Engine and Transmission Tech

I'm looking for a USA replacement alternator for my factory V8. It no longer has the Delco but a replacement put on in Scotland. I can't ID the one now but it has given up. Did any US or imports to the US cars use an alternator that will fit my car? The tension ear being on top seems to be a problem.
I could try for one from the UK but it would be nice to pick one up from a local parts supply store.

Thanks for any information.
Terry

Have you tried Rockauto - they have a 43 amp alternator listing for a '75 MGB GT 3.5L V8.
[www.rockauto.com]

Thank you, yes I have. Was on the phone with them yesterday. They say the picture is correct for the listing but it is not correct for the V8. That one would appear to be for the 1800 B, the tension ear is in the wrong place. Looking at the V8 alternator from the front the tension lug should be at 2:00, not 10:00 as the standard B or most anything else for that mater.
I have found the TR-7 to look right but would still have to order one to find out for sure. Anyone ever use a TR-7 alternator on the V8?

Terry

In order for some of us to be able to help you better, do you have pictures of the installed alternator?

Can you tell what brand it is (Lucas, Denso, Bosch, ??? since you mention it isn't Delco).

Post a picture, why didn't I think of that? I couldn't even find the button to start a new topic.
Here is what it looks like, the supplier in England was WOSP, it replaced the original Delco the car came with. They still list it on their site but the shipping makes it worth finding something here.
Also what it looks like on the car. It's an 80A, way more than I need anyway as I am am not adding anything to the car in the way of lights.
Terry







Edited 1 time(s). Last edit at 06/21/2015 06:29PM by N7614Y.

You could also take it to a alternator/ auto electric shop to be rebuilt.

That has been talked about, we have a great shop here in Dayton. I would like to have the same type for a back up, they both need to be either the single loop connector or the Lucas style plug for easy change on the road. We drive the snot out of our cars, East coast or West coast, where ever the show is. After Louisville MG2017 is going to be in SoCa. We will be there. I like to carry lots of spares.

I have a similar alternator on my Minor and Minis. It is basically a copy of Bosch (that´s what my auto electric shop told me) and a replacement for Ford Escort / Sierras. My alternators are a bit different because the have also Lucas style connector which I am using. There is also LH and RH side versions of this particular alternator, depending on which engine it was fitted on.

Nice pics. :)

Easiest option would be repair and / or overhaul of what you have (as others mentioned) by that time your overhaul shop should be able to get you a quality duplicate.

Other options include getting a pair of Delco alternators with appropriately clocked mounts.

If you choose Delco, do yourself a favor and connect all 3 wires, it will begin to charge (excite) at a lower engine speed and more accurately regulate system voltage.

Other brands (Motorcraft, Denso, Bosch, Lecce Neville, etc.) are viable as well.

Most of my experience with retrofits (refit in your case) is with Delco, hence my bias.

No Erik, the easiest option is for me not to screw up in the first place! After getting the alternator checked and was working as it should I put it back on the car, same result. After pulling out some hair and a few choice words I was reading on the Delco site. Then it hit me, tech tip, don't use a LED bulb in the warning light. No excitement voltage going to the alt. Or use a resistor across the bulb. Anyway problem solved, thanks to everyone that offered help.
The engine bay is now done, lights all working. On to the carpet and bleed the brakes and clutch. Club Pub Run Sunday, I'm hoping to drive the V8 if no more problems crop up.
I hope Romeo Fox Victor will be on the road soon.
Terry

Terry, Very nice looking engine compartment!

I have to believe that converting back to a Delco alternator will be the lowest-cost and easiest-maintenance solution. The 12SI family alternators only come with mounting lugs 180 deg apart, but the CS130 has a variety of mounting ear options, as shown below:

The Delco is probably the cheapest option. Like engine choices though that does not necessarily make it the best, particularly where space is limited but a great number of conversions have been done with good success. I even had one on my stock MGB.

First determine your amperage needs. There is little point in hanging a 130 amp alternator off the engine if the car never needs more than 20 amps except during cranking. Millions of GM cars did quite well with a stock 27 amp alternator. You can add up the amp drain of all the circuits or simply read an ammeter with everything turned on and the alternator unplugged.

Delcos and nearly all other alternators can be "clocked" to put the mounting lugs in a favorable position, so this is not usually a valid selection criteria.

However, size is. Denso has been the smallest for a few decades but I haven't looked at the most recent offerings and suspect GM may have something new that is worth looking at. A new design wrinkle is an alternator with a stationary rotor coil. No more brushes. I haven't seen a small one yet but hope they are out there. Look at Mercedes, etc.

Brackets are easy to make compared to other considerations. Pasteboard, a good straight edge and string are your friends here. Don't be afraid to try it, a good result is quite gratifying. Try to make it look good. Stainless is a wonderful material to use here, it makes strong but thin brackets possible. Proper gusseting is recommended. Screw type adjusters eliminate the need for a curved slot and make adjustment more positive. Boat and aircraft supply may have helpful pieces.

An external voltage regulator is always an option, widens the choices and makes maintenance easier. Example:
[store.alternatorparts.com]
Search: adjustable alternator voltage regulator
They are adaptable to any alternator configuration including the old externally regulated Delcotron or a custom build:
[forum.britishv8.org]
1/4 way down the page. Externally rectified and regulated with a pancake fan for airflow.

The ultimate is a rotor built into the flywheel and used for both power generation and starting. Rare earth magnets and aluminum flywheels make this a possibility but the stator coil would have to be custom fabricated and hand wound. Currently best suited to hybrid vehicles.

Jim

Do you think that is a Lucas? I have one that came off of my TR7 and it isn't supposed to be very old....