Eberspacher silencer

2

[2574]

...
Joined
29 Nov 2002
Messages
6,022
Visit site
I have acquired a proper marine sealed Eberspacher exhaust silencer - is it best to fit it with the silencer being closest to the heater or closest to the transom exhaust fitting?
 
In cars silencer is fitted just before the end of exhaust, aren't they? (i'm not a specialist). In my boat the heater is at the floor level, and the silencer is somewhere chest level. I don't remember the shape of exhaust between silencer and transom fitting. Might have an extra loop before it comes out.
 
If the silencer allows the exhaust gas to drop below 100degC, then it must let the water drain out.
Burning diesel creates a lot of water.
Which might suggest putting it above the transom drain?
 
Recommendation is fit as close to the heater as practical, well lagged to retain the heat, so just shorten one end of the exhaust pipe that is welded to it, your mooring neighbours will probably buy you a beer when they see you in the bar.
 
Last edited:
I don't understand how a silencer works - anyone prepared to explain in simple terms? Ours 'roars'. and it's hardly discernable inside, but outside you can hear it from the pontoon. (ours is not the noisiest in the marina by far, so not particularly worried and all our neighbours have them running at the moment). Do silencers really reduce the noise of it?

Our unit is fitted in the engine bay and the exhaust disappears under the floor for a metre, then emerges in the wet-locker before rising 1.5m to the vent. Having googled silencers, I don't think we have room to put in next to the heat, but could I put one in the locker - which would be about half-way along the exhaust pipe?
 
ChattingLil said:
I don't understand how a silencer works - anyone prepared to explain in simple terms? Ours 'roars'. and it's hardly discernable inside, but outside you can hear it from the pontoon. (ours is not the noisiest in the marina by far, so not particularly worried and all our neighbours have them running at the moment). Do silencers really reduce the noise of it?

Our unit is fitted in the engine bay and the exhaust disappears under the floor for a metre, then emerges in the wet-locker before rising 1.5m to the vent. Having googled silencers, I don't think we have room to put in next to the heat, but could I put one in the locker - which would be about half-way along the exhaust pipe?
Click to expand...

Massive reduction
 
"" Originally Posted by ChattingLil http://www.ybw.com/forums/showthread.php?p=5073396#post5073396 I don't understand how a silencer works -""

By partially holding back the pulses (of pressure/sound) and then letting a smoother flow of gas reach the outside world.

A perfect silencer would output smooth, low velocity, non turbulent, non resonant gases.
 
Last edited:
The exterior difference in a diesel heater without an exhaust silencer is huge, adding a simple air intake tube, or better still a silencer to to the combustion air intake makes a similar interior difference. Marine kits do include both. I recently fitted a 30kw Webasto heater to a boat and you really wouldn't know it was running unless you were right next to the exhaust.
 
ChattingLil said:
Our unit is fitted in the engine bay and the exhaust disappears under the floor for a metre, then emerges in the wet-locker before rising 1.5m to the vent. Having googled silencers, I don't think we have room to put in next to the heat, but could I put one in the locker - which would be about half-way along the exhaust pipe?
Click to expand...

Unfortunately the marine silencer is around 2 to 2.5m long including the exhaust pipe and would be too short for your installation. Contrary to my usual advice you would need to cut the pipe and insert one in the locker, the vehicle ones from Webasto & Eber are unsuitable both in effect and safety on a boat so again contrary to my usual advice you would need to find an after market one (gas tight). Be sure to use exhaust assembly paste, lag it well and use good quality stainless Mikalor clamps or similar.
 
Yes, lower airflow and a burner that is not forced like Webo, Eber, Miki the burner is simply put, a little puddle of diesel with air supplied under very little force, horizontal rather than a sintered vertical gauze with heavily forced air. The heated air volume is also quite a lot lower, hence the need for two outlets on the heater instead of one with high volume.
 
Many thanks for the info, now I know why it takes more space than the other type. I am in love with it but not as much as I love the Wallas oven and hob. The latter has been in regular use for 5 years without missing a beat (the pump beats like a heart and great for getting to sleep to, can just barely hear in background) and I am wondering if it must be time for a service, no schedule given in handbook?
 
David,

Many thanks for your guidance. One last question - if I am to cut short one of the tubes welded to the silencer (to facilitate its close proximity to the heater) then I am going to have to extend the other end to reach the skin fitting. Is there a steel sleeve available which can be inserted to the two pipe ends to joint two pieces? Or do you use a 24mm (od) bit of any old pipe?
 
Robih said:
David,

Many thanks for your guidance. One last question - if I am to cut short one of the tubes welded to the silencer (to facilitate its close proximity to the heater) then I am going to have to extend the other end to reach the skin fitting. Is there a steel sleeve available which can be inserted to the two pipe ends to joint two pieces? Or do you use a 24mm (od) bit of any old pipe?
Click to expand...

In that case I would prefer to see no joints, the silencing difference will be minor and retaining the gas tight integrity is more important. You can use a short length if tube to join if you make sure it is well sealed.
 
GrahamM376 said:
Problem when looking for silencers is the price differential and types, for example both of these are quoted as 24mm "marine".

http://www.ebay.co.uk/itm/24MM-MARI...ERSPACHER-WEBASTO-DIESEL-HEATER-/111490835854

http://www.ebay.co.uk/itm/Webasto-o...Silencer-NEW-LOW-PRICE-9014067A-/271199113814

Is the cheaper type suitable or not?
Click to expand...


As said, the cheap one is not very good at all, (not unlike a lot of stuff from that source) not only is it not of welded gas tight construction but introduces two joints which should be avoided if practical and if not practiacl should be well made and gas tight.
 
Thanks for your advice chaps, fitted the silencer today and it has made a huge difference to the noise, much quieter and liveable with now, well worth the cost and effort.

Happy Christmas to you all.

Rob
 
You must log in or register to reply here.

Other threads that may be of interest

UK-WOOZY
Autoterm 4kw heater was blowing smoke out into the cabins
2
Replies
25
Views
916
Babylon
B

Share this page

Top