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April 3, 2011 at 8:28 pm #6560Anonymous
Hi all,
Just a query to see what the groups thoughts are on potentially disabling the noisy extract fan from the new Bavs engine bay?
I understand the need in warmer climes or even if the engine is going to be run for hours on end….. but does it need to be so loud?What are your views on inserting a switch or even an automatic sensing unit so that it only runs when required?
What are the risks / implications?Steve
April 4, 2011 at 5:11 pm #8628AnonymousCan I ask what boat/engine we are discussing here? Is it a motor boat with hundreds of horsepower?
My Year 2000 sailing boat does not have an engine blower (with a 50HP engine) and, in my (albeit limited) experience of the sailing boat range, none of those do either.
However, it is common practice on larger motor boats to fit blowers.
April 4, 2011 at 7:06 pm #8629AnonymousHi Steve,
To answer Roger’s question and if I remember correctly, you are the proud owners of a new Cruiser 32.
Lots of noise from bilge blowers can be traced to the shape and angle of the vents on the outlet causing turbulance and for want of a better description, playing a long note, rather than just exiting cleanly and quietly. You may wish to remove the outlet vent and assess if the noise reduces with the air exiting straight through. If that produces a more acceptable tone then perhaps a change of vent is all that is required. You may also be able to reduce the volume of air being moved with the cunning use of a cable tie around the pipe to produce a restriction or by taping over the inside of the outlet vent although this sometimes can accelerate the air to produce a higher pitched noise.
Personally I would leave it working as is. Bavaria have never knowing added any extra to their boats that isn’t required!
Take care
Paul.April 4, 2011 at 7:39 pm #8630AnonymousHi Paul
Do I understand from this that Bavaria are fitting blowers on the sailing boats these days? When did they start? I am obviously losing touch!
What has changed on the newer boats to require inclusion of a blower? Maybe there is a new EU Directive?
I must admit I find it hard to believe that a blower is really necessary on a 32. Small diesel auxiliaries have been operating for 10s of years without needing a blower!
Roger
April 4, 2011 at 8:34 pm #8631AnonymousI’m also intrigued as to why they have started installing blowers in the engine bay on the newer yachts.
I can fully understand it on petrol engines with the risk of fuel vapour etc but as Roger says why small inboard diesels.
Perhaps Steve Gunn could shed some light on this?
Cheers
RickApril 4, 2011 at 9:07 pm #8632AnonymousI don’t know for sure why they have started fitting bilge blowers but I suspect that with the redesign of the cockpit, the drop transom and the constant pressure to provide large aft cabins and heads that they have created a captive space in the engine bay which retains the heat. I also suspect that they have increased the Db rating of the sound proofing which is creating a more thermo efficient barrier so the heat isn’t disapating as effectively as it used to.
This retained heat would have a knock on effect on the engines meeting the requirements of the latest tier III regulations and the incoming Tier IV regs. Perhaps Volvo are struggling to get a clean burn with hot dry air and need the increased density of fresh cooler wet air to reduce the emissions.
All of course pure spectulation but based on some previous experiences.
cheers
Paul.April 4, 2011 at 9:38 pm #8633AnonymousOk Clever cloggs.
What does “spectulation”mean?April 4, 2011 at 10:29 pm #8634Anonymous@Sundance wrote:
Ok Clever cloggs.
What does “spectulation”mean?It’s Cornish for ‘guess’!
April 5, 2011 at 8:54 am #8635Anonymous@hunros wrote:
I don’t know for sure why they have started fitting bilge blowers but I suspect that with the redesign of the cockpit, the drop transom and the constant pressure to provide large aft cabins and heads that they have created a captive space in the engine bay which retains the heat. I also suspect that they have increased the Db rating of the sound proofing which is creating a more thermo efficient barrier so the heat isn’t disapating as effectively as it used to.
This retained heat would have a knock on effect on the engines meeting the requirements of the latest tier III regulations and the incoming Tier IV regs. Perhaps Volvo are struggling to get a clean burn with hot dry air and need the increased density of fresh cooler wet air to reduce the emissions.
All of course pure spectulation but based on some previous experiences.
cheers
Paul.That all seems to make sense – except the bit in Cornish!
Thanks
Roger
April 8, 2011 at 8:27 pm #8642AnonymousLOL
Thanks guys for all the info so far…. especially the Cornish bit!!
Kind of makes sense with regard to the lean burn etc, but would not fitting an external air intake have made more sense than installing the “vacuum cleaner”?
All of the so called evolution in sound proofing is far outweighed by having this noise in the background.
Is it really necessary?
It is only the D120 unit …..Short of going down the Dr Pepper advert approach of “What’s the worse that can happen” (engine catches fire, boat sinks, everyone dies!) – Is there another approach?
I agree that Bav do not fit all of their kit “because it is nice to have!” – with most of it being necessity….. but is this necessity in the UK / Channel?
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