Mike Adams

It is quite a strange fact that most narrow boat owners tend to over estimate the draught of their vessels. I owned for something like 25 years a narrow beam tug that initially drew 3ft 7inches until I re-engined it and managed to get it down to 3ft 4 inches. We traveled a high proportion of the waterways and yes we had problems but they were usually caused by an unexpected low level or an obstruction and were only once totally defeated by an obstruction. My current boat is about 2ft 6inches which is probably ideal for handling and it is bliss to never even think about going aground. The reason most people go aground is because they are going too fast and get out of the channel.

Yes but it was built for 'West Country' Thames barges which were large but had a very very shallow draught and could make their way up the Thames either under sail for by being pulled from the bank before there were all those fancy pound locks on the Thames.

Where did you get your replacement heads? I thought the supply had all but dried up. I would do a compression test to make sure you have some first.

I nearly bought a please steamer in Germany with one fitted. Seemed to go OK but I don't think it would work in a narrow boat as it seemed to create a lot of vibration in what was a larger boat than an NB.

Pulling a boat from the bank is very different from driving a boat with a propeller. When you are tied up to the bank there is a force on the mooring ropes but no work is being done and no energy used however when going against the stream on a motor boat you need to expend energy just to stand still let alone make progress. It is much more efficient being towed from the bank. This was often the case on continental rivers where a low powered tug connected to chain on the riverbed could pull a string of barges against the current even if only slowly. The work required to move a boat towed by a horse is more interesting because the horse just standing there is not in theory using any energy. My Grandfather used to work as a waterman on the Thames above Teddington with a horse towing timber barges to Kingston and beyond and he only had one horse to tow a lighter. The actual speed of the current near the bank can vary a lot but usually much less than that in the centre. When I go upstream when the Thames is in flood I stick as close to the bank as I can but you do need some power to get through certain bridges which is probably the limiting factor for a narrowboat. I seem to remember the original way they calculated the power of a horse was with a horse gin lifting a weight but I don't think it was necessarily the maximum power of a horse. I am sure a racehorse produces more than 1hp in a race.

New hoses arrived so will have to see if they leak. My daughter once had the boat and phoned up to say the engine was going but no propulsion, turned out she had a rope fender between the prop and the uxter plate but operating the controls the PRV must just cut in without any noticeable difference from normal except the prop wasn't going around.

Your speed on the Thames is most likely to be limited by the hull shape and waterline length. The shape of the stern/swim will limit the power input that can be applied to increase the speed without causing excessive wash and power consumption. 40Hp would be fine with a 2:1 reduction gearbox. Unless you have a very short run ( less than 6ft) in to the propeller you should be able to cope with most river conditions. You don't need 40Hp to achieve this performance but because of modern engine design with higher speed/less cylinder capacity anything smaller is going to sound irritating screaming away all day.

Very low, in fact it only gets warm to the touch after running all day. I fitted a temperature sensor with a gauge to show the oil temperature but it never gets hot enough to register on the gauge. I know the bent axis pumps/motors are very efficient and the hoses run almost the whole length of the boat so I guess most of the heat generated is dissipated. I did think about fitting another prv in between the two lines with a relief line back to the tank but I will try the replacement hoses first. I have also adjusted the rate on the engine throttle remote control lever so that it has to move further for the same acceleration of the engine so as to slow down any rapid change of direction on the single lever control.

Thanks for the comments. I have now looked back at the original fitting instructions from 1987 where it says ' The main feed and return hoses should be of multi wire spiral construction and capable of withstanding a burst pressure of 16000 psi or 1100 bar or solid pipework to BS3602' but it doesn't give any specification for the hose. This seems very high the ones I have ordered as replacement are working pressure of 4800 psi so maybe I need to rethink these. I haven't found out yet the relationship between working and burst pressure but I have never had any bulging hoses.

As one who was involved with the restoration of both the Kennet and Avon and Basingstoke Canal I can say that the profiles of these canals were really only designed for the slow passage of a horse drawn wide beam barge and are not suitable for 14ft square section boxes propelled by a large diesel engine. I would say that generally the profile hasn't changed that much. Just because a boat can fit the theoretical dimensions does not mean that it is a suitable vessel for the canal.

Both the pump and motor are interchangeable, they are both bent axis devices so can act as pump or motor. The existing PRV is between the the pump on the engine and the control valve. So if you turn the propeller the motor on the shaft acts as a pump. So if the shaft carries on for bit after you change direction the two pumps(one being the motor)could be opposing each other for a short time possibly? I obtained the pressure rating from the speed ,hp and pump/motor characteristics. I may be taking rubbish here as I not by any means a hydraulics expert.

I thought of buying some of those, or at least something similar but as the pressure can go up to 4000psi on 3/4 hose I wasn't sure if they would handle it. On further reflection it is the two fittings on the output of the control valve going to the stern and drive motor that are leaking the worst perhaps going too quickly from ahead to astern and vice versa causes a bit of a pressure surge at that point if the propshaft has some inertia the two pumps could be operating against each other for a short time. I think the PRV is on the other side of the control valve. Perhaps I need another PRV in the circuit?

My main gripe with them is that they are primary houseboats yet they sign themselves up as continuous cruisers of which they are neither continuously moving or using the canals for a leisure experience. They are often left unattended for days and sometimes weeks in the most awkward positions often next to bridgeholes so blocking the line of sight. Since they displace nearly twice the volume of water than a narrow boat they cause much more erosion to the bank unless they travel at horse drawn speed and no one can pass. They are also built like boxes and tend to cut into the profile the canal bed. Nearly all the the working boats in the south were timber and round bilge so much more sympathetic to the waterway. All in all I would say they are a very bad thing down here in the south.

I don't think there is any canal south of Nottingham that is suitable for Wide (12 to14ft) boats except around London. We just managed to pass one on a canal down south today but their progress was to my mind very slow at 2MPH. The OP might have all the time is the world to hold up traffic but most of us don't. What people fail to remember is that on these wide beam canals and rivers such as the Wey, Basingstoke and Kennet and Avon there were very few wide commercial boats and they generally knew where they all were and could work together where the channel was narrow. OK the GU was widened in the 1930's but not the channel above Berko and wide boats were never a success. Personally I hate the things, they are generally very ugly, slow and defeat the whole idea of pleasure boating and make everyone else fed up with them. If people want to live in a tin box why can't they buy a mobile home and a small boat for cruising.

Thanks for the comments. I think I will order a pair of new hoses as I don't fancy the idea of one coming apart!

When I replaced my engine some 4 years ago (it has a hydraulic drive) I needed to replace/extend some of hydraulic hoses. It has all been fine but this year I noticed two of the new made up hoses have started to weep at the crimped part of the terminations and not at the screw on joint while the other pair, which were purchased from a different supplier, are fine. Both sets are subject to the same working pressure.The hoses are from different manufacturers but the same working pressure/spec but the ones that are leaking don't seem to be crimped quite as hard. I guess the only option is to replace them. Unfortunately I purchased them through Ebay. Any recommendations for a good supplier or brand or could they be re-crimped now? The pair that have failed are not subject to any movement are not subject to any movement whilst the other pair that are good connect the static control valve to the engine pump which is subject to engine vibration.

I would say everything is fine. Mine holds a bit of pressure even a couple of weeks after it has been run which wouldn’t happen if it had a leak or a head gasket problem.

Sorry I didn't make it clear. According to the wiring diagram you can opt for a 70A or 110A Alternator when ordering. The wiring loom can cope with either.

I think is means the White cable which is not used on the 70A alternator but is on the 11oA alternator should be insulated and tied back to the loom. White is live (+12v) with the ignition in the run position. Your alternator gets its energised through the indicator lamp on the panel so does not need the live to get energised. Hope this helps

I think the JD 3,4 and 6 cylinder versions are about as near to a traditional engine you can get although I think the latest are common rail which you really don't want on a boat. They are easy to work on, spares are easy to get anywhere and easy to maintain. They have wet liners too so quite an easy job to change the liners and pistons.

I believe the problem you are having with the JD injectors is due to the modification by Beta to make the engine run slower. They are designed to tick over at 800rpm. When I was running 2 JD's in boat they ran for over 10 years without making any smoke at all. I don't know the situation now but it was possible to pick up the injectors quite cheap from the US.

I doubt the current alternator will last very long with your set up. You need a larger alternator but that is only part of the problem. Depends on the engine, possible location of the alternator and the drive belt. You will probably need a multi ribbed pulley and if you require it to charge at tickover a different ratio. Trying to take too much current at low alternator speed will probably overload and overheat the alternator. One option is to fit a watercooled alternator or a second alternator but this depends on the engine. I ended up fitting two to ensure you get enough charge if, for example you are locking through a long flight all day.

I have just pulled the thermostat from my spare(almost new) engine in the workshop which I am sure is factory. Hope this helps. It has a rubber seal at the top. You should see the top open in boiling water or heat it up slowly in a saucepan and you should see it open before the water boils. You can see the quality of the jap oem stat they almost never fail in my experience

Just one thing I forgot to mention and that is there were 2 different versions of the engine and I believe HMI may have used both one is the 4LE1 and the other 4LE2 ,one is direct injection and the other is indirect and although the same capacity use different cylinder heads and May use a different thermostat.

I have a spare engine and will have a look at its thermostat and the weekend but I have a feeling it different to a standard automotive one in that it seals in two places. The cooling system (skin tank)is designed to dissipate at least the maximum waste energy of the engine which is approximately equal to the power output of the engine 40kw. At say tickover the skin tank will take all the waste heat away as it is produced and the engine should only get slightly warm and it will maintain this equilibrium indefinitely. It is extremely important to have the correct thermostat on a modern engine as it is designed both to reach and maintain the correct temperature and maintain thermal balance across the engine and avoid any thermal stress. Running without a thermostat in my opinion could cause head gasket failure and worse. Do you still have the old thermostat ? if so check if it has a rubber ring seal at the base.