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MG MGA - Regulator Question

Hi,

I've read lots of posts about this. Measurement from D to the ground ( metal bracket of the regulator ) reads infinite ( same as putting the two leads together ). My ignition light glows brighter as I rev up and the battery eventually goes flat. The generator is putting out 16v max.

New regulator ?
DA MacFarlane

I suggest you do the test as described in the workshop manual.
The ignition light should go out once the engine runs above 1000rpm (i.e. when enough voltage is reached to close the relay).

It may only be a matter of adjusting the regulator. It is a bit tricky but works.

There is also a dedicated lucas regulator tests manual on Barney's page that I found the most useful.
http://mgaguru.com/mgtech/books/books_3.htm

tell us what the results of the test are.

My guess is the relay is not closing at the right time in order to charge the battery.
Gonzalo Ramos

As Gonzalo says, "do the test as described in the workshop manual", but if your generator is developing 16v (which is not far off the correct open circuit regulated voltage) it sounds like a faulty (open circuit) cut-out coil. In the end you will probably need a new regulator unit unless the coil fault is obvious, i.e. broken wire or bad connection external to the coil bobbin.
Lindsay Sampford

I suggest you do the test as described in the workshop manual.
The ignition light should go out once the engine runs above 1000rpm (i.e. when enough voltage is reached to close the relay).

It may only be a matter of adjusting the regulator. It is a bit tricky but works.

There is also a dedicated lucas regulator tests manual on Barney's page that I found the most useful.
http://mgaguru.com/mgtech/books/books_3.htm

tell us what the results of the test are.

Gonzalo Ramos

This is my main concern - when I began the tests. From a previous archive's instructions:


Measurement from D to the ground ( metal bracket of the regulator ) reads infinite ( same as putting the two leads together ) - should be 75 ohms according to this post.

The person basically suggested that this was an indication that the regulator was shot. - open coil.

By the way, know any decent MG shops in the Tampa Bay area ?

Thanks,

Duncan
DA MacFarlane

Try Glen Lenhard at:
Glenn's MG Repair
3130 39th Avenue North
St. Petersburg, Florida 33714
Toll free (888) 521-9890
Local (727) 521-9890
Fax (727) 521-9890
Web site: http://www.glennsmg.com

About 20 years ago this used to be Bay Imports with Glen and his partner Kurt Languiraud. Long story, and a lot has happened since then.
Barney Gaylord

This thread was discussed between 19/06/2010 and 21/06/2010

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This thread is from the archive. The Live MG MGA BBS is active now.