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MG MGA - Alternator Conversion Question

I just installed a Moss Alternator conversion kit in my car and am having some problems. I hooked it up as per the instructions but the ignition light stays on when the ignition is off, even when the key is removed. The light goes out when the car starts.
The alternator does not appear to be charging.
Any thoughts or suggestions?
I have a query in to the Moss technical guys, but thought I would run it by you folks as well. I am good with the mevchanical side of our cars, but have never been any good at electrical troubleshooting.
Thanks,
Rich
Rich McKIe

See last two paragraphs here: http://www.chicagolandmgclub.com/photos/alternator05
Barney Gaylord

Thanks Barney.
I wondered about that myself.
I will check it out tomorrow
and report back

Cheers,
Rich
Rich McKIe

Rich,
Just did the Moss alternator conversion on my 58 coupe. The electrial instuctions provided seemed to be fine. Hooked the yellow wire to one of the large terminals on the alternator and the yellow/green wire to the small terminal, as per instructions. Other fit-up issues aside, works as advertised.

Cheers,
GTF
G T Foster

Rich,
Just saw your post on my earlier thread. The large terminal wire should connect to the A terminal and the small terminal wire should connect to the D terminal after conversion.
Having all black wires could be a bit confusing!

Cheers,
GTF
G T Foster

Thanks Guys,
GTF, The Moss tech guy (William) got back to me with basicallythe same info.
Things are getting more mysterious

Here is what happens:
Hook up battery ground cable-Light stays out
Turn on ignition switch-Light comes on (good)
Start car-light goes out (good)
Turn off ignition-Light stays on (bad)

I repeated this cycle several times this evening, undoing the battery ground cable each time to get the light to go off. A couple of times the light went off as it should, and during these cycles the ammeter showed charging.

Do you think that this may be due to a bad connection somewhere? Possibly a bad relay?
Tomorrow after work I intend to clean connections in the engine compartment, and tin the ends of the wires going into the control box (I have the type with screw terminals) Any suggestions? would the inside of the regulator be harmed by a spray of contact cleaner? (With the battery disconnected of course!)
Any advice is appreciated!
Thanks,
Rich
Rich McKIe

Rich,
Soon I will begin putting my '58 MGA Coupe back together, so technically I'm not converting I'm starting from scratch with a new system. Should I expect the same problems when I install my altenator?
gerard hutchinson

That's a good question Gerard!

I have heard from people who have had problems and from people who have not had problems.
I take into consideration that mine is a very old car whose elsctrical system has been messed with by many different people so I don't expect anything to be straightforward. With mechanical things changes are usually obvious but with the electrical system the results of previous mods and repairs are often hidden.
I intend to replace the wiring harness on my car as soon as the budget allows and hopefully that will correct some of the problems that my car is suffering from. As for now I intend to do a thourough cleanup on the connections in the engine compartment in the hope that will correct the intermittant ignition problem that I described above.
Like they say in the funny papers..."Your experiences may vary"!

Cheers,
Rich
Rich McKIe

The problem has been solved and the alternator is up and running.
In the end the good folks at Moss Tech referred me to a page on the MGA Guru site (Page AC101) which explained everything in simple terms and had a couple of excellent wiring diagrams that made the job easy.

Thanks to Barney and the Moss Motors tech guys!

Rich
Rich McKIe

Rich,
For the curious amoung us, what did you do to clear up the problem?

Cheers,
GTF
G T Foster

In short; I wired the Alternator up according to the diagram on Barney's page and did away with the regulator. When I discovered that my alternator problems were intermittent I surmised that the cause was the 50 year old (bad) connections at the regulator. Turns out I was right so now the old setscrews have been replaced with soldered wire connections

Rich
Rich McKIe

This thread was discussed between 09/10/2006 and 12/10/2006

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