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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Bosch alternators

I've noticed a fellow on eBay who is selling what appears to be the Bosch alternator that are a bolt-in replacement for the Lucas 16ACR alternator. This is the third one I've seen up for bid:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33573&item=2429577631

The first one went for USD $88, the second for $103, but at some point soon, the price should drop. I emailed him early on, and he claims to have a huge stock of them, so don't get carried away in bidding. Get the price of one at your local parts store for a reality check.

I have no interest in them, since I just finished converting my '67 GT to a 73 amp Delco 12SI (goes real will with my GM HEI distributor).

Regards,
Jerry
Jerry Causey

Hey Jerry-

Details on the HEI? I understand somone up in Oregon was building them, but when I tried to contact the number I was given I got some kid.

Thanks

greg
Greg Fast

Thanks, Jerry for the heads up on the Bosch Alternators, as you know, there are still people out there who are looking for a source.

I am waiting to see what develops for a much more recent alternator substitution, as from current production vehicles. The Bosch's, Si's, and rebuilt Lucas's are all getting long in the tooth, and there are smaller, lighter, but equally capable alternators out there which are only just starting their production lives and parts availability.
Bob Muenchausen

I picked one up from a local salvage yard, [breaker's to you Brits] for $9, yes Nine dollars. They were glad to find a sale.
And it did take a small modification to the terminals to make it work. Otherwise, a bolt on. On my voltmeter, it is only producing 13.5 volts which is worrisome. but only time will tell.
I am still interested in the Hitachi replacement though, it's smaller/lighter. My theory is, if you can't make enough power to keep up to modern traffic, then start throwing weight off.
[maybe I should think about some weight loss myself?]
Safety Fast
Dwight
Dwight McCullough

Bob,
I checked out more modern Delco units before I converted mine. They are much smaller and lighter, but put out waaaay more amps (over 100) than I would trust through the B's wiring harness. As it was, I doubled up on the power wire to the starter connection with just(!) 73 amps available. The newer units also have a serpentine drive belt pulley, though that can be replaced with a v-belt pulley. I think rebuilt 10SI and 12SI alternators will still be available long after I'm gone from this earth, and I've saved a couple of Lucas alternators, brackets, and connectors for the next owner of my B to worry with.

~Jerry
Jerry Causey

One thing to keep in mind when choosing an alternator replacement is the availability of a replacement if it should ever fail while you're out of town. I was traveling with a friend who had a Chevy 350/TR6, using a small alternator he had put together out of two or three different alternators (mostly Honda) to get it just the size and mounting he wanted. We spent a day and a half at an alternator shop while the owner put together a replacement, using parts from his spares bin and parts that had to be ordered and shipped in express. The bill was $150, which was very fair, considering the effort expended by the owner and the cost of the replacment parts.

This car now has a GM/Delco unit, which can be bought in just about any town in the USA, off the shelf. It's not as nice as the one he had, but....! A replacement for the GM runs around $30-$40.

As for swapping a V-belt for the serpentine, be careful. The alternator doesn't care which way it spins as far as producing electricity is concerned, but the cooling fan does. If you are pushing the alternator near its capacity, you may shorten its life due to overheating if the fan is running the wrong way. And maybe not, just something to be aware of.

Most of the older alternators had external cooling fans, which could be swapped, but many of the newer ones have the fan internal to the alternator.
Dan Masters

Doesn't matter how much an alternator is *capable* of putting out, it will only actually put out as much as the cars electrics demand.
Paul Hunt

All of the considerations mentioned are reasons why I suspect we labor on with the vintage stuff still available. They are simple, they are engineered from the same paradigms of the period they are from, and the systems they interact with are designed with these things in mind.

I am probably wrong to be concerned about the age of these alternators when they are so available now. And perhaps, given the cyclical nature of people's interest in these cars, it really doesn't matter any more than whether parts used on Model A's are not modern. Like Model A's and Model T's, such considerations may be a moot point in time anyway.
Bob Muenchausen

I recently added a Delco to my '77B and it was a snap to install. It actually goes in upside down and making the connections were very simple. Electrics seem to be much better, brighter lights, better pickup and with everything working ,including fog lights and twin boosters for the carb, the ignition light barely flickers.
victor gardino

This thread was discussed between 03/09/2003 and 08/09/2003

MG MGB Technical index

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