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MG MGA - Alternator heads up and/or question

I converted over to an alternator this summer and have since had a string of small but irritating electrical failures.

First the light switch failed. It appears that there was some internal gap in the hot wire connection and it had been there for sometime. Near as I can tell the increased voltage through the system (old generator was weak)caused large arc that cracked the switch body.

Now the turn signals are no longer working. I'm going to guess that its a similar problem inside the signal relay due to the increased voltage.
T McCarthy

Mr McCarthy,
I'm not sure why you are blaming increased voltage for these failures. The alternator should be providing around 14V, just as your generator should have done, if properly regulating. My alternator seems to be much more consistant than the generator was. Are you sure it's not just the curse of the Prince of Darkness...Mr. Lucas...aka Dim/Flicker/Off? :)
Cheers,
GTF
G T Foster

I think its because the generator was so worn out that it wasn't providing its full generating capacity.
T McCarthy

A properly operating alternator, (13.8-14.2 volts) will not cause the failures you are experiencing. The voltage in an alternator is more constant than the generator. It also can charge better at low rpm. The failures common thread is age not the alternator.
R J Brown

Even if the components did fail due to increased voltage, it's a sign they were ready to be replaced anyay. The electrical system has no trouble handling an alternator. Have you thought about adding headlamp relays to take the load off the switch? I haven't done it for my A yet, but I try not to think about the unfused load passing through that 47 year old switch.

Mark
Mark J Michalak

This thread was discussed between 28/09/2007 and 02/10/2007

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