MtB

The country is broadly cut in half by narrow-only waterways. South of the narrows you can do the K&A from Reading to Bristol, The Thames from London to Oxford and a fair bit further, and the Grand Union to Braunston then (nearly but not quite) Brum. North of the narrows, who cares!

So can I... Scrap it and get a vehicle with the correct number of wheels - 4 (best) or at a pinch, 2...

Mind you, I can see pressure on insurance companies to distinguish between (safe) LFP and other (incendiary) L-ion battery types developing. Also, its a bit weird that insurance companies don't seem to mind megaWattHours of highly flammable petrol being kept in boat fuel tanks, but get the shivers at a boxful of electricity.

This is a disappointing development. More competition for CRT on-line moorings!

I reckon my 1994 38mm shaft which fitted the 1:12.5 blade was metric! Something in the back of mine says English boats had 1:12 and continental (or USA) boats have 1:10.

Yer welcome. Actually too many variables I suspect. Imagine you spray the monitor with your CO spray and it doesn't go off. What now? More spraying in case you did it wrong first time? Discharge the whole tin and keel over from CO poisoning yourself? Something else?

Here's a result. I just measured the boss on the blade Crowthers made for my old Kelvin K1, which I know fitted the 38mm shaft of my 1994 boat (Beta BD3 originally). Hole at the small end 30.3mm Hole at the large end 37.5mm Boss length 90mm So 7.2mm reduction in diameter over 90mm. Well I never, I make that 12.5:1... !!! ------------ Here's another. The blade that came with my old Lister HRW2 out of a lifeboat: small end hole 30.6mm Large end hole 37.8mm Boss length 91mm 12.5 again!

Sounds a whole lot more difficult than using my lovely old* Moore and Wright vernier!! * Albeit not so old as to be imperial, sadly....

Too many failures, probably!

Got me worried now. I have a variety of props lying about here in the hovel. I'lI have a measure although its harder to measure internally. I had a 38mm prop bored out to fit my new 2" prop shaft by Norris before they folded and I'm 100% certain I asked for a 10:1 taper (which I'd measured on the shaft). It fitted perfectly but now I'm wondering if I'm cracking up!

I don't think so. I used to watch mine do exactly the same when I took them up the knee, years ago when I was the only BMS. I don't see that top balancing these tiny amounts of charge matters a jot. The difference in total battery capacity is negligible and when discharging, removing a jot more of charge at the bottom knee has a far smaller effect on cell voltage as the gradient of the bottom knee is far more gentle.

Quite so. Advice like this is not published by governments not so much as to avoid accidents, as to assign blame. And it will assign blame incorrectly in the case of LFP cells. Or do we now all accept that LFP cells can suffer "thermal runaway events", as the government document states?

I very much doubt the know-alls rely all that heavily on government advice. I certainly don't! Well here's a quote from it that doesn't apply to LFP (as I understand the characteristics of LFP): "2.2 A key hazard of lithium-ion battery installation is that a single cell defect may cascade through a module, and an entire battery system, quickly turning into a thermal runaway event and a full fire incident. "

Are you viewing the pic on a decent sized computer screen? Or a tiny phone screen? It all looks parallel to me, but now the rubber in the Centaflex has torn the engine mounts have relaxed and the offset in centreline alignment is visible.

BR is answering a comment about a different engine, where the author is describing a fault he'd suffered that sounded a bit like the OP's problem initially. Lol, but I get the impression the OP has established for certain the CentaFlex had busted!

In fact looking at the first photo, the prop shaft flange looks noticeably to the left of the centreline of the gearbox output shaft. Or it might be an optical illusion in the photo.

I'd say with the arrangement as far as I can see in the photos, the prop shaft is doing a fair bit of the work of keeping the engine in position, especially if any or all of the engine mounts goes soft or sags. Also if the engine was not carefully lined up accurately in the first place, any stress applied to get that coupling engaged and fitted in the first place will have remained on the coupling for the whole of its life. With an engine on rubber mounts I like to see a pair of UJs to take up engine movement, and a sliding spline with a thrust bearing such as a Python Drive or similar. http://www.pythondrive.com/

I'll set 'em up, you knock 'em in!!

Or is it a Sinclair C5?

Cor blimey, next we'll be considering the difference between a buffalo and a bison!!

But I suspect just fitting a new one will eventually result in another failure, if your engine is mounted on flexible rubber feet. Prices in the link I gave... £400-£600 ish

Looks like a "Centaflex" coupling to me. Nosebleed money though! Several to chose from here: https://www.midlandchandlers.co.uk/search?query=centreflex

True. There are 1:10 tapers and there are 1:12 tapers. I generally see 1:10 tapers on narrowboat shafts. In fact I don't think I've ever seen a 1:12. Or is is 10:1 and 12:1 ?