Eberspacher Exhaust Silencer Installation

dje67

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Just bought one of these for £30 on ebay to try and reduce the exhaust noise on my Eber.

http://www.ebay.co.uk/itm/111018885347

Even although it was overseas (from UK) it arrived in 2 weeks, over Xmas - quite impressed!

However, it didn't come with any installation instructions. My exhaust currently leaves the Eber and heads upwards before swan-necking back down onto the skin fitting. Where should the silencer be fitted so that it doesn't gather condensate. I think I'll put it in the vertical section leading down to the skin fitting, if there's space, but wondered if that's the best place to put it or whether it needs to be mounted horizontally. Wherever it ends-up, it'll be lagged to keep the heat in, so maybe condensate won't be an issue as it'll boil off?

Thoughts?
 
Mine is mounted about 2/3 along the exhaust line, horizontally, at the highest point. Installed by others, so cannot say if this is necessarily correct. Works fine tho!
 
Just bought one of these for £30 on ebay to try and reduce the exhaust noise on my Eber.

http://www.ebay.co.uk/itm/111018885347

Even although it was overseas (from UK) it arrived in 2 weeks, over Xmas - quite impressed!

However, it didn't come with any installation instructions. My exhaust currently leaves the Eber and heads upwards before swan-necking back down onto the skin fitting. Where should the silencer be fitted so that it doesn't gather condensate. I think I'll put it in the vertical section leading down to the skin fitting, if there's space, but wondered if that's the best place to put it or whether it needs to be mounted horizontally. Wherever it ends-up, it'll be lagged to keep the heat in, so maybe condensate won't be an issue as it'll boil off?

Thoughts?

Firstly, like most of his stuff, it is not really a marine gas tight silencer, the proper part comes welded to the exhaust tube so as not to introduce any more user made joints than absolutely necessary. Now that's out of the way, fit it as close to the heater as practical, the orientation is not important, as it is what it is ensure that it is not in the accommodation areas and the air for recirculation is not drawn from the same space where it is e.g. in a locker. Make sure any cuts in the existing exhaust line are at 90⁰ and use proper size and quality clamps and exhaust assembly compound on the joints when fitting. Condensation shouldn't be an issue except on very long runs.
 
Firstly, like most of his stuff, it is not really a marine gas tight silencer, the proper part comes welded to the exhaust tube so as not to introduce any more user made joints than absolutely necessary. Now that's out of the way, fit it as close to the heater as practical, the orientation is not important, as it is what it is ensure that it is not in the accommodation areas and the air for recirculation is not drawn from the same space where it is e.g. in a locker. Make sure any cuts in the existing exhaust line are at 90⁰ and use proper size and quality clamps and exhaust assembly compound on the joints when fitting. Condensation shouldn't be an issue except on very long runs.

That item looked substantially more 'fit for purpose' than the riveted or spot welded cheapo versions you see ( which would be lethal) if mounted inside, why is it called a 'marine airtight' silencer then?
I have found that dealer gives excellent service and good prices.
 
That item looked substantially more 'fit for purpose' than the riveted or spot welded cheapo versions you see ( which would be lethal) if mounted inside, why is it called a 'marine airtight' silencer then?

As I explained, because it introduces two more user made joints and therefore doubling potential for leaks . It has a better chance than the pressed steel vehicle ones though which have no place on a boat except in the engine room using a coolant based heater.
I have found that dealer gives excellent service and good prices.

There are those that would strongly disagree, particularly those who bought outside the protection that Ebay gives. If you PM me an email address I can let you have a screen shot of an ebay message exchange where he admits a heater is not as it is described. That said I have had decent service for small hard to source heater specific plugs, but that is all I would risk after the last close shave.
 
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ensure that it is not in the accommodation areas and the air for recirculation is not drawn from the same space where it is e.g. in a locker.

Our "professionally" installed Eber draws circulation air from the same space that the unit is mounted in. From your comments, I assume this is not good practice. We have a yacht and the heater is mounted in a very hard to access location underneathe the bathing platform at the stern. The exhaust pipe rises up from the heater and exits quite high up through the transom. See pic below. In such circumstances, where do you suggest we should draw the circulation air from? Thanks.

View attachment 39002
 
Our "professionally" installed Eber draws circulation air from the same space that the unit is mounted in. From your comments, I assume this is not good practice. We have a yacht and the heater is mounted in a very hard to access location underneathe the bathing platform at the stern. The exhaust pipe rises up from the heater and exits quite high up through the transom. See pic below. In such circumstances, where do you suggest we should draw the circulation air from? Thanks.

View attachment 39002

Trunk to the heater inlet from any convenient place in the cockpit and check it's integraty every so often, with a well installed relatively new system these things shouldn't be a worry but down the line or for any reason a leak occurs I would not want to be responsible for it, before anybody accuses me of scaremongering, we all now that leaks can and do happen on heater exhausts, of course every boat is equipped with a CO alarm too so all is safe really.
 
Ah. What happens if we get a green one back in the cockpit? Seawater down into the heater? Isn't that why the exhaust is high up on the transom and has the exhaust pipe coming down onto the thru hull fitting?

Could I use the shrouded fitting on the port side as the inlet? Its currently used as the outlet for the thermostatically controlled extract fan from the engine space.

FYI, we have 3 CO2 alarms and a carbon monoxide alarm on board.
 
I ordered the same on but it was faulty. Please double check yours by sealing one end and blow down it. Mine leaked like a sieve around the tube and I returned it. I hope the seller now checks them as mine was very dangerous especially if the intake air to be heated is taken from the same space.

Let us know if yours leaks please
 
I quite like the exhaust sound from our Webasto (when it's not broken down). The thing I don't like is the ticking fuel pump. I've got some ideas to bodge a low-noise mount but why don't they make a proprietary one?
 
I quite like the exhaust sound from our Webasto (when it's not broken down). The thing I don't like is the ticking fuel pump. I've got some ideas to bodge a low-noise mount but why don't they make a proprietary one?

They do and it should be mounted on said rubber mount.

Do you have copper pipe connected directly to the pump? I removed and added a short loop of plastic at each side and the tick noise vanished. It seems most of it was structure born and transmitted by the copper.

I don't think you can do the above if you use your boat on inland water ways however as they require all copper.

Steve
 
yeah - I have it mounted on that but isn't really effective. Copper does connect to the pump with a short section of rubber fuel hose so might extend that with some plastic. Thanks for the tip.

On Windermere so no scrutiny fortunately!
 
They make one for Mercedes which I have been experimenting with recently, fitted to two boats and a motor home with success and on my test bed with equal success, trouble is they are difficult to source. They are more of a hanger than a mount but you do need to use rubber joints in the line if the rest is copper. Using BS7840 hose satisfies the B.S.S. if you need one. Half the battle is what you mount the whole thing on though, the more solid and sound absorbing the better. For non B.S.S, liable boats I still prefer to use the old Tygon ™ stuff Webo used to issue in kits which makes installs easier and quieter.
 
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