports that will improve performance and lower the revs

WagonWheel		Posted : 12 years ago
Rank: Gold Dust Groups: Registered Joined: 13/08/2012(UTC) Posts: 3 Location: Southland Thanks: 1 times		Hey, cheers man, some good suggestions there that I'm going to try out. I 'll let you know how I get on Thanks again

mad mike		Posted : 12 years ago
Rank: Gold Dust Groups: Registered Joined: 20/03/2013(UTC) Posts: 3 Location: hari hari		build a insulated box round pump and moter with some skinny ply and chicken mesh on inside to hold pinkbatts in place i made similar for generator worked really well. but may be too heavy for dredge?

Moonlight Picker		Posted : 12 years ago
Rank: Gold Nugget Groups: Registered Joined: 30/01/2013(UTC) Posts: 48 Location: ashburton Thanks: 4 times Was thanked: 1 time(s) in 1 post(s)		Hi Some Motors are noiser than others. Half the time the muffler can be same of the problem, But most of the time its the motor, just noise, some time cheep not the best, If noise is a problem you might need to look in to the decibells that they put out, as they are same motors on the market .. you can wrap the muffler or box the motor. But heat becomes your next problem, but the exhaust in to the water is a good one to try, and see if that fixs the noies.. hope you find a fixs

pc5001		Posted : 12 years ago
Rank: Gold Flake Groups: Registered Joined: 5/08/2011(UTC) Posts: 26 Location: central otago nz Was thanked: 13 time(s) in 8 post(s)		you will have to be very careful building any kind of a cover or box around your pump motor.Your motor is air cooled and should be completely open to the atmosphere to operate safely Shrowding could increase temperatures enough to glow the exhaust red,causing the sound proofing to ignite...all while you've got your head underwater...

gavzilla		Posted : 12 years ago
Rank: Gold Nugget Groups: Registered Joined: 24/02/2012(UTC) Posts: 60 Location: queenstown Thanks: 12 times Was thanked: 34 time(s) in 18 post(s)		I changed my whole exhaust for a modified scooter exhaust once, just drilled out the holes and made a good seal with manifold gasket and paste, worked a charm, but as mentioned engines are just noisy in general...

Moonlight Picker		Posted : 12 years ago
Rank: Gold Nugget Groups: Registered Joined: 30/01/2013(UTC) Posts: 48 Location: ashburton Thanks: 4 times Was thanked: 1 time(s) in 1 post(s)		Hi How did it go. did you fix the problem, it wounld be great to hear