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MG TD TF 1500 - Electrical conundrum
|I would welcome your advice on the following problem.|
car starts and goes well for 10 - 15 miles then falters and stops.
Fuel fine, but poor or non-existant spark, which recovers after 20 - 30mins. Repeat cycle.
Battery discharges with everything off, and an occasional strange bzzing noise which appears to come from the battery!
Voltage regulator charges upto 30amps at 2,500 revs and does not stabilise lower.
My suspeicion is an overheating coil, but is it a failing coil, or some other cause whihch is overloading the coil.
And whilst stranded was advised (but with limited insight into the problem) with a guy who claimed that his father was George Eyston's co-driver in the Mighty midget, Bert Denley. He was certainly small, like his father.
From your 2 statements, "Battery discharges with everything off, and an occasional strange bzzing noise which appears to come from the battery!
Voltage regulator charges up to 30amps at 2,500 revs and does not stabilise lower."
I'd suspect a bad battery. But I'd also suspect then that it wouldn't crank the engine when it'd quit.
|A W Parker|
|The standard generator or anything close will not charge anywhere near 30A unless something is drastically wrong with the regulator/generator circuit. Standard charge rate max is either 17 or 19A. Such rate as you think you have can only happen if voltage is way high, which in turn means that it is likely cooking the coil and much else, including the battery and generator. It is running at full field and therefore very high voltage, probably 20V+. The battery drain and the buzzing are signs of a dead regulator. If you have to drive it, turn all the lights ON as a power sink (to protect battery etc) before you burn it down, and keep revs as low as possible; this was standard practice back when bad regulators commonly caused overcharging. |
Get a book and do the tests or find somebody who actually knows what they are doing and have it tested.
|Will it crank after it craps out? If so, I would strongly suspect the coil. I had a similar problem with mine.|
This thread was discussed on 19/03/2011
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