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T-Series My baby has lost juice - MG TD wont start

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RTMG

RTMG

Freshman Member
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Hi All,

This is indeed a fantastic forum and I appreciate all the help I have been getting. I now have a new problem - my 2nd MG TF Tragedy in less than a week of owning it. /bcforum/images/%%GRAEMLIN_URL%%/nopity.gif

The 1st one was leaky floats - which has now been resolved by replacing the floats. Since then the car started and drove fine... until yesterday evening. Tried to start it and the engine turned a few times and then the battery gave up. Here are the facts and the actions I took based on my very limited abilities:

1. Turned lights on to see if battery had any power - lights and horn worked fine.

2. Jump started car - no problem it started fine.

3. Drove car for a couple of miles and then turned engine off. Started it 5 minutes later - car started fine.

4. Drove car again for a couple of miles and then turned the engine off. Tried to start engine - wouldn't turn again. Plugged in external charger (that a neighbor had) and engine started without a problem. Charger was set to just 6 amps. Hmmmmmmmmmmm. /bcforum/images/%%GRAEMLIN_URL%%/confused.gif

5. I then put a meter on the battery, while the car was running with lights and heater motor (this is a Mark II) turned on, basically attempting a full load. The meter read 11 volts. The Ammeter was showing negative at this point.

The puzzling thing is that the car always started with the 6 Amp charger clipped on the battery terminals the two times I tried it. I didn't really give it any time for the battery to charge as such.

So, I aksed myself if I did anything <u>different</u> the night before, and here is what I can think of:

1. I used the battery cut-off switch that was installed by the previous owner for the 1st time. I can't imagine this causing any harm?

2. I figured out how to turn the panel lights on the night before and was playing with that switch - because it intermittently turned the light on/off - seems to be a bit rough. Don't know if this switch (which seems to act as a dimmer) had anything to do with this problem. Turning off the light switch turns of the panel lights also. Again, I can't imagine this causing any harm? Specially since I used the battery cut-off switch.

So this is where I am now. Sorry for the long post, but I thought the details may provide some insight.

I am now trying to figure out if the problem is with the generator, the battery, the voltage reulator or some other component.

Your advise is appreciated!

/bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif

RT
 
I would have the battery tested. Sounds like it's going bad. Also check that cut-off switch with a meter. Check for resistance (there shouldn't be any) and for an intermittent connection.
 
I think I would check the battery first, is it any good?

Secondly would check the terminals from the battery to the starting circut.

However I would bet that battery is history.
 
The battery looks newer - doesn't mean its good ofcourse. There could be a short in it due to a bad plate or something. I am investing in a Vector VEC1097A tester tonight.

I hope it is something as simple as the battery.

THANK YOU!
 
Any elec shop and maybe even auto zone or such can check battery.
 
Check the battery disconnect for any corrosion, etc. Sounds like a battery to me as well.
 
The battery disconnect is the one that attaches to the negative post on the battery and is essentially a screw knob. Moss Motors sells this type for $13.95 and it looks pretty new to me. I will test the battery tonight.

Thank you!
 
RT - Check the battery voltage with the ignition off and no loads on the battery at all. The battery should read 13 volts or better after having been driven and just shut off. After sitting over night it should read 12.6 to 12.8 volts. The 11 volt reading with the engine running and the lights and heater fan (heater is aftermarket, no TD, MK II or otherwise came with a heater) indicates a sick battery or no output from the generator or regulator. To check the generator, disconnect the wires from the two terminals on it and jump the two terminals together. Connect the negative lead of an analog meter (I am assuming that the car is still positive ground, if not, then connect the positive lead to the jumpered terminals) and the other lad to ground. Start the engine, but don't rev it. Slowly increase the engine rpm while watching the meter. You should see the meter increase with revs to 20 volts - don't let it go any higher as it will increase very rapidly after this point and can destroy the generator. If you are not getting 20 volts out of the generator (even if it reaches 12 volts, but won't go higher) the generator will need to be rebuit. If the generator tests good, reconnect the normal wires to it and procede on to the regulator. For the regulator I am going to refer you to Bob Jeffers at: bobj20@comcast.net Bob is th eexpert on regulators and can provide you with a solid state replacement in the original case if your regulator is bad. Note: all the mesurements have to be made with an analog meter, since the generator produces a pulsed output, a digital will read all over the place rather than giving a smooth incease of voltage as the engine is reved up.

Contact me at ddubois@sinclair.net if the generator is bad and I can guide you through rebuilding it.
Cheers,
 
Aloha RT,

Since you used the battery cut-off for the first time, perhaps you should check that out. I would suggest you reomove it and reconnect the battery to see how the starter reacts. This is a simple no cost test that may solve the problem.
 
You're probably gonna continue to find little things like this that are just a result of non-use...you might want to schedule a weekend to do some serious maintenance/cleaning/general upkeep.
 
Thanks everyone. I have begun the testing process. I really dont think its the battery, because I used a charger/tester/monitor from Vector that shows no error codes and charged the battery. The car starts fine now and there are no issues with the battery now... until the battery runs down again. It may be the generator or regulator. I will try David's suggestions next to test the output of the generator. It could be a cabling issue also - who knows. I will definitely let you all know.

I do have a new issue /bcforum/images/%%GRAEMLIN_URL%%/mad.gif There is what looks like grease spray on the inside of the cowling/bonnet and a bit on the wings. It doesn't look like motor oil - its thicker and its in line with the fan and just in fron of the water pump. There seems to be an opening on the radiator fan shaft that has grease in it. Is that supposed to be open? The spray is on both sides of the fan. Its in a line and it seems like it is a result of something spinning and spraying. Kinda hard to describe. Any thoughts on that?

Sorry to post so many problems!

Thanks for your support.

RT
 
There should be a grease fitting there. Replace it and you're good to go. Be sure to clean out any crud that got in there, and give a little bit of fresh grease to the pump afterward.
 
yep, agree. that cut out kinda bothers me as well.
 
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