So I've just spotted that my fan belt is a crumbling mess. Probably and obvious question but even with a new battery recently I haven't had great battery life, is it possible/likely that the cruddy fan belt has led to sloppy charging from the alternator?

I'm hopping so as there's nothing in the way of accessories leeching power, but I have found some electrical tape bodgery recently it'd be nice if it was something as simple as a dead belt!

Cheers

Nick

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Basil - 1978 Leyland Mini, Brooklands Green, bit of a bitsa, and a park brick in the boot.

Yeah bad fan belts will slip on the alternator well before they even get to crumbly. Then poor charging.
Get a new one, they are cheap. I use the QH ones from Karcraft, but Bosch are OK too.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Cheers Doc, I'd already added it to my list for the next Karcraft visit. Fingers crossed that there are no other hidden bodges affecting the battery life.

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Basil - 1978 Leyland Mini, Brooklands Green, bit of a bitsa, and a park brick in the boot.

Check the alternator pulley too, the sheet metal ones eventually wear to a `U' shape. Then even a new belt won't grip properly.
I replaced mine a while back with a cast iron one I got from the local auto leccy.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

replace the belt (if it crumbling it is well overdue for replacement) then check the charge rate of the alternator, it should be around 13.8, u can check it at the battery or the alternator, if its fine at the battery then it should be ok but if its low at the battery check it from the alternator as it could be a dodgy cable. For those who dont know how to check voltage put a multimeter across the terminals to check voltage, and for the alternator put the + probe on the output cable and the - probe on an earth

Measured V with engine doing 2000rpm or more should be 13.8-14.3V. Lower than 13.8 you have a problem- mine was a bad crimp on the thick brown wire at the alternator.
Crimped + soldered a new one on, now all good.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Well I put a new belt in last week(along with hoses, thermostat and housing) but only took it for a decent drive last night. The whirr of the alternator fan was a bit surprising at first!

Thanks for the help/pointers, its really appreciated when you're trying to get the hang of owning a mini

Cheers

Nick

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Basil - 1978 Leyland Mini, Brooklands Green, bit of a bitsa, and a park brick in the boot.

That noise isn't the alternator fan, it is just the alternator turning mechanical energy into electrons- 3 ph AC, then 14V+ DC.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

That makes sense!

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Basil - 1978 Leyland Mini, Brooklands Green, bit of a bitsa, and a park brick in the boot.

Make sure You do not put to much tension on fan belt
It make cause some noise from the Alt bearings

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" A Hundred Years From Now It will not Matter what my Bank Acount Was,
The Sort Of House I Lived in, Or The Kind Of Car I drove ... But The World May Be A Better Place
Because I was Once Important In The Life Of A Child"

Mein Gott, who has a Mini so quiet you can hear the alternator turning???

Cheers, Ian

You Will hear it if the bearings are stuffed

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" A Hundred Years From Now It will not Matter what my Bank Acount Was,
The Sort Of House I Lived in, Or The Kind Of Car I drove ... But The World May Be A Better Place
Because I was Once Important In The Life Of A Child"