dmr

From the photos it looks like very localised damage rather than paint failure to me. Take the rust spots right back to bare steel and use a good primer, no need for Vactan if you get to bare steel. Several coats of undercoat to build the level flush with the existing paint, and carefully sand to level. If you then want to paint the whole roof then gently sand the whole lot (except any non slip bits) and put one or two coats of paint on. ...............Dave

Power is simply torque x speed so is a measure of both torque (the useful stuff) and how high the manufacturer dares to set the maximum revs. There are many little motorbike engines that will easily produce 50Hp but they do this only by having a very high rated speed, they would be useless in a boat. ..............Dave

Getting your own engine rebuilt is an option, especially if its a good engine that you like, but proper rebuilds are costly so get a good estimate and see how that compares with a brand new engine. You are correct that if the Beta is 22@2000 and this is the same as your engine then you should be ok with the same prop, you will not be able to use the higher revs but thats probably not a big issue, lots of boats never get to full revs. A good thing to compare is the engine capacity, if both engines make 22@2000 then I would expect very similar cc';s. Best not replace your current eng

It sounds like one of your proposed replacement engines is actually a smaller engine than can rev higher, and so maybe you are getting bad advice from the people trying to sell you a new engine, which is what others have alluded too. As to a bigger engine and skin tanks, don't worry about it. Many many canal boats have undersized skin tanks and overheat if driven hard. So, it takes about 3Hp to push your boat along the canal and so the amount of waste heat produced (to the skin tank) will be similar regardless of if this is coming from a small or bigger engine. With a big engi

Scotland is making every effort to remove navigation from its canals so it does not really matter 😀 ................Dave

My feeling is that something is wrong here. If you have rust then putting lots of topcoat on top might be just a waste of time and money. Are you sure that it really is two pack/epoxy ? ...............Dave

The Nene and over to Cambridge was probably the best trip we have done. We were very lucky as we spent two weeks in Cambridge as we had "help" from a local moorer. It would be a little sad to get to Cambridge and not be able to find a spot...which is quite likely. The rest of it is all very good and interesting too. The Salters Lode tidal bit was tricky in a full length boat. ............Dave

And I reckon Newbury is maybe even more demanding than the Oracle, not as bendy but the last bit going under the bridge is quite restricted. ...............Dave

Alcohol, glycol, sounds close enough to me, but I don't like the colour, it looks like one of those new fangled things that teenagers drink. I've drunk a couple of green beers but draw the line at red and blue. .................Dave

The old one also stores water so does not need a calorifier, but I find the antifreeze does not taste too good. . .................Dave

Gas is much more than £22 just about everywhere because Calor run a protection racket 😀. I am only aware of two cheap places, the "gate in the fence" in Stoke on Trent and a dodgy garage in **************** who does cheap DIY refills. .................Dave

I suspect the op is correct but its a bit academic, spare parts for the lovely old upright models are in limited supply as Alde have declared them obsolete. The new model is somehow less desirable, despite its claimed better fuel consumption, maybe because its fussy about copper calorifiers. ............Dave

Have you not noticed the huge dents in the fronts of those old working boats ? 😀 ................Dave

The very low efficiencies for a diesel engine are based on the fraction of the available potential energy of the fuel that is converted into mechanical output. Lots gets wasted as exhaust and coolant heat. You could do something similar for electric by including power station losses, grid losses, charging losses etc etc. ..............Dave

Calling 1500v DC a low voltage suggests you worked in a very different world to many of us 😀 Electronic engineers regard 3.3 as low, 5 as medium, and 12 as getting dangerous. .............Dave