Hi to everyone who may read this - and your thoughts and expertise would be most welcome :roll:
The battery on my 2000TC has started to "boil" - after only a short run of less than 10 miles when returning to her there is a gentle hissing noise that sounds just like the rad cap leaking, but it isn't. It is from the battery venting, and it has also ejected some acid from the breather as well. However it does not feel overly warm, no more than I would expect from being in the engine compartment, upon removing the cell caps all the cells are slowly emitting bubbles at the end of such a run.
To my mind this precludes a faulty cell?
I really have to explain the recent "history" of the electrical system to aid a diagnosis.
I have had the car about 18 months now. 4 or 5 months after purchase (everything functioning normally) and 2000 miles into a continental rally the battery was discharging throughout a days mileage of about 400 miles - dead as a dodo at the end of the day, but ignition warning light was not glowing. A fellow rally competitor attempted to show me how the voltage regulator may be at fault, and by the time he had manually opened and closed points and shorted various things in it with a screwdriver (with many sparks and flashes) it certainly was - totally fried and now even the ignition circuit was no longer powered, warning light on constantly and running distance to flat battery with motor actually dying through lack of power about half a day.
A new voltage regulator was sourced (not a genuine Lucas one and looks the same as those currently offered on ebay) and normality was restored.
Back home, car was used for many months until about February when she suddenly (wet night, headlamps and wipers of course) stopped charging sufficiently to reduce wiper speed and battery dead enough not to turn engine over after stopping.
Reason this time was a very slack fan belt - as a result of the bolts holding the dynamo carrier in to the engine block having fallen out!! Bolts replaced, fan belt tension restored, battery recharged (by charger) she was useable again with no charging problems. But vibration of the dynamo indicated why the mounting bolts had fallen out, so removed it again and decided the play in the front bearing was causing the problem. Had a problem sourcing the correct "long" dynamo but fitted a reconditioned "short" (C42 I think if memory serves me right) as per mini and MGB as a temporary measure.
Here I will hold my hands up to a possible relevant error. I fitted the dynamo - nicely marked NEG earth (my 1970 2000TC IS negative earth) started car up everything fine. Only when throwing the box away later did I find the "IMPORTANT NOTICE" at the bottom instructing dynamo must be polarised on fitting. I had not done this, assuming it to be negative earth, but I suppose some marked negative earth will have been repolarised at sometime in their lives? Anyway charging was fine so I didn't worry and assumed everything to be okay.
About three weeks later my daughter (who uses the car almost daily) noticed the ignition warning light on RED continuously, although up until then it had been fine. I found the lead to the SMALL terminal on the dynamo loose, the wire with bare (no solder!) end was swinging loose, the plastic insulation was so brittle it broke in my hands leaving a bare spade on the terminal with no wire attached. New, spade, insulation (and solder!) resolved the problem,normality resumed. Shorlty afterwards my daughter mentioned she had heard a hissing sound under the bonnet when she parked up, which I wasn't unduly worried about as I had just fitted a nice shiny new stainless steel rad cap and thought that would be the culprit.
Now I know it is not the case, but the battery hissing as I presume it is being overcharged :?:
I have attempted to check the voltage regulator and have ascertained that the cut-out (front coil) is functioning - although after reading I now understand this is more of a cut-in and that when the points are closed the battery is then charging. A voltmeter across the battery terminal records 12v with engine dead, rises to about 14v as engine is revved.
The only other thing worth mentioning is I now notice the ignition warning light glows faint red on tickover about 800rpm, extinguishes as revs are slowly increased to about 1200rpm at which point it then momentarily comes back on full very bright red for a couple of seconds before extinguishing again and remaning off. I have not previously noticed this bright pulse as the light actually increases before extinguishing, and again do not know the relevance.
In order to check the charge of the dynamo instructions are to remove the two "B" wires from the voltage regulator, then connect the ignition to the battery in order to start up before taking measurements. I presume this means a wire from +ive battery terminal to +ive coil terminal? I don't want to attempt this without clarification as I afraid to damage anything!!
Apologies for such a long screed but I thought better to explain anything that may have significance to the problem.
Incidentally I have tonight (albeit a bit late) polarised the dynamo as per fitting instructions in the hope :!: it makes a difference - though I doubt it. I am using the car daily myself now to check out the problem.
If you made it to the end, many thanks and all observations welcomed !!
Robin
The battery on my 2000TC has started to "boil" - after only a short run of less than 10 miles when returning to her there is a gentle hissing noise that sounds just like the rad cap leaking, but it isn't. It is from the battery venting, and it has also ejected some acid from the breather as well. However it does not feel overly warm, no more than I would expect from being in the engine compartment, upon removing the cell caps all the cells are slowly emitting bubbles at the end of such a run.
To my mind this precludes a faulty cell?
I really have to explain the recent "history" of the electrical system to aid a diagnosis.
I have had the car about 18 months now. 4 or 5 months after purchase (everything functioning normally) and 2000 miles into a continental rally the battery was discharging throughout a days mileage of about 400 miles - dead as a dodo at the end of the day, but ignition warning light was not glowing. A fellow rally competitor attempted to show me how the voltage regulator may be at fault, and by the time he had manually opened and closed points and shorted various things in it with a screwdriver (with many sparks and flashes) it certainly was - totally fried and now even the ignition circuit was no longer powered, warning light on constantly and running distance to flat battery with motor actually dying through lack of power about half a day.
A new voltage regulator was sourced (not a genuine Lucas one and looks the same as those currently offered on ebay) and normality was restored.
Back home, car was used for many months until about February when she suddenly (wet night, headlamps and wipers of course) stopped charging sufficiently to reduce wiper speed and battery dead enough not to turn engine over after stopping.
Reason this time was a very slack fan belt - as a result of the bolts holding the dynamo carrier in to the engine block having fallen out!! Bolts replaced, fan belt tension restored, battery recharged (by charger) she was useable again with no charging problems. But vibration of the dynamo indicated why the mounting bolts had fallen out, so removed it again and decided the play in the front bearing was causing the problem. Had a problem sourcing the correct "long" dynamo but fitted a reconditioned "short" (C42 I think if memory serves me right) as per mini and MGB as a temporary measure.
Here I will hold my hands up to a possible relevant error. I fitted the dynamo - nicely marked NEG earth (my 1970 2000TC IS negative earth) started car up everything fine. Only when throwing the box away later did I find the "IMPORTANT NOTICE" at the bottom instructing dynamo must be polarised on fitting. I had not done this, assuming it to be negative earth, but I suppose some marked negative earth will have been repolarised at sometime in their lives? Anyway charging was fine so I didn't worry and assumed everything to be okay.
About three weeks later my daughter (who uses the car almost daily) noticed the ignition warning light on RED continuously, although up until then it had been fine. I found the lead to the SMALL terminal on the dynamo loose, the wire with bare (no solder!) end was swinging loose, the plastic insulation was so brittle it broke in my hands leaving a bare spade on the terminal with no wire attached. New, spade, insulation (and solder!) resolved the problem,normality resumed. Shorlty afterwards my daughter mentioned she had heard a hissing sound under the bonnet when she parked up, which I wasn't unduly worried about as I had just fitted a nice shiny new stainless steel rad cap and thought that would be the culprit.
Now I know it is not the case, but the battery hissing as I presume it is being overcharged :?:
I have attempted to check the voltage regulator and have ascertained that the cut-out (front coil) is functioning - although after reading I now understand this is more of a cut-in and that when the points are closed the battery is then charging. A voltmeter across the battery terminal records 12v with engine dead, rises to about 14v as engine is revved.
The only other thing worth mentioning is I now notice the ignition warning light glows faint red on tickover about 800rpm, extinguishes as revs are slowly increased to about 1200rpm at which point it then momentarily comes back on full very bright red for a couple of seconds before extinguishing again and remaning off. I have not previously noticed this bright pulse as the light actually increases before extinguishing, and again do not know the relevance.
In order to check the charge of the dynamo instructions are to remove the two "B" wires from the voltage regulator, then connect the ignition to the battery in order to start up before taking measurements. I presume this means a wire from +ive battery terminal to +ive coil terminal? I don't want to attempt this without clarification as I afraid to damage anything!!
Apologies for such a long screed but I thought better to explain anything that may have significance to the problem.
Incidentally I have tonight (albeit a bit late) polarised the dynamo as per fitting instructions in the hope :!: it makes a difference - though I doubt it. I am using the car daily myself now to check out the problem.
If you made it to the end, many thanks and all observations welcomed !!
Robin
