Advice on an Eber' exhaust silencer please

[Ian_Edwards]

I'm renewing the exhaust on my Eber Hydronic 10, and plan to fit a silencer.

The system uses a 30 mm exhaust pipe and it need to be about 2.5m long. It also needs to be made of SS.

After searching with Google for a while, I've only found two 30mm silencers:

http://www.melloronline.co.uk/Vehic...1QDZCX3FsUTQoRJWgacrO8ZjHKoBAYxYH1hoCt__w_wcB

Which seems to be some sort of distributed Silencer, comes in 2m lengths and costs a hefty £130.80 and at 2m, it's not really long enough.

and

http://www.hallselectrical.co.uk/exh-30mm-marine-silencer.html

No picture, but it seems likely to be some sort of box shaped unit at £61.09

Anyone know of any other sources for 30mm Silencers for an Eber?

If I go for the box type, is it better to fit it close the the heater or close to the skin fitting? I can't fit it in the middle there is a locker shelf in the way

Should I try and insulate the silencer? if so, what the best material to use, a kitchen fire blanket?

Do I really need to fit a drain to the exhaust system? The original exhaust system didn't have one and there's no sign of corrosion in the 8 year old exhaust pipe.

There needs to be a fairly sharp ~145 degree bend at the top of the exhaust pipe to get the pipe from the near vertical rise up the transom and into the skin fitting (this section with a tight bend in it failed, just before the skin fitting). Is there a better way of getting a 145 deg bend into the pipe?

I'll phone the suppliers for more info' in the morning, but any help and advice from the forum would be much appreciated.

 

[GeorgeLlewellin]

You are probably aware that the silencers for Eberspachers fitted to shore based unites are not necessarily completely sealed and can leak gasses including carbon monoxide.

Your first link looks interesting, the only problem (as always) is the price.

Good luck, please post here to let us know how you get on. George.

 

[David2452]

The first one is the ideal unit for your install, regardless of diamiter they come in 2m LOA as generally speaking that is the maximum exhaust length recommended when a silencer is included, hower if needs absolutely must then a short extention using a well sealed joint will be needed, preferably at the skin fitting end. With a hydronic however, the normal rules of using a sealed system can be bent a little as no circulated heating air is present to carry exhaust products around the boat. So, if the unit is installed where no gas can enter the accomodation (in the engine bay for example) then a standard silencer with well sealed joints and 30mm flexible exhaust can be used. Fit the silencer as close as practical the the boiler and use exhaust insulation wrap on the pipe and silencer, secure with siezing wire of better slill, stainless tie wraps.

I'm renewing the exhaust on my Eber Hydronic 10, and plan to fit a silencer.

The system uses a 30 mm exhaust pipe and it need to be about 2.5m long. It also needs to be made of SS.

After searching with Google for a while, I've only found two 30mm silencers:

http://www.melloronline.co.uk/Vehic...1QDZCX3FsUTQoRJWgacrO8ZjHKoBAYxYH1hoCt__w_wcB

Which seems to be some sort of distributed Silencer, comes in 2m lengths and costs a hefty £130.80 and at 2m, it's not really long enough.

and

http://www.hallselectrical.co.uk/exh-30mm-marine-silencer.html

No picture, but it seems likely to be some sort of box shaped unit at £61.09

Anyone know of any other sources for 30mm Silencers for an Eber?

If I go for the box type, is it better to fit it close the the heater or close to the skin fitting? I can't fit it in the middle there is a locker shelf in the way

Should I try and insulate the silencer? if so, what the best material to use, a kitchen fire blanket?

Do I really need to fit a drain to the exhaust system? The original exhaust system didn't have one and there's no sign of corrosion in the 8 year old exhaust pipe.

There needs to be a fairly sharp ~145 degree bend at the top of the exhaust pipe to get the pipe from the near vertical rise up the transom and into the skin fitting (this section with a tight bend in it failed, just before the skin fitting). Is there a better way of getting a 145 deg bend into the pipe?

I'll phone the suppliers for more info' in the morning, but any help and advice from the forum would be much appreciated.

 

[Ian_Edwards]

Thanks for the replies.

I wasn't aware that the standard silencers could leak, do you think that applies to the ones marketed as "Marine Silencers"?

The Eber is in the stern of the boat, mounted low down on the inside of the transom and on centreline of the boat, the skin fitting is high up on the starboard side of the transom, effectively under the side deck. I doubt that the lockers are gas tight, so I'll have to make sure that whatever I use is gas tight.

If I go for the continuous silencer in the first link, do I still need to insulate it?

I could reduce the length required by using an 90 degree elbow at the heater end of the exhaust pipe, the exhaust outlet point down. The elbow would save the extra length of exhaust pipe required to make the bend. Is there any down side to using an elbow directly onto the Hydronic 10?

And do I need a drain pipe to clear the condensation? As noted in the OP the system as supplied by Southerly didn't have one.

 

[David2452]

In a run of that length I would usually install a condensate drain at the lowest point, good practise rather than essential, particularly if the exhaust is well lagged, lagging is there for two reasons, 1 to reduce chance of things getting singed (including you) 2: to keep the exhaust gas and pipe hot thus reducing condensation so yes do lag it. At the length you are using I would restrict any elbow use to a proper swept one and not the 90 degree butt welded type.

 

[pcatterall]

David is the 'main man' for advice!
Some silencers ( usually the 'flat' £20 ebay ones are just riveted and will leak fumes into your boat.
I suggest that condensation will be an issue.
A 90 degree bend would be even more problematic than the extra pipe.