Antares_9

It's not likely that both hubs would spin Ian, that's why I had discounted it up to now, but then I realised I'm not sure what effect just one spinning would have either, it may be that it would allow the other to spin up to revs without any appreciable speed increase. The extra coat of underseal wouldn't make any difference at all.

I reckon if you put counter rotating props on the wrong legs you would loose a lot of speed Ian, boats tend to go a lot slower astern Has something changed that may have caused a bit of turbulence ahead of the props, can't think that would be the case but just another thing to consider. Another posibility of course is hub slip.

Not a theroy Ian, proven fact, and yes it would, the amount of oxygen in the air makes a real difference, on US boats delivered to lakes at higher altitudes, not massively higher, the carburetion is significantly altered by the commissioning dealer to compensate. Obviously the smaller variations in available oxygen per Cubic foot of air due to changes in local temperature and air pressure are impractical to cater for on a carb motor but it is an interesting phenomenon and possibly when coupled to other things could result in a larger cumulative effect. You could always crack open the valve on an NO2 cylinder near the carbs.

You can discount the prop theory Ian, thats why the racers polish them :-D Are the legs trimmed the same, are the tabs (if any) deployed to the same extent and as Rod rightly says, when those two are combined is the ride attitude the same, as reduction of "wetted area" is probably the biggest factor once you get past the low 20s. How old is the fuel, petrol degrades in a relatively short time, though probably not to the extent to cause a large difference, when did you last have the engines state of tune checked, there are so many factors to take into account. One other point of interest, you would certainly notice a reduction in speed last weekend, over a cold crisp day with high pressure due to the high temperature and therefore lower oxygen content in the combustion air, but to what extent is unclear. In any case 30 is fast enough for anybody

Oi Perry, what's wrong with the fenland drains? :-D

Maths lesson for you Jonny, first metre £11.99, further 9 metres to take you up to 10 metres @ £0.40 per .25 metre, so £1.60 per metre or £14.40 per 9 metres, so 11.99 + 14.40 = £26.39 + postage, for your 30 foot requirement 9.25 metres would be the appropriate length by the way so a few pence less than that.

Have you looked on their ebay shop Jonny, they have some of that length for about £20 to £30 each.

Not if you want a good deal Jonny, most people other than specialist control places will not stock the full range anyway, Hindle are in Bradford so just an hour away.

Jonny, measure the length You need from the control head to the other end taking in a nice gentle radius wher it bends, not too tight a bend. Then take the number off the head and ring Hindle, they will fix you up with the right stuff.

Nicely written and interesting account Jonny, sorry to hear about the mechanical problems and it was a pity we missed you.

That looks like a 70's morse single lever throttle / gearchange head Jonny, our friends at Hindle controls hare having a bit of a clear out of longer morse cable at stupid prices (£20 - £30 for a 7 oe 8 metre for instance) there are also some good morse control heads on ebay at sensible money. Hindles shop link below, http://stores.ebay.co.uk/Hindle-Controls_W0QQ_trksidZp1638Q2em118Q2el1247

A wee bit more info if you can Jonny, is the control head a Morse or another make?

Probably better run off 12v DC with one of those stabilised power adaptors from Maplins et al Jill. (assuming it's a laptop and not a power hungry desktop)

Piece of cake, just replace the mechanical senders with the resistive ones supplied with the instruments, they usually come with a couple of adaptors so they will fit most block and thermostat housing thread sizes. :-D You may or may not need to fit a voltage stabiliser into the circuit to prevent false readings, see how it goes, some of the better quality instruments will have them built in.

That's clearer Jonny, you have a matrix fed from the engine coolant, wether there is a webo or Eber in the system is still to be discovered, but at least I now know it can be helped with the addition of a swirl pot in either case. :-D

I think it is you that must be confused Jonny, if you get heating from the engine coolant and a matrix then the Webo is either hot air blown and will not be affected by airlocks in the water system or it is a boiler which heats the coolant like the engine does but when stationary, there can only be one other answer which is you do not have a Webo, only a matrix, I will have a peek at the weekend and will bring the swirl pot in case, also I have a spare 5kw Eberspacher coolant heating unit somewhere.

A question that had occured to me but I was afraid to ask Rod. Jonny if you have a Ebo boiler with matrix for hot water and blown air as you say and it keeps getting air locked, I have a competition "swirl pot" that you can have, if mounted a little higher than everything else in the system it should help purge any air nicely. Let me know and I will bring it to the meet.

Well, I'm not surprised, I've always said if they're good enough for the R.N.L.I .to entrust their boats to then they're more than good enough for me.

Now I think of it, Rod had one fitted recently, sure he will reply, assuming he's onshore.

JPC are agents for Sidepower, also Goodchilds have fitted loads, they have been churning out a German hire boat a month with one fitted for quite some time alongside other fittings so I imagine they'll have had the most recent large scale experience. Cost? depends on the model of thruster and other things like would you want a dedicated battery (recommended), best thing is get a couple of quotes. There are also some new labour saving models now which work on smaller holes and a water pump, but reports so far are not encouraging. Anyway, you shouldn't fit one, you'll upset Jonny :-D

And there's the major point here, NEVER assume (except that somebody a bit thick will take it at face value) anything when giving advice on safety related matters, had you given a recommendation to route the exhaust away instead of just a couple of lines saying it would be OK then POSSIBLY fine, but you have taken two days to actually get round to giving a fuller explanation. My advice would still be just don’t do it unless the installation is checked by a BSS examiner as you have a duty to ensure that all additions made during the validity of the certificate comply with BSS requirements.

Exactly, just the sort of thing you want to be breathing, and that doesn't even allow for basicaly being in a box full of the stuff, which is what would happen if you ran a genny in the aft well.

http://members.lycos.co.uk/bmcmarine/page2.html A good place for origonal workshop manual and also common spare parts Jonny

On a less sarcastic note, I suggest anybody who believes that diesel fumes are not dangerous should read the scientific studies in refferal journals like the Lancet et al, and in particular those by Dr. Andrew Lucking of the University of Edinburgh and colleagues. They conducted a double blind, randomized cross-over study involving 20 healthy male volunteers aged 21 to 44 years. We are talking about close proximity to fumes that can be directed into the boat by the source being close to the stern well. Frankly if I see any more of this kind of advice contary to what is scientificaly proven to be dangerous I will delete it in the interests of safety, nor will I have any truck with anecdotal so called evidence like I have worked around diesels for years and I'm still OK. This is a matter of safety and Co is not the only dangerous constituent of either petrol or diesel fumes, though I accept it is the quickest acting of them.

Yes Jonny, Stranger is right, put a diesel genny in the well and fill the boat with diesel exhaust fumes, they are of course completely safe and healthy