dmr

Exactly what is a refurbished battery please???? Is this a bit like the "rebuilt" engines that dodgy London dealers used to sell? I assume it is cleaned on the outside and hopefully flushed and refilled to clear any crud of the bottom. The active material on the plates will still be partly lost! Magnetman raises a very good point. Some level of redundancy is essential for liveaboards and replacement traction cells are not always available next.day delivery! I have seriously considered getting a set of two volt tractions, only having to maintain 6 cells is a bonus. I decided that the weight, height, and lack of redundancy were all negatives and that Trojans where the best compromise. Looking at various specs the cycle life of Tractions is better than Trojans but not by a huge amount! .............Dave

I am getting out of my depth here as I have general knowledge but no Barrus specific knowledge. We need input from Tony as he has hands-on experience of a wide range of engines. A 110mm engine pulley driving a 68mm alternator gives a ratio of 110/68 or about 1.6. This is a bit low. If your engine tickover is (say) 800rpm then the alternator spped is 1280rpm. Most alternators need about 2000 rpm to work. I am not aware of any alternators that actually shut down on a fully charged battery (but could be wrong) but if they did then I would expect them to go into "float" rather than shutting right down so would not activate the light/buzzer. I would be very surprised if Barrus would fit an alternator that did a full shut down. The buzzer should really only sound when something is seriously wrong. My best guess is that your alternator is turning too slowly but I do not know why this problem has just started. Your voltage readings would support this. If you are right "on the edge" then the problem may well appear to come and go ...........Dave

and forgot to say....., in Towpath Talk Fenny Compton marina are using a photo of Our boat taken by Gillie! They took it from the internet (Flickr). Gillie put it there with no copy-write so they are breaking no laws, but an acknowledgement would have been polite! ............Dave

We choose to live on the canal which is a public place, and in some parts a tourist attraction, so can hardly complain if we get our picture taken. Had exited phone call from kids a year or so back to say we were on TV. It was some sort of "location location" thing and we were filmed on the Bridgewater. I never saw a film crew so maybe they did it with quite a long lens? .Only complaint was that we looked like typical boater with me driving and Gillie sat at the front with her feet up.....those who know us will know that this is not how we usually do it! .............Dave

I think you really need to answer two of the above questions Is this a new or existing problem? How big (diameter) is alternator pulley, and corresponding pulley on the engine?. and is the new alternator the same model as the old one?, if not what is it? and does it have the same size pulley as the old one? Do you have anything "big" switched on whilst battery charging? ...........Dave

I think most "proper scopes" won't do mains either unless a 10:1 probe is used?. This little scope looks ok but the sample rate is a bit low (though fine for alternator diagnostics) and It looks like the input connector is not a proper BNC so will not take a proper 10:1 probe. If you poke about on eBay £200 will get an almost "real" scope (Hantek) though these are still based on new fangled technology rather than valves and CRT's, also a bit bigger but still much smaller than the historic stuff. ............Dave

To emphasise wot Nick says, the fundamental chemical reaction is the same, involving lead oxide, lead sulphate, water and sulphuric acid. The calcium or antimony is mostly used to add physical strength to the plates?, though does somehow play a part in the rate of water loss (a Google project for Christmas?) Its this lower water loss that enables the batteries to be sealed/maintenance free Exact acid strength is a manufacturers decision. I think some real proper traction batteries go even stronger than Trojans. I have read that stronger acid can increase internal corrosion, especially in hotter climates. I suspect there is also a downside to weaker acids, probably lower capacity??? ...............Dave I will save this for Christmas day in case all the family stuff proves too much, "sorry about not joining you for Christmas dinner, got an important document to read" Will it answer my question "how much does the SG vary between a well topped up cell and one in urgent need of topping up?" .............Dave

Not sure I have 100% grasped your question, but a possible factor is to ensure that an alternator does not get excited if its not connected, so if the domestic isolator is off and the engine started then the domestic alternator should not be excited or it might self destruct. On the other hand exciting form the domestic bank is not good as it imposes a small residual drain when the engine is off. On our boat a relay is used to excite the domestic alternator from the domestic bank only when the engine ignition is on, dunno if this is standard practice but it makes sense to me. (Actually not sure if its standard practice or practise but I expect the master of spellin an gramma will tell me.) ...........Dave

There is a big bush thing at the end of the lock landing. This not only hides the landing but also makes for a slightly steeper turn in with the possibility of then getting the flow pushing the back out. If there is a strong flow it just might be safer to reverse in, but then we do reverse very well. Watch out for the turn to approach the arched bridge at the bottom of the Oracle, the flow can push the back towards the arch surprisingly hard. ...........Dave

Trojan do put a date code on their batteries, I think its slightly more cryptic than just "2014", but should give the month as well as the year. A bit of googling will find the details. And also do exactly as Nick suggests, if the SG is good then its almost certain the batteries are good. .............Dave

These are good connectors but I am bot sure what a BSS man would say about using 240 volt connectors for 12 volts as there is then the possibility of taking a boat appliance home and plugging it into the mains! I think its ok with the old 5 amp stuff as it is no longer used for mains, though I bet there are a fair few old ladies in old houses still using them. ..............Dave

As the various forum experts have said, the DIN version of the Cigar socket is much better. It has something approaching a proper sprung/ and sliding contact on the centre pin, whilst the cigar plug just sort of gently presses against the end of the socket. The DIN plug/sockets can be rated at up to 16 amps, some are only 8, but I reckon even the 16amps will be getting a bit marginal at 10 amps. A DIN plug is available that will fit both the cigar and DIN sockets with a little plastic adaptor (Google will find all this stuff for you) but a standard Cigar plug will not fit a DIN socket so you will need to buy a few DIN plugs to replace those on everything you have/obtain as they always come with cigar plugs. The better DIN plugs use screw contacts so you don't need to solder. .............Dave

This arrangement does concern me too, I guess the volt drop on the alternator ground to battery negative is usually low so Adverc get away with it. However if there is a shunt in the battery negative there will be a volt drop....but then the Adverc battery monitor puts its shut on the positive side. I assume the Sterling does also sense the battery negative? Then again the Adverc really does most of its stuff towards the end of the charge cycle when the currents and hence volt drops are lower. In my limited experience the isolator makes the volt drop. ....Dave

Our engine is going through a smokey phase at present and it does concern me. As non boaters become more restricted in the use of their motor cars it is only a matter of time before they, and the politicians, turn their interest towards the cut. It is possible to get retro-fit particulate filters but they are expensive and more seriously I doubt if our lazy engines would reach the required exhaust temperatures. Maybe we will need to do what the lumpy water boaters do and discretely pump and gurgle our exhausts into the water. It will be very sad not the see that wonderful plume of black smoke as a vintage engine accelerates its flywheel. ...........Dave

If you are a liveaboard then its difficult, though not impossible, to avoid a bit of a tar stain down the side of the boat. Together with the bags of coal and pile of logs on the roof it is just another sign that you are a liveaboard boat. One boat down here on the K&A has cleverly incorporated it into the paint scheme. .............Dave

Not sure what you mean by offset shafts. The boat dictates the position of the prop and hence height of the shaft at the prop end and hence the height of the back cabin floor. I would not fancy a toothed belt drive etc to lower the prop shaft, not with such a high torque engine. The engine is usually offset sideways a bit to give a better gangway to get past the engine to the back cabin. An offset engine with universal joints in the propshaft works fine. Do note that if using conventional UJ's (Hookes joints) that a bigger offset can be safer than a very small offset! ............Dave

I am not an expert on this, but surely the full torque will only happen at top speed as at lower speeds the prop just won't apply much torque. Anyway I have just looked at the 260 specs (we only have a Betas JD3 but you have me worried), got an estimate of the 3LW power and it is indeed marginal. I reckon the 3LW is ok at the 260 light commercial rating but would not meet the heavy commercial rating. So I reckon you are right, I would go for the bigger box. I like the way PRM specify torque as power per per 100rpm!!!. ........Dave

wouldn't a 260 be the better box for a 3LW? ..........Dave

Towergate have a very good reputation and I believe their narrowboat section was actually created by a boater However the company has got very big and I read they are now subject to possible takeovers and the usual capitalist money leaching processes so not sure how they will be in the future. Still most familiar named insurance companies are only smaller cogs in the bigger insurance system. .............Dave .

Its all true what they say!, The Brirgand bend is no big deal, at worse you might need to push the front round a bit with your pole (long shaft). If you phone Stanground in advance they might adjust the levels for you to save the reverse, though this is all a bit unofficial. Salters is fine but check the tides (phone the Lock-keeper), it can't always be done (by anyone) at some Neaps. The turn back into Salters is a bit tricky in a long boat. In fact there are a few potential tricky bits on this journey, some locks on the Nene are very close to weirs, there are some tightish bends and some evil bridges with low arches set at an angle to the river. If you are new to boating, and especially 70 foot boats, I would get a years experience before doing this trip, its well worth the wait. And choose a time when there is not too much flow! ...........Dave

Not sure about this. I might be wrong but don't the regs step up at notch at 20m which makes suitable side lights a bit more difficult on a full length boat. I believe ours do comply and they are big jobbies that get in the way a bit when I walk down the gunnel, also mounted at the engine room rather than the front. I do agree about the steaming light. .........Dave

Thats interesting. We spent about a month on the Nene/middle level/Ouse/Cam this year (actually went past you). Should we ask for a refund for just that month??? At 70 foot and a trading licence we are paying CaRT over £80/month even when not on their waters. Days on the Thames, a week in the dry dock, a trip down to Bristol, it all adds up! ............Dave

If I stop my engine (not a BMC) and immediately check the oil its right at the bottom of the dipstick. An hour later its back up to normal. When an engine is running there is a lot of oil splattered all over the insides of the engine which then drains back into the sump. ...........Dave

I am not sure just how philosophical (and funny) you meant this to be, but its worth a greeny., .........Dave

I get this too and its always worse in the cold weather. I am almost certain this is an alternator characteristic and not belt slip. Not a Delco alternator by any chance???? ............Dave