MtB

Would your dog be ok if the displays were all "organised" then? How would it know?

And?!

Indeed! Like all "Billy big-balls" battery installations, its the charging that's conveniently swerved.

So it won't be running off a Honda EU20...?

Can we have a look at the battery charger please?

Of course it will work fine, probably for long periods. Then one day his battery will get full and the BMS will disconnect the alternator while charging at full chat. Even then he might get away with it. And on another day he might not. A kind of Russian roulette, really.

Otherwise known as a "hose pipe"... Just syphon the excess out!

Is there any other type of fuse?! Aren't all fuses "disposable"? Just curious really...

There is also Electro Start Ltd in Daventry. Not used them myself but I've heard people speak highly of them. https://electrostart.co.uk/ But before shelling out £400 on another starter you may not need, best to describe the fault on here for confirmation it isn't something simple you're overlooking.

My own experience is it's closer to 2% or 3%. But you only need enough to counter the self-discharge effect.

I wonder if you could expand on how you know they "hardly move", please. Unless of course you are moored amongst them and "hardly move" yourself, also. Much obliged.

Don't attach too much importance to my comments. I'm not expert, I'm just posting my opinions based on info in the thread for you to evaluate and see if anything helps. And here's another observation or three. Firstly, you already have a 'cogged belt' as suggested upthread. Secondly, I don't think your pulleys are matched. Your cogged belt nestles deeply into the alternator and crank pulleys, but is sitting proud on the water pump pulley. I think this is the root of your problem - the water pump pulley is for a narrower belt than you are using but a narrower belt would 'bottom out' in the other pulleys so I think your wter pump pulley needs changing to match the others. Finally I'm impressed with the 'new engine' photo. Lots of engine rebuilders spray absolutely everything with paint including the V belts, alternator, rubber hoses and plastic bits like the filler caps.

You're gonna build a butty for the NORWAY after two years?!!! YAY!!!!

Mind you, you forgot to include "Consequences of ignoring the regulations: none". Which pleases the 'inland boating world' you mention, enormously.

I'm not entirely sure there is much to worry about with an out-of-the-water survey on a fibreglass boat. Other than that no major accident damage gets revealed. Steel boats on the other hand....

And how would you know this? Lemme guess... you are on the Kennet and Avon... 🤣🤣🤣

And if the OP's alternator controller doesn't do this and he is possibly drawing that 70-80A at say 1,400rpm, I'm not particularly surprised he is wearing out a belt in 50 hours.

Frankly, "the paperwork" is probably someone's best guess just from looking at it. What paperwork do you have, exactly, that says its a 4108? I think there is bound to be a way to differentiate a 4108 from a 4107, but these are not common engines in a narrowboat so there may not be a great deal of expertise here.

I was just thinking that too. 80A at 13.6 Volts is over a kW of power transfer, and must be right at the upper end of the power a single V belt can deliver. Also, the lower the engine revs when charging at 80A the higher the drive tension in the belt, and more probable slippage of the belt in the alternator pulley becomes.

Not entirely sure we had JPG photo files either back in 1973!