'powdering' of alternator belts...

[Marvo]

Didn't realise he was stateside. He'd probably be better to join an owners club, they're invariable able to supply spares and expertise and I'm sure there'd be more than one of them in the US.

 

[ruston]

Didn't realise he was stateside. He'd probably be better to join an owners club, they're invariable able to supply spares and expertise and I'm sure there'd be more than one of them in the US.

Yes there are plenty owners clubs over here . That car will be one of the first Mini's , I would like to see a picture of it.

The starter button will be between the seats, be worth a fortune here.

 

[Pants]

Thanks all, belt isn't sitting at bottom of the pulleys, though with all the powder being generated, you'd think it quite possibly so.

Question: when I set this up in 2000 with the now-dead alternator, I retrofitted an LED/resistor in lieu of the basic charge-light, since I don't have a standard speedo with a charge light at all. That LED setup worked fine for 14 years (six of them with my last battery). Is there any reason that would change with this replacement alternator? That is, is there any electrical "need" for the voltage-drop across the typical incandescent charge-light, vs my setup, which has some some forgotten small dropping-resistor to protect the LED, and no "filament?" I've always thought the charge-light is simply a diagnostic/alert item, and in a pinch the small lead can be hot-wired, but perhaps that's not a safe assumption.

I re-tested yesterday in situ, and again, found nothing wrong with basic setup - really no reason to run separate connections to test it. But this time, I ran my ammeter directly to the small terminal to see what kind of current might be flowing there, at about 1500RPM - something less than an amp, as close as I can say. But as soon as my probe made contact, there was a soft, but noticeable hum..as if the diodes had suddenly decided to kick in, even though the normal connection is in place? I swapped over to DC volts and got 14.5V off of the system.

Too soon for cheering. Walking around to the driver's seat, the charge light glowed brightly. I revved it up, and...no change. Went back to the bonnet side, put my leads on, and...back to 12.5V, the basic battery voltage, even at 2500RPM.

I hope I'm not missing something, but as of that, I've concluded it's a dud alternator, even if new.

Another thing on the belt-squeal: it NEVER squeals when I have the alternator plug pulled out, therefore I tend to think the squeal is from electro-mechanical loading, not loose/tight/misaligned pulley. Still, I've readjusted tension, yet again, after taking out extra shims that were first put in to deal with a slight crookedness that seemed to appear after installation and testing. Shimming alone can't deal with it, since once bolted up solid, if you're looking for it, you can detect that the alt axis isn't quite parallel with WP or crank...my only guess there is that the alt case was screwed together such that the pivots are shifted off-axis, though it bothers me that it didn't appear so when I first mounted it...so now I am wondering if the case is actually loose, and has 'wandered' a bit since I installed it.

I'm trying to get the seller to send me a replacement, in any case...how much time can one spend trying to replace an alternator, after all?

 

[Barry White]

Quick question a 1960s mini would have been +ve earth from memory have you changed the battery recently or charged it and fitted it the "wrong way" sounds such a simple mistake but the battery is in the boot away from the engine and the original clamps if still there will be marked in reverse of what they should be. all but a few alternaters on cars are -ve earth (heard +ve exist on old cars but I have never seen one)
If indeed this is the case the rectifier pack will be burned out or shorted on both the old and new unit. causing the load on the pulley you describe.

 

[Pants]

Good observation; you're right about the original +earth setup, but this one is far from original...in fact, it's a fiberglass body that's identical (well, mostly) to the original, so my battery leads (both) run all the way from the boot to the front, where I had to ensure that everything got a negative as well as positive connection where required. But no changes in that setup since 2000, and no starting problems, etc, so I'd say that's the wrong tree.

 

[Marvo]

Quick question a 1960s mini would have been +ve earth from memory have you changed the battery recently or charged it and fitted it the "wrong way" sounds such a simple mistake but the battery is in the boot away from the engine and the original clamps if still there will be marked in reverse of what they should be. all but a few alternaters on cars are -ve earth (heard +ve exist on old cars but I have never seen one)
If indeed this is the case the rectifier pack will be burned out or shorted on both the old and new unit. causing the load on the pulley you describe.

I like the way you're thinking Mykey

Good observation; you're right about the original +earth setup, but this one is far from original...in fact, it's a fiberglass body that's identical (well, mostly) to the original, so my battery leads (both) run all the way from the boot to the front, where I had to ensure that everything got a negative as well as positive connection where required. But no changes in that setup since 2000, and no starting problems, etc, so I'd say that's the wrong tree.

And it's not the other way around where you got a replacement alternator that was specified for the original car with a +ve earth and you've fitted it on a converted car with a -ve earth?

 

[Barry White]

All lucas 16 and 17 ACR are -ve earth and I can confirm the small spade conection has no other funtion other than illuminating a test lamp and the unit will funtion without it conected.
the other 2 large spade connectors are the 12+ volt output and connect directly to the battery via the solenoid (in later years by a fusible link or recently a fuse)
A simple test of the rectified pack is remove the belt and spin the alternater pulley by hand (while it is still connected) it should spin free if the pack has gone you will feel a pulsing resistance

 

[Pants]

I like the way you're thinking Mykey

And it's not the other way around where you got a replacement alternator that was specified for the original car with a +ve earth and you've fitted it on a converted car with a -ve earth?

Actually that would be JUST like my vendor to supply such an item and not know it themselves - but I'm thinking that minis left the realm of "positive-earth" when they made the leap to alternators from dynamos in the late sixties. The online parts catalog doesn't show any options for alternator polarity, anyway.

 

[Barry White]

The leap to negative earth was to do with galvanic corrosion and dynamos output either you just flashed the field terminal to polarise it.so negative earth dynamo cars preceeded alternaters (but this aint solving the problem)

 

[Pants]

All lucas 16 and 17 ACR are -ve earth and I can confirm the small spade conection has no other funtion other than illuminating a test lamp and the unit will funtion without it conected.
the other 2 large spade connectors are the 12+ volt output and connect directly to the battery via the solenoid (in later years by a fusible link or recently a fuse)
A simple test of the rectified pack is remove the belt and spin the alternater pulley by hand (while it is still connected) it should spin free if the pack has gone you will feel a pulsing resistance

Interesting...gonna try the hand-spin test ASAP.

But as to that small-terminal connection: truly, this is not required for the alternator to charge? I thought that kind of alt function was possible - but only in alternators called something like "one-lead" or similar. (I think I once rebuilt an American alternator with a very simple retrofit kit that worked thusly - just one connection plus mechanical ground, and it was good to go.)

--Dave

 

[Barry White]

Cut the fault in half by removing the leads from the alternater (insulate securly) then run the engine and see if the belt squeels or powders)
If all runs smooth its unlikly to be a mechanical/belt problem
Then make up 2 cables run one from the earth on the alternator to the earth cable from the battery. the other from the large spade connector to the +ve side of the battery cable (use 8gauge wire) start engine if all connections are secure you should have 13 to 14 v at the battery if not the unit is goosed.

Ps did you try this i mentioned earlier A simple test of the rectified pack is remove the belt and spin the alternater pulley by hand (while it is still connected) it should spin free if the pack has gone you will feel a pulsing resistance

 

[PEG]

...just try a 2 ish watt lamp,wired from 12v,and connect the other side to the charge indicator terminal,via a female lucar connector.
It should take 10 minutes,and will confirm two facts,regarding your issues.
If you were down the road,i would come and do it tonight! :icon12:

*cannot believe it,i still have my old,paper notes on alternator testing,taken from original Lucas workshop procedure.
It clearly states,"voltage should be present,at charge warning terminal,engine off,igniton on"
This is present due to above^ wiring. I have an old Coventry Climax stacker,which has an acr alternator,and stops charging,when the charge lamp fails.

 

[ruston]

...just try a 2 ish watt lamp,wired from 12v,and connect the other side to the charge indicator terminal,via a female lucar connector.
It should take 10 minutes,and will confirm two facts,regarding your issues.
If you were down the road,i would come and do it tonight! :icon12:

If he pays the fare I will come with you and hold your bag.:smile5:

 

[PEG]

My "bag" is happily suspended,where it is both secure and convenient :icon12: but thanks for the thought...

 

[Pants]

Cut the fault in half by removing the leads from the alternater (insulate securly) then run the engine and see if the belt squeels or powders)
If all runs smooth its unlikly to be a mechanical/belt problem
Then make up 2 cables run one from the earth on the alternator to the earth cable from the battery. the other from the large spade connector to the +ve side of the battery cable (use 8gauge wire) start engine if all connections are secure you should have 13 to 14 v at the battery if not the unit is goosed.

Ps did you try this i mentioned earlier A simple test of the rectified pack is remove the belt and spin the alternater pulley by hand (while it is still connected) it should spin free if the pack has gone you will feel a pulsing resistance

Mykey - thanks for all the pointers. I just tried the hand-spin test - no resistance felt (key on & connector in place, right?)

The other test (bypassing existing leads) seems unnecessary to me, though I'd do it anyway if I had a quick-disconnect female terminal of that large (1/2" or so width) size needed - without that, all I have is tiny jumpers that can't handle much current. Anyway, DVM tells me that the stock connections are getting full battery voltage, and have been all along. Same testing tells me alt earth is excellent as well, so I don't now see the point in creating substitute test connections, although it's nice to know it's as simple as making up one hot-lead.

No, the squeal never occurs when the connector is disconnected. I was tempted to conclude that this points to an electrical problem, but I suppose it doesn't entirely rule out belt issues (though I have no concern about that really being the problem at this point.)

I'd rebuild my two old alternators (both of them higher output than the new one, which at this point I really want to condemn 'cause...well, it's got ZERO output) but it looks like the separate rectifier/brush and diode assemblies would cost 3/4 of what each complete alternator would.

Specialty shop tested my old one, and told me yesterday that diodes are shot, and that this is typical of overworked alt trying to charge a bad battery. How crazy would it be to test/replace diodes right on the board? Seems to me diodes are cheap, and I've no problem soldering...