Exhaust Gardners

[mark99]

Our exhaust contains a expansion box/silencer (may be incorrect term but looks like a standard vehicle type) which I enclosed with brass guard.

 

 

 

I must say two boats on our mooring which have Gardners (2lW and 3LW) just have a 50mm pipe right up to roof... and to be honest they sound much better/growlier than mine without being antisocial!

 

I'm thinking about swapping out to straight exhaust or possibly just adding a simple section of 100mm pipe as an expansion box without silencer.

 

Any thoughts?

[furnessvale]

Our exhaust contains a expansion box/silencer (may be incorrect term but looks like a standard vehicle type) which I enclosed with brass guard.

 

 

 

I must say two boats on our mooring which have Gardners (2lW and 3LW) just have a 50mm pipe right up to roof... and to be honest they sound much better/growlier than mine without being antisocial!

 

I'm thinking about swapping out to straight exhaust or possibly just adding a simple section of 100mm pipe as an expansion box without silencer.

 

Any thoughts?

My 2LW is so quiet I suspect it may be one of those "hospital" types.

 

I am fed up of catching anglers unaware of my approach and I am considering a "bit" more woof!

 

George ex nb Alton retired

[steamraiser2]

We often get exhaust silencers made up for client's boats. MIJ exhausts can make up a stainless steel silencer to size at a really good price. Their "mid sport" noise grade gives a great balance between a good note but without an irritating noise level. Boy racer technology to be admired for once.

 

incidentally a 50 mm bore pipe is a little small for a Gardner. 75mm is a better bet.

[MtB]

I have a 3" exhaust on my K1, which was a little too 'barky' when first installed.

 

I initially added a silencer which made it virtually silent (quelle suprise!)

 

I remove the silencer and had a 3.9kG gas bottle welded into it instead. perfect noise level. People can hear the quiet chuffing of my boat coming and a constant stream of compliments about how nice it sounds!

[David Mack]

The National 2DM on Fulbourne has a silencer fitted, and doesn't quite make the right noise for a slow running 2-pot engine. But if you lift the exhaust chimney a couple of inches above the roof fitting it gives a lovely resonant exhaust note. I'm thinking a making up an exhaust pipe with 'windows' in the bottom to make the better sound all the time!

[mark99]

We often get exhaust silencers made up for client's boats. MIJ exhausts can make up a stainless steel silencer to size at a really good price. Their "mid sport" noise grade gives a great balance between a good note but without an irritating noise level. Boy racer technology to be admired for once.

 

incidentally a 50 mm bore pipe is a little small for a Gardner. 75mm is a better bet.

 

Thanks - just the sort of info I was after. The boat next to us pulled away yesterday - same engine as ours - and it sounded like a JP2 instead of the 2LW.

[richardf]

Have a chat with TW Marine - they understand silencers, back pressure and the like. They will sell you an expansion box - without baffles. It might just be what you are looking for

[DHutch]

Not something I have played with much, but I expect an expansion box/tube alone will do what's wanted, but without knowing exactly how loud you want its trial and error really. Your after seeing the sound, while knocking the harshness out of it. If your lucky you will get smoke rings....

 

 

Daniel

[matty40s]

 

Mine was originally like this, but the spring tube has now been replaced with another 1/4" narrower- and it sounds bloomin lovely, and blows smoke rings.

[LEO]

Mark,

 

How does this sound?, 'Titch' and normal pipe....................it lasts about 5 mins.....

 

 

M

[mark99]

Mike sounds good. difficult to tell from speakers. Looks like a short silencer/muffler in situ. I'm raiding my pipe stores and will knock up various types of exhaust until I got it right. Will try 80mm, 50mm and possibly 100mm.

[by'eck]

 

Thanks - just the sort of info I was after. The boat next to us pulled away yesterday - same engine as ours - and it sounded like a JP2 instead of the 2LW.

 

Must have got it right then

[Alan Saunders]

My 2LW is so quiet I suspect it may be one of those "hospital" types.

 

I am fed up of catching anglers unaware of my approach and I am considering a "bit" more woof!

 

George ex nb Alton retired

For me a major bonus of the Gardner is how quiet it is! With a large silencer a towpath walker will smell the exhaust fumes before they hear the noise of the engine. At tickover it is inaudible at a boat's length, 70'. It is possible to hold a conversation in the engine room.

 

There is no way that I would want to make it louder. I can run my engine between 8pm and 8am without disturbing anyone.

 

Alan

[mark99]

I removed silencer and replaced for a trial with a 1m long 4" thin flexible steel pipe (B+Q sell them) just to hear.

 

Surprisingly hardly any loudness difference however there is a deeper bass tone. It gets better as the engine works a bit harder too. Silencer is now back on as the 4" one was a temporary trial.

 

So I'll now get a 3" jobbie with 3"/2" reducers and union made up as a permanent straight exhaust.

 

ETA photo of temp exhaust.

 

Edited July 27, 2015 by mark99

[fretman]

Yes , have to agree , bass tone is that much better, that's what I have on my 3LW, just a pipe out,, sounds good to me.

[Cloudinspector]

Here's ours. 3" pipe and silencer.

I'd be interested to hear what yours sounds like without the silencer.

 

 

[dave moore]

Stuart Harper of Barnowl Narrowboats had a straight pipe on his 2LW in a Norton Canes shell. I found its percussive crack a bit hard on my ears, perhaps it's me not the sound. Straight pipes were often favoured by some young boatmen that I knew in the 60s, one Armstrong Siddeley AS2 was especially strident! I suppose it's on a par with today's hot hatchback with a farty big bore exhaust.

 

Cheers

 

Dave

[Athy]

 

Mine was originally like this, but the spring tube has now been replaced with another 1/4" narrower- and it sounds bloomin lovely, and blows smoke rings.

That's the rare 2L2B model isn't it?

 

The B stands for "bling" of course.

[mark99]

Here's ours. 3" pipe and silencer.

I'd be interested to hear what yours sounds like without the silencer.

 

 

 

 

Again it's hard to tell from speakers although I have good ones..... but that's the sound I'm after. Bassy. I'll report back once I've stopped twiddling about (3" and 2" ones now to be tried when I get the time).

[ChimneyChain]

Really?? has no one got anything else better to do then worry about getting just the right sound out of the engine. You lot need to get out more.

 

Darren

[mark99]

Bad day at office CC?

 

Part of the reason to have a slow revving engine apart from the performance is the chugger sound. If you have one that's muffled or choked by a silencer then it defeats it to some extent. Same with my bikes. I tweak them until they sound good. It's what blokes do. Fiddle about with mechanical things and chat.

Edited July 28, 2015 by mark99

[ChimneyChain]

Yes just dropped my bestest guitar!!! Anyway next time your down this way your have to show me yours and I'll show you mine.

 

Darren

[mark99]

You'll hear me coming from Denham Deep.

 

 

 

Yes just dropped my bestest guitar!!! Anyway next time your down this way your have to show me yours and I'll show you mine.

Darren

[mark99]

These are the trial pieces for Saturday. The 3" one is favourite - reduced at both ends to facilitate the existing 2" BSP end connections.

 

 

[MtB]

Hmmm, I think an expansion box would need to be 6" to 8" in diameter to have a noticeable effect on the sound...