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kingswood

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Having taken a few old engines on rivers i have a few standard precautions.

 

firstly never take the engine out of its comfort zone, either by duration of running or workload.

going downstream i run below normal rpms, going upstream at normal rpms. The engine then is at canal ‘stress’

 

before going on river i check everything twice, including bolt tightness of relevant bits.

i look round engine in locks.

 

if going upstream for long periods i wind back every 20 mins to let things cool.

 

with a modern watercooled engine i wouldnt be so bothered, but aircooled listers running at higher than normal revs can get a bit hot if the cooling fins are dirty.

 

anchor and lifejacket..

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Why would any engine go out of its comfort zone going downstream? You've only got to be moving fast enough to have enough water flowing over the rudder to steer, with maybe the occasional burst of power to get you off the river and into a lock cut for example. 

 

Going upstream ultimately you've either got enough power to make headway against the current without overheating or you haven't, and there's not really much you can do about it if you haven't.

Edited by blackrose
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1 hour ago, roland elsdon said:

Having taken a few old engines on rivers i have a few standard precautions.

 

firstly never take the engine out of its comfort zone, either by duration of running or workload.

going downstream i run below normal rpms, going upstream at normal rpms. The engine then is at canal ‘stress’

 

before going on river i check everything twice, including bolt tightness of relevant bits.

i look round engine in locks.

 

if going upstream for long periods i wind back every 20 mins to let things cool.

 

with a modern watercooled engine i wouldnt be so bothered, but aircooled listers running at higher than normal revs can get a bit hot if the cooling fins are dirty.

 

anchor and lifejacket..

I am confused - not entirely unusual for me.

 

Does this mean that you also wind back every 20 mins on the canal. If not, what is the difference?

 

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Just now, blackrose said:

The difference is that you're not generally going against a current on a canal

Yes but are you not still interspersing periods of normal RPM with periods of winding back? Obviously I agree that on a river you will make less headway at normal RPM but that is what Roland uses nevertheless.

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31 minutes ago, frahkn said:

I am confused - not entirely unusual for me.

 

Does this mean that you also wind back every 20 mins on the canal. If not, what is the difference?

 

The straight answer is 'yes'. How often on a canal do you cruise flat out for more than a mile without winding back?

 

You naturally take the engine revs down regularly for things like moored boats, bridges, locks and blind bends. On a river - and certainly on the Severn as asked by the OP - without deliberately reducing revs you will run the engine longer at full cruising speed than you ever do on a canal. Roland's experience certainly makes sense to me based on what I find and my engine is water cooled.

 

JP

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Sorry yes by winding back on long stretches i am replicating what occurs by default on the canal. Our boat is deep draught and so gets wound back passing moored boats and in bridge holes. Temperatures can rise quite rapidly upstream on a river and marginal cooling systems come under stress. Some of those river reaches are long.

 

 

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Mostly depends on the water flow, middle of summer generally not much flow, no bother at all, middle of winter even the ducks stay away.  I would always have an anchor of some sort, I've got all the proper gear - never used it but I like to know its there.

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10 hours ago, Captain Pegg said:

The straight answer is 'yes'. How often on a canal do you cruise flat out for more than a mile without winding back?

 

You naturally take the engine revs down regularly for things like moored boats, bridges, locks and blind bends. On a river - and certainly on the Severn as asked by the OP - without deliberately reducing revs you will run the engine longer at full cruising speed than you ever do on a canal. Roland's experience certainly makes sense to me based on what I find and my engine is water cooled.

 

JP

Fine, that explains it. Thanks.

 

In answer to your question - I've never been flat out in forward gear in more than 40 years.

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11 hours ago, blackrose said:

The difference is that you're not generally going against a current on a canal

Yep.  Going up the river Severn there can be a 2mph flow down stream.  At ‘normal’ revs on a canal you will be going at 3mph, on a river against the flow you will have a ground speed of 1mph.  Going from Gloucester to Worcester is not quite 30miles which at normal canal revs against a 2mph flow will take 30 hours.  So you need to up the revs  to give a water speed of about 6mph or more if you can.........

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12 hours ago, blackrose said:

Why would any engine go out of its comfort zone going downstream? You've only got to be moving fast enough to have enough water flowing over the rudder to steer, with maybe the occasional burst of power to get you off the river and into a lock cut for example. 

 

Going upstream ultimately you've either got enough power to make headway against the current without overheating or you haven't, and there's not really much you can do about it if you haven't.

For me, if the river is flowing so fast I have to run at higher than canal speed I dont want to be there. Lets face it, if its flowing at 1 1/2 Mph you would still make 2 1/2 Mph against it.

59 minutes ago, Chewbacka said:

Yep.  Going up the river Severn there can be a 2mph flow down stream.  At ‘normal’ revs on a canal you will be going at 3mph, on a river against the flow you will have a ground speed of 1mph.  Going from Gloucester to Worcester is not quite 30miles which at normal canal revs against a 2mph flow will take 30 hours.  So you need to up the revs  to give a water speed of about 6mph or more if you can.........

I am not sure I can do 6 Mph but never had a problem

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6 hours ago, roland elsdon said:

Sorry yes by winding back on long stretches i am replicating what occurs by default on the canal. Our boat is deep draught and so gets wound back passing moored boats and in bridge holes. Temperatures can rise quite rapidly upstream on a river and marginal cooling systems come under stress. Some of those river reaches are long.

 

 

In the Autumn we came up from Gloucester to Harford and the time between Tewkesbury junction and Diglis was about 3.25 hours, so quite a long time without a rest for the engine. We were, however doing so with a new Beta 43 which is within its comfort zone but I give the time so you can assess for yourself. There are some stretches on the Avon which are longer than the pounds on some canals but not wholly exceptional. There are few lengths on the Avon where you would not encounter some reason for slowing down, at least a bit fairly often.

 

One point I would add to the previous advice is, if single handing, let someone know your 'flight plan' and can check that you have arrived. That's independent of your engine! The main thing affects most boats apart from some of the super-barges on the Severn, is the flow rate - and note that it is distinct from river height. The two sort of correlate but not always. As I understand it, heavy fall in the catchment area can dump a lot of water downstream which initially increases the flow rate. After a while the amount of water coming down exceeds the capacity of the navigation to dispose of it, especially over the main weirs, and so the rive level rises. Similarly, once the rain has stopped, the flow slows down but it takes a while for the excess to run away and so the level lags the flow (unless someone has a different explanation!) However, it is a managed water course so the actions of lock keepers and EA in general will have an impact, hoping to mitigate the excess in change to either flow or level (it is level that bothers more people than rate as that is what determines when flooding occurs)

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13 hours ago, blackrose said:

The difference is that you're not generally going against a current on a canal

You aren't,  unless on the Llangollen,  however, you are battling the draw of water from fore to aft, especially on a shallow narrow canal. This limits forwards progress a lot, and more the higher your revs go. I find that Old Friends can achieve much higher river speeds with a lovely big depth of water around her.

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2 hours ago, frahkn said:

Fine, that explains it. Thanks.

 

In answer to your question - I've never been flat out in forward gear in more than 40 years.

Ah yes, flat out wasn't the best description on my part.

 

9 minutes ago, matty40s said:

You aren't,  unless on the Llangollen,  however, you are battling the draw of water from fore to aft, especially on a shallow narrow canal. This limits forwards progress a lot, and more the higher your revs go. I find that Old Friends can achieve much higher river speeds with a lovely big depth of water around her.

One reason why you don't necessarily need higher revs on a river. I find with the bigger channel, broader horizons and effects of flow it isn't necessarily obvious how fast you are moving over the ground until you enter a lock cut.

 

JP

 

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Amongst all this discussion, when travelling downstream, as the Capt says, you're not always aware of the speed you are travelling, and what effect this has on steering. You will travel a lot further in a manoeuvre than on a canal, and you also need to be aware of this when stopping, so you know you're engine has enough in reserve to achieve your objectives. 

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Wallingford bridge on the Thames, going upstream in a flood.  Engine flat out, counting the bricks as we crawled through.  No idea how hot the Lister got.

Going downstream on Kennet in Reading, very fast current - stern first, engine going just enough to give control.  Any trouble, just wind speed on and you stop.  Coming out onto Thames was interesting, going broadside at several mph.

If you are not used to rivers, keep away in a flood.  Lives have been lost.

wreck.JPG

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I can't stress enough how important it is on a river to have your anchor rigged and ready to deploy in an emergency.  This means having enough chain and warp for the depth of water.  If you are on a narrow river and it would not be possible to turn the boat to head upstream then consider rigging the anchor at the back of the boat.

 

It's a good idea to make the warp fast to two places in case the first one fails.  T studs have been known to break.

 

Nick

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38 minutes ago, Theo said:

I can't stress enough how important it is on a river to have your anchor rigged and ready to deploy in an emergency.  This means having enough chain and warp for the depth of water.  If you are on a narrow river and it would not be possible to turn the boat to head upstream then consider rigging the anchor at the back of the boat.

 

It's a good idea to make the warp fast to two places in case the first one fails.  T studs have been known to break.

 

Nick

It is a good idea NOT to use the T-stud full stop, it will not survive a big snatch.....speshly if its a brass one!!

Get a proper anchor point bolted and welded in somewhere across more than one piece of thick steel. Sod the paint the chain or rope might take off if its low down - you are saving your boat.

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Possibly two anchors, one each end.  Take advice as to what type of anchor.  I have to confess that our anchor was a 56lb weight - not really suitable for a loaded boat in a flood. 

Also, make sure your fuel tank is full and oil checked.  Have a map so that you know where the weirs are, not all rivers are as well signed as the Thames, and the weirs may not be obvious.

Having said all that, don't be put off rivers, the only difference is that the water is moving.  They are much more fun than ditch-crawling.

Jag2.jpg

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3 hours ago, Graham Davis said:

I wonder how many hire boats safely navigate the Severn and Avon without an anchor? I know we did it several times.

It only really matters when the engine fails and you are near a weir. 

Even the Oxford Canal has two river sections and they can be nasty when it floods, which it does.  Lousy photo at Aynho Weir.  

Aynho.jpg

Edited by Chris Williams
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