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MG Midget and Sprite Technical - Failed Alternator, Cheap replacement?

Went for a spin ths afternoon and my alternator bearings collapsed and siezed suddenly just short of the driveway after a lovely 40 mile run in glorious sunshine. So I need to change it - I spotted this and wondered if anyone has any experience of these alternators?
Basically I wonder if it's a nasty Asian Knockoff that will self destruct on the day the notional warranty expires?
Price looks too good to be true!

Also, does anyone know if 18ACR is a straight physical replacement for the 16ACR fitted by the factory (other than the higher output rating).

The other thing I noted was that the oil light and charging light are crossed. After I let the engine cool and took off the belt so I could run it up the driveway, I started the engine and the IGN light went out the OIL light stayed on.
I wonder when that happened!

Any insights ratefully received. Cheers.
RS Hughes

I can't comment on the alternator but the crossed oil and ignition warning light was a trick used by unscrupulous car sellers.

If you had a car with oil pressure so low the warning light stayed on, crossing it with the ignition warning light would make it appear the oil pressure was ok, but "the dynamo needs replacing, gov"

Doubt it applies to your car but it could have been done in the past just to sell it and a PO rebuilt the engine anyway but didn't realise the warning lights had been crossed.

Rob aka MG Moneypit

Can't speak for that one, but if you get a reputable make( Lucas, Hella, Bosch etc) from your local motor factors it'll be ok.

The 15/16/17/18 ACR types are interchangeable for all intents and purposes. Even the lh and rh mounting can be changed over easily to suit. An 18ACR is probably a bit over the top unless you have an electric engine fan or other high current extras, but it'll work fine.

Even the later A127 types can be used, the plug is identical.

SR Smith 1

For cheapness go and have a wander around a breaker's yard. going rate is 10. maybe 15 tops. You can often find one that has fairly recently been replaced.
Guy W

Rob, Steve - have you nothing better to do on a Saturday night!!

Rob, that's a very illuminating insight. I hadn't thought of that. As it happens my oil pressure's okay but I do know the engine has been replaced in the past so this may be a legacy of shady dealings in the dim and distant. I never suspected a thing until today as both lights went out as soon as the engine fired.

Steve - your info very valuable, thank you. I have a Kenlowe electric fan fitted by Chic Doig for the PO and I have been wondering about the load it imposes on the car's electrics. I think I will go for a power upgrade in this case.

Thanks again gents. Hope you have a good weekend. I'm going to be glued to the Rugby on TV!

RS Hughes

You're right Guy of course. I didn't spot your post before as I was typing my last.
Sadly my nearest breakers is 140 miles away (I live in the 19th century part of Scotland) but I have feelers out on the 'Net. I think though that I would prefer the comfort factor of a new unit with a decent warranty. That's why I wondered about the unit that appears so cheap, but I've since found OE Lucas alternators at even better prices, or so it appears. I need to make some phone calls to check it out.

Thanks All.
RS Hughes

If it's only the bearings, and you aren't in a hurry, and you like making broken things go again, then put new bearings in it. They're very cheap.
Lawrence Slater


What part of Strathclyde are you in? Still breakers in Irvine.

Also have you tried your local independent motor factors (if you are lucky enough to still have one) if not such people in Glasgow. Then try Eurocarspares who have a few branches in Strathclyde.

On the web there is Minispares, Rimmers plus John Craddock and Dunsfold Land Rover who should sell a suitable alternator at a reasonable price for other Austin, Morris, Triumph, Land Rover models:; (phone them with the Lucas model number of the alternator)

Also Chic Doig sports cars for new alternator, ask if he has a s/h one too.

There are also a few specialist places left that test and rebuilt alternators if you can find them (or DIY route if you fancy it:

Anyone tried ?


M Wood


Repair services (not tried, but in a Strathclyde):

M Wood

Lawrence, I think this one needs more than bearings. I took it off the car yesterday evening, after watching France taking some nasty medicine from Ireland :-)

When I shook it a lot of stuff fell out and not all of it looked like minced bearings. There was some tiny shreds of shiny copper for example, and some smelly burnt stuff which I'd guess was once lacquer.

Makes me think the rotor and stator have been in intimate contact to the detriment of one or both. There's a LOT of movement (radially) at the shaft.

There's every chance this is the original alternator from 1978, so no shame to it. And at least it had the decency to get me within 100 metres of my front door! Even if I did fix it, and I know there's not that much to them, I can't test it properly. Without an oscilloscope I can't really say the rectifier's good for example, or see if the voltage is really stable. A voltmeter's not good enough for that.

Mark, I'm in Campbeltown so a long way from breaker's yards unfortunately. Back when the world was young and the rocks still cooling I used to really enjoy a Saturday afternoon raking around in a scrappie's - it was amazing what you could find and in my case necessary to keep the old junkers I drove in those days plodding on more or less legally. I can remember seeing a 135M Delahaye in one yard in Nottingham with it's chassis broken in two.

In those days you could just rock up with a few tools and wander off into the pile of treasures, later to emerge with the bit you needed and whatever else you could cram in your pockets. It was a great source of spare bulbs, for example! Health and Safety put a stop to that, but it was great fun and I miss it.

I just remembered there used to be a bloke fairly locally who sorted out alternators and starters and had a proper test bench for them. He was a nasty bad tempered old rascal, but he did a good job as I recall. I don't know if he's still at it, but hopefully I'll find out tomorrow.

Thanks All.
RS Hughes

Cheap as chips at paddocks
Onno K


That's useful the Land Rover part number - RTC5084 - as a help search all the other LR suppliers, e.g. John Craddock, Dunsfold, Dingocroft, Frog Island etc (my Series III LR parts book out of reach).

In the good old Lucas days there was a part number crossover parts book so could use all the car manufactures different numbers for the same Lucas component.

Worth noting that some genuine old stock Lucas Land Rover alternators may being sold through ex army surplus. NB want 12V not 24V version.

M Wood


M Wood

You sure wouldn't want a 24V ex army Landie one! The ones I've seen on the FFR Land rovers are huge, the size of a spridget engine.

Worth noting that Lucas as a single entity don't exist anymore, since the demise of the Uk motor industry which was their staple diet.

Lots have paid to use the Lucas logo and the white and green packaging to market parts, but it's not really the old lucas as was. Still lots of NOS about though.
SR Smith 1

bad boy classics do quite a few alternators including bling chrome versions, they seem a good business to deal with, I bought a stalk switch from them a couple of years back but have yet to fit it, I also dealt with them on something else, can't remember what but I do remember they answered my query email to my satisfaction

I fitted a 16/17 ACR 65amp alternator, from MGOC Spares, to my Midget in May 2008 and it's helped cope with my run-on electric cooling fan easily with a battery that is at least seven and a half years old now
Nigel Atkins

I was wondering where in Strathclyde could be 140+ miles from a breakers yard! But I was forgetting that Strathclyde includes the Argyll peninsula. And you cannot get much further down that than Campbeltown! Still, there are excellent Spridgeting roads between there and Arrochar.
Guy W

Thanks for all the info gents.
I lost patience and hit BIN on a new 18ACR on ebay for 39.95 with a years warranty.
I'll open up the dud in a day or two to find out if a repair kit will resurrect it.
RS Hughes

Great roads here Guy, but the potholes are getting very popular hereabouts.
I always liked the A6 down to Kendal. Great for the bike and it was deserted last time I was on it.
RS Hughes

R.S.H. "...nasty Asian knock-off..." you mean like all those unreliable Japanese and Korean cars...?
Nick Nakorn

Not really Nick.
If it's good kit I'm happy to use it. That's why I asked about it.
If it's not good and somebody tells me so, I'll take the advice.
I have a cheap knockoff of a Galaxy Note from China that works brilliantly at a quarter of the price. But I bought a cheap Chinese drill battery once that exploded in my face.
KIP - Knowledge is Power. I didn't have the knowledge so I asked for it and thanks to the guys on here I got some. And I'm grateful.
RS Hughes

Sorted today.
I bought the 18ACR unit from Bad Boy Spares, which turned up today.
The guys at BBS could not have been more helpful. I had called them to check if their free delivery applied to my postcode as it often doesn't. We're a bit remote here.
Yep - no problem, was the answer.
So I asked if the fast courier option at 4.90 was good also and the bloke told me not to bother. They were having issues with the postal service and for the time being were sending everything by courier. He told me to save my money as it wouldn't make any difference.
I fitted the alt and a new belt this evening and took the car for a run.
It's charging at 14.37vDC at fast tickover and 14.31vDC with the Kenlowe fan running. It seems fine, completely silent in operation.
I don't have an oscilloscope so I can't tell much more about the rectification or regulation, but the voltmeter says it's okay.
The only thing I found is that the eye for the adjuster is not tapped like the original, presumably so that it an be readily changed from RH to LH fitting. No problem - the locknut takes care of that.
For what it's worth, if it's any help to anyone, I think it was a bargain and the suppliers were excellent.
RS Hughes

good news thanks for reporting back with this info

I can confirm tardiness, at least, from RM with some of the few items I've sent and received over the last year or so, in fact you've just reminded me that an item I'm now waiting for is about a week late for me receiving it and I'm about only 3 miles from a main 'sorting office'
Nigel Atkins

Doh Nigel! mail isn't delivered from sorting offices, they deal with the input side; it's delivered from delivery offices.
David Smith

thank you for correcting my mistake

it is a delivery depot/big shed that was set up as a temporary stop gap many years ago

my (non)delivery has yet to arrive with me and the supplier as a matter of course has refunded my money despite me asking for the item and not a refund and told me to "please keep the item as a free gift once it arrive there" - so do they think I'm trying it on and/or impatient - if it ever arrives with me I'll resend them the money, that should briefly alter their perceptions of some of their customers

er, no, it's not something from one of the usual suppliers we often mention here
Nigel Atkins

This thread was discussed between 14/02/2015 and 27/02/2015

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