How's this for bad workmanship?
 

Here's a picture of the alternator I've just removed. I'd noticed the thing was wobbling and rattling a bit, but when I looked at from underneath I noticed the lug was cracked. And why? Because whoever fitted it didn't have a long enough bolt, so they hacksawed half the lug off to get it on and weakened the casting. As it's been wobbling it's also stripped half the thread. AND it appears they haven't wired it through a charge regulator, so ever since I've had it I've been boiling the battery every day. Consequence: I have a perfectly functioning alternator that's going for scrap, I need a new one at £130 and I'll probably need a new battery very soon too.

I imagine this was the same cowboy who used heat and (I assume) a basic puller to get a brake drum off, relined the shoes and then put the same oval drum back on, then gave it an MOT (probably on the logic that it was an old car that did 50 miles a year so it didn't matter). That cost me money too.

Rant over.

It may be worth asking if someone has a broken alternator. It isn't hard to swap the front housing over. If it is one of the new ones on the market the regulator is internal, the original Volvo ones are external.

Would it be possible to get it aluminium welded then get it rethreaded, i know on my truck we reweld allsorts of things that you think you wouldn't get away with.

Woodman;

I believe that is a failure of the classic quick and dirty alternator conversion where the housing was unceremonially modified (by weakening it, as you can see) so that it is not necessary to install an adapter...one option is to locate an unmolested housing from a junk alt with which to repair that alt. then reinstall with an appropriate bracket (IPD for Bosch SW-EM for Delco)...as far as absence of Regulator, other poster has already touched on the possible answer: internal regulator ...if you post some pictures of the rear contact area, forum should be able to help further identifying the alt.

I also request permission to republish your pic to show what a bad idea the quick and dirty non-bracket mounting method is.

Cheers from Connecticut!

Am I missing something, why is this hole threaded? An alternator isn't "fixed" and should have smooth holes to allow it to be pivoted on the mounting and adjustment bolts.

My alternator has a threaded upper mount (where the belt tensioner is) to allow you just to use a bolt through the tensioner bracket - the thread allows the alternator to tighten against the bracket without using a nut. I suppose it saves using two spanners when you want to remove it, that's the only benefit.

My dynamo suffered in the same way with a cracked lower mount, I don't know why though.

Derek;

You are right of course...I believe that is just remaining evidence, that the pivot bolt was threaded where it went through the housing and vibrated against the inside wall cutting its threads into it...if I look carefully at the threads, the threads look like they are not even in-line with the alt armature...just more evidence of shoddy design and workmanship...the person who did that should maybe stick to video games!

dgbalfour; Cracked housings are inevitably a result of vibration which occurs with sloppy mounting...even with an unmolested housing this can occur...alternators are meant to be pivoted in order to tension belt, the LOCKED in place...at the pivot and tensioning bar...if there is relative movement of any kind, something WILL eventually fatigue and break as a result...

Cheers

Ron - please use my photo as you wish!

Yep, neither the saw cut nor the threaded hole are true to the armature. Bloody hell!

I'm thinking the best use of the old alt is to see if someone wants its innards to recon an equivalent unit. I'll be happier (if poorer) with a new 55amp one with a built-in regulator.

Thanks everyone for your suggestions and for letting me let off steam about crap workmanship!

i have a recon 35 amp external reg' alternator if its any use,
pm me if you are interested

Thanks but I have a shiny new alternator now.