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MG TD TF 1500 - Generator rebuild

It appears the the generator on my '51 TD #5999 is on the fritz and in need of rebuilding. It is only putting out about 1.5 volts.

I called around and found a shop that rebuilds generators/alternators. They said to bring in the generator along with the voltage regulator.

This vehicle has a positive ground system. Does that make a difference in how the generator is rebuilt?

Thank you for your help.
J. McLeod

J, I think that you misread the instructions in the other forum about testing the generator - on that forum, you said you connected your multimeter between the two generator terminals to take the reading. To get a meaningful reading, you must connect the two terminals together with a jumper wire, then connect the multimeter between the two terminals and ground. The reading you are looking for is a rising voltage (with engine RPM) that will go up to 20 volts (don't allow it to go above 20 volts or it can cause damage to the generator. Being positive or negative ground doesn't make any difference when rebuilding the generator. If the shop tells you that the regulator is bad, check with Bob Jeffers at bobj50@comcast.net before you spend a lot of money on rebuilding it or getting a new one. Cheers - Dave
David DuBois

Ah! I did misunderstand. I'll try that when I get home tonight. Thanks
J. McLeod

For J. McLeod:

Just saying hello from a fellow Macleod... As an old Scottish Regimantal toast goes - "Here's tae us, there are damned few like us and they're aw deed"

Cheers mate,

Roderick Macleod - Of the Clan Macleod

1955 TF1500 - HDB46/6798 ("Molly")


Rod Macleod

Watch out America. The Macleods are coming out of the bush..My mother was a Macleod from Stornoway iIsle of Lewis. spoke gaelic fluently
Sandy Sanders
Sandy Sanders

Well I feel much better knowing there are other MacLeod's here about! My wife and I visited Dunvegan Castle on Skye a little over a year ago. We also had the pleasure of having the late Chief John MacLeod stay in our home when he last came to Chicago. So all you other MacLeodd's out there "Hold Fast"

Dave:

As you can tell I'm a hard headed Scotsman so it took two of your posts to get through to me! I put a wire between the two posts as directed and was getting a good 20+ volts, so I guess the suspect must be the voltage regulator. It is a five terminal model and obviously aftermarket since it is marked "Made in Germany". Popping the cover, the internals look all bright and shiney. Could it be something as simple as a bad ampmeter?
J. McLeod

J Macleod. You could try and burnish both sets of points on the regulator,. Sometimes they get a bit crusty and fail to make contact.
Sandy
Sandy Sanders

Be sure to disconnect the battery before burnishing the points in the regulator or you will let the smoke out of the wires.

If you are just not seeing any charge current, the problem could well be the ammeter (although if it were the ammeter, you probably wouldn't see any discharge either). I think now that I would say is the time to contact Bob Jeffers, our resident charging circuit expert. Cheers - Dave
David DuBois

If your regulator is like the one I had, probably is, there are no adjustments in there. In my opinion, it will be best used as a case for the innards Bob Jeffers can put in it.
Tom

I'm lurking, so far good advice. Sounds like one of the voltage coils is open. Seems to be a common mode of failure with the repro's.
Cheers,

Bob
R. K. (Bob) Jeffers

Fer the McScott's


LED DOWNEY

For J. Mcleod:

Glad to hear that you had the honor of hosting Chief John on his visit to your area... I too have been to Dunvegan, and have visited the Isle Of Skye a number of times over the years. Many years ago I had the pleasure of meeting Dame Flora Macleod, who was then Chief of the Clan... I am originaly from Gourock, my father was from Greenock, and my grandfather and several generations beyond him were all from Inverkirkaig (Assynt), Sutherland (Macleod's of Assynt)... My Grandfather, Norman Mcleod was born 18 January, 1862 in the village of Inverkirkaig...

As I said earlier - "Here's tae us, there are damned few like us and they're aw deed"

"Hold Fast" and "Lang may yer lum reek."

Cheers,

Rod Macleod - 1955 TF1500 - HDB46/6798 ("Molly")
Rod Macleod

Bob: Thanks for luking, I'll be sending you a email about your service.

Rod: You and I may be related. I too am a MacLeod of Assynt. My grandfather was born in Lochinver, Assynt, Sutherland in 1821 and imigrated to Canada in 1845. I had the pleasure of fly fishing the kirkaig river when I was over there.
J. McLeod

Make that great grandfather. I'm not THAT old!
J. McLeod

For J. Mcleod:

I thought there must have been an error in the birth year you mentioned, or it was a more "distant" relative... Either that or you are verging on "immortal"... LOL...

Cheers,

Rod Macleod - 1955 TF1500 - HDB46/6798 ("Molly")
Rod Macleod

I'm somewhat at a loss here. The generator checks out at about 20 volts @ ~ 1000 rpm. I installed the new solid state voltage regulator (beautiful job Bob!). Still the needle on the alternator does not move neither charge or discharge. What to check next?
Thank you gentlemen for all your help.
J. McLeod

Check that the charging circuit is routed through the ammeter as it should be. If it is, then check that the needle of the ammeter is free to move and that the vane is inside the loop of heavy wire inside the ammeter. Cheers - Dave
David DuBois

J, the immediate indication of whether, or not, your ammeter is working is to see if it shows a discharge when you turn the lights on with the engine not running. Take your meter and connect it between ground and terminal A on your new regulator (key off). Do you read battery voltage there?
Bud Krueger

Thank you for your replies. With the ignition off, I get 12.4 volts from the "A" terminal on the voltage regulator to the positive terminal of the battery. When I switch on the headlights with the ignition off, the ampmeter shows about a 1 amp discharge. I would have thought there would be more needle movement than that. Maybe the system is charging after all.
J. McLeod

With the lights on i think it should drop a whole lot more then 1 amp? Do you have a spare ammeter (you can get a really cheap one at any local auto parts store).
gblawson (gordon)- TD#27667

Right after you start it, the ammeter should go a ways off the normal mark. Then back to pretty much center as the battery charges back up from the start. If you're driving the car, you should be able to tell pretty easy if it's charging OK. One of those portable gel cell packs is pretty handy until you trust it. Or jumper cables if you trust others. Or a buddy to push ya.

For a daily driver, I like the idea of an alternator (should be easily reversible to the next owner). They just charge better.
Tom

Rod, could please explain to this Englishman what "lum" is?

I am slightly concerned that I may have some or one and would like to take preventative measures in case it may start reeking and embarassing both myself and others nearby.

Thanks.
G.E. Love

For G.E.Love,

The Scots have a few interesting and often benevolent sayings, that are spoken upon meeting or departing from the company of friends (There are others for our enemies that are somewhat universal)...

The saying, "Lang may yer lum reek" is translated as follows: "Long may your chimney smoke." It's just a way of wishing someone comfort and prosperity...

So, you need not be concerned as to embarassing yourself in public - "reek" is easily understood, but as you can see "lum" has nothing to do with the control of bodily functions as you may have thought...

Cheers,

Rod Macleod
Rod Macleod

This thread was discussed between 26/03/2008 and 13/04/2008

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