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MG MGB Technical - GT didn't start

ok here is the problem: battery flat 3 days ago due to a leaking terminal so after cleaning and charging car was running fine until yesterday I tried to start it and .... battery full, ignition lit on, and this quite loud noise under the bonnet like a tapping noise when I tried to start it so my conclusion would be ... starter or solenoid ?! am I right? I'll have a look this evening but any ideas would be useful ?

thank you
Alexia
Alexia

This is a GT 72 !!
Alexia

Yes you would be right if the battery was OK but I don't think it is. What is this leaking terminal ? Are the terminals tight and clean. Clean them by pouring a little boiling water over them, smear with Vaseline and tighten them. If a battery post is cracked you have your answer.
Iain MacKintosh

"Ticking noise"

Sounds like a dead battery to me.
Luigi

but I cleaned well with boiled water and recharged the battery, well I think so and when i turned the key there is power so if one of the batteries was dead then I wouldn't get this would I?
leaking terminal means for me a terminal where I had salts from the solution around the terminal
thanks
Alexia

It seems too much of a coincidence that you had this battery problem in the last few days. It sounds like there's not enough power to turn the engine, but enough for the starter to try. Have a go at jump-starting the car and then look at one of the batteries with great suspicion.
Steve Postins

Alexia

The tapping/clicking noise is a classic sympton of a weak battey, or one with a high resistance connection, even though it may appear to be charged when supppling light loads. When the key is turned to the start position, the solenoid closes and connects the battery to the starter; this draws a high current causing the voltage to collapse with a weak battery; the solenoid then opens, the starter is no longer connected, the voltage rises, solenoid closes, voltage collapses etc - hence tap, tap, tap, tap as the starter solenoid closes and opens in rapid succesion. A battery test would confirm it's condition - if good, reexamine connections.

Good luck

Barry
73B
B.J. Quartermaine

Quick battery test: Turn on the headlights and try out the horn. If the battery is going, it will sound weak. If it sounds good and loud, check your earth strap between the engine and chassis ground; it will show the same symptoms as a weak battery.

Pete
Pete

thanks!! I'll check my battery then.
Alexia

I did the battery test with the horn and the headlights on and it wasnt weak then I tried again to start the engine it nearly started doing this noise again and then nothing except the tappin ticking noise so I guess I have to find another battery...
thanks for you help
Alexia
Alexia

Alex:

You miss-read my point: If the horn is still strong with the lights on, that means the battery is probably OK. Try running a ground wire from the engine block to the chassis ( the jumper cable is the best way to do this) and try again.

Pete
Pete

Pete,

and what should I do after that? should it start? or not?
means my earth terminal/strap is dead?
thanks
Alexia

Alexia:

If your ground strap from the engine to the frame is corroded, the electrons will not have a path back to ground. Remember that your engine and transmision are mounted on rubber issolators. So if you have the lights on, and the horn is still loud, that suggest that there is a big bunch of electrons stored inside the battery: these two items draw a lot of power.I would expect that a battery with enough power to light up the lights (they are bright no?) and sound a clear horn, will have enough power to engage the solenoid, if not actually spin the engine fast.

So, clip one end of a jumper cable to the engine block and the other to the frame where there isd a bit of bare metal showing. Try and start the engine and see what it does.

If it does not start, the solenoid may be bad. There is a way to bypass it by jumping the terminals with a screwdriver.

Pete
Pete

"the solenoid may be bad. There is a way to bypass it by jumping the terminals with a screwdriver."

Just make sure the car is not in gear when you do this as you will either be underneath the car or in the engine compartment and I assume you don't want to be crushed. Oh, and the ignition key should be in the ON position when you do this "bridge"

I still think your battery is not taking the charge or your terminals/starter connection is loose or faulty.

Luigi
Luigi

Alexia. As Pete notes, if the head lights are turned on and the horn will sound strongly, your battery and connections should be good. I have, twice, had the pre-engaged starter, which you have, lock up when trying to start. This will also give you the indications you describe. Try putting the car in 4th gear and rocking the car back and forth. If the starter is jambed, this should clear it. Put the transmission in neutral and try to start it. If it starts, you have a starter which may be going bad. If it does not start, you need to begin to check the problem out in a systematic manner.

First, do a volt meter check on the battery terminals. You should have 12.0 to 12.5 volts showing on the meter. Then, run a jumper wire from the battery terminals to your volt meter (or recruit an assistant) and read the voltage while trying to crank over the engine. You should see at least 11 volts at the battery terminals. If not, bad battery (batteries). If you have good voltage at the battery, but the starter does not operate, take the positive connection and attach it to the large terminal on the starter. Try to crank the car over while taking a voltage reading. Less than 11 volts at the starter terminal indicates bad battery clamps or bad cables. If you have 11 volts or more, the clamps and cables are good. This indicates either a starter problem or, if your year has one, a starter relay problem.

If you have a starter relay, by pass it and see if the starter will turn over. If you do not have one, you will need to change out the starter.

If you can recruit an assistant, have them check for fan movement when you rock the car, in gear, to make sure the starter is not jambed. A seized engine will also give the indications you describe, so make sure the fan will turn as the car moves.

Les
Les Bengtson

Les, I think about a point now I changed the clamps few days ago for new ones on only one battery (the one which was leaking and that I recharged)could it be this? but I threw away the old ones .... another point is that the car after recharging the battery and with the new clamps did work perfectly during one day and then 2 days after i couldn't start it ...
I will try the 4th gear trick though
thanks
Alexia

This thread was discussed between 01/08/2005 and 04/08/2005

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