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Daddles
2nd February 2007, 12:31 AM
I need an electronic hero to have a look at my MGB. She has a problem with the battery going flat when ignored for a week or so (and yes, the battery is now knackered but mainly because I keep recharging it with a cheap charger) and the horn has for many years refused to give the legally required 'toot'. There are, of course, the attendant problems of dealing with wiring devised by the British Auto Industry supported by products supplied by the Prince Of Darkness (Joe Lucas), but if you are familiar with these beasties, well I'm sure there is some therapy that can help :rolleyes:

Anyone who genuinely knows about this stuff like to have a look at her? I can offer rates that vary from a supply of your favourite intoxicating beverage through to proper, commercial rates - I'd just like to see the profit go to a forumite.

Cripes, I'll even let you tell me what a good job I'm doing on my wooden boat :D

Richard.

a PM to arrange an appointment is fine by me, you don't have to expose yourself to the ridicule of the great unwashed

Schtoo
2nd February 2007, 01:05 AM
There's only one real soluition.

Starts with an 'S' and ends in 'emtex'...

Gra
2nd February 2007, 01:17 AM
Daddles,

having been there done that (Had to sell it.... damn I miss that car....). before you go pay someone to fix it, have a good look at your bullet connectors. They rust and stop passing electrons. Go around and clean them up, give them a bit of copper grease (I think that was what you are supposed to put on them) and see what happens,

Oh and drive it more often, they don't like to sit, they get grumpy if you don't drive them:D:D. Of that I am not joking, used to have the same problem, if it wasn't driven for a week, she was a b@#$h to start and run like c@#p for a while, she would then clear her throat and run beautifully. It was just her way of telling me I had neglected her.

Have fun with her, they are a great little car

Daddles
2nd February 2007, 08:54 AM
Yeah, she doesn't get driven much - bit of a problem when you've got two kids and a dog in the car as often as I have. Theoretically, she should be for sale to cover the latest Family Fraud expenses but for some reason, I never get her clean enough to sell :D Looks like she might be staying in the family which is a bit of a bugga because she's red, a rubbernose, has steel wheels and is a yankee convert - why couldn't my 'keeper' be a british racing green, aussie built, Mk 2? Ah well, there's always the V8 conversion to dream about.

The Little Red Rollerskate and her predecessors (http://www.users.bigpond.com/richardspurling/mg.htm) :D

Richard

craigb
2nd February 2007, 08:58 AM
A yes, "Lucas, Prince of Darkness". :wink: :D

echnidna
2nd February 2007, 08:59 AM
Sounds like there is a small leakage current in the car.
Is there a boot lamp or bonnet lamp in the car?

Daddles
2nd February 2007, 09:04 AM
Sounds like there is a small leakage current in the car.
Is there a boot lamp or bonnet lamp in the car?

No lamps but I agree about the leakage. The trick'll be finding it. Sorry, when it comes to electrics I'm comfortable with the smoke theory but not much beyond that :(

Richard

echnidna
2nd February 2007, 10:00 AM
Disconnect the battery and connect a 5 watt globe between the battery terminal and the wiring.
If theres a leak the globe will light up. (unless its a minute leak then you would use a meter instead of the globe)
Disconnect various things one at a time until the globe goes out.

Does the radio work through the ignition?

Daddles
2nd February 2007, 01:54 PM
Grumble grumble grumble.

I put the brute on charge last night ... and forgot to make sure the plug was in properly so nothing got charged. Been charging her today only the ruddy charger's acting up so it's not working as well as it might. She's been sitting for a bit so the fuel pump points have seized and there's no way she'll start without that clicking and I've poven before that the old 'whack it with a spanner' doesn't work - just keep trying is the best option (short of pulling it apart), which is fun with a flat battery.

Stuffit. I was going to give her a wash and vacuum this arvo but I think I'll watch the cricket instead.

She's a wonderful, reliable little car when used with some sort of regularity, but I've been ignoring her and she's got the ##### with me. Like all wimmen, the trick isn't finding the cause of the problem, it's jumping through enough hoops first

Richard

rrich
3rd February 2007, 06:09 PM
Richard,
A couple of things....

You've said that the horn doesn't work. Why? Did it stick in the on position and you just pulled the connectors of the horns to stop the noise? Well, it could be the horn relay draining the battery. See if you can fix that first.

The battery could have a high resistance short between the plates which is draining the battery. A new battery usually solves that problem.

What about the under bonnet, in the boot and glove box (?) lights? Are they on all the time? Any of those would drain the battery in about a week.

Is your MGB the one with the battery in the back of the passenger compartment? There was a problem where if the terminals were corroded, there could be a slow drain on the battery through the corrosion. (I can't remember if that was the MGB or the Datsun/Nissan copy or Fair Lady.) Clean up the corrosion with baking soda and water.

Finally, if you have a stock radio, this is probably not the case. Some replacement radios, especially ones that require a positive earth to negative earth converter, have a "Memory" line. This is a constant drain on the battery but it is to keep the preset radio stations in memory. Sometimes these circuits fail and cause a higher than normal drain on the battery. The polarity switching device complicates things also.

Daddles
4th February 2007, 12:11 AM
Richard,
A couple of things....

You've said that the horn doesn't work. Why? Did it stick in the on position and you just pulled the connectors of the horns to stop the noise? Well, it could be the horn relay draining the battery. See if you can fix that first.

The horn doesn't work because it's a miserable sod that likes picking on me :D It used to, now it doesn't, and doing the usual look for loose connectors hasn't achieved anything. She's got a Momo wheel on her and that caused some drama with the horn in the early days (button in the centre of the wheel, not on the stalk) but I had it working for at least a couple of years. Yes, I've checked that as much as I can. The answer could be simple, or it could be a prize **insert word that the naughty word filter doesn't like**.


The battery could have a high resistance short between the plates which is draining the battery. A new battery usually solves that problem.

Nope. It's got the current battery because the previous one used to go flat all the time and died from all the recharging. Guess what's happened to this one :roll: Mind you, this battery has lasted six years so I'm not about to complain about it. But yeah, there's evidence that the leak predated this battery ... and was there when the horn still worked too for that matter. The battery is rooted though (see later) and a new one will alleviate some of the problems.


What about the under bonnet, in the boot and glove box (?) lights? Are they on all the time? Any of those would drain the battery in about a week.

Nope, no lights. Doesn't mean there isn't a fitting somewhere doing the dirty on me, but no lights.


Is your MGB the one with the battery in the back of the passenger compartment? There was a problem where if the terminals were corroded, there could be a slow drain on the battery through the corrosion. (I can't remember if that was the MGB or the Datsun/Nissan copy or Fair Lady.) Clean up the corrosion with baking soda and water.

All the B types had the battery behind the seats. In the early ones, it was two 6V batteries and those really lasted well. Then they went to a single 12V and the system immediately became marginal. There is a little corrosion on the terminals as you'd expect but they've actually lasted very well (it's better than the Falcon). I'll clean all that up when I fit the new battery


Finally, if you have a stock radio, .

After market radio, but that doesn't mean it isn't the problem. It's one of those where you can take the facia off so that thieves are less inclined to steal it, and being relatively elderly now, you sometimes find yourself wriggling the damned facia trying to get it to work. It's wired through the ignition. Goodness knows how well it's been wired, but this is the first MG I've owned where the wiring bears some resemblance to what the factory put in. There was a fetish for a long time of rewiring the poor cars whenever something appeared odd. The fix for all this was usually to get rid of the extra wires and return it to the original set up.

Thanks for the thoughts. It's interesting that no electrician has offered to take a look at her. Come on boys, MGs aren't that scary ... well, not to a brave man :o

She wouldn't start at all yesterday. I finally gave up and called the RAA. The bod hooked her up to his super backup battery and away she went - it would appear that the starter was drawing all the ten or so volts on offer and leaving nothing for the fuel pump. Not a problem. Looks like my battery is genuinely rooted so I'll go looking for one in the next few days and try to drive her a bit more often. The horn does need to be fixed, even if I never sort out the slight drain on the battery.

Richard

journeyman Mick
4th February 2007, 03:32 PM
Richard,
aaah the joys of owning/working on British motor cars. Never owned an MG but had a loan of one for a few weks while the owner was overseas. First time I drove it the electrical system died completely and I had it towed to the autoelec where it spent a few weeks. Played with landrovers for a while and we used to just remove the entire wiring loom and build a new one. This alleviated mot problems and replacing the prince of darkness' spawn witn offerings from herr Bosch where possible fixed the rest. British car designers should be sentenced to 10 years labour in a workshop repairing their cars so they can see how silly their stuff is.

Examples:
Austin truck: replace wheel cylinders as they were corroded. Not a problem until I went to refill ther master cylinder. Mastrer cylinder was under the floor with the pedal swinging directly off it. About 30mm clearance between floor and resevoir which had a metal cap held down by a swinging bail. It was barely possible to remove the cap and once removed I couldn't fill it, even with a length of hose and a funnel. Had to hole saw an opening in the floor and make a cover plate for it.:((

Series IIa landy, want to remove the master cylinders? Unlike every other manufacturer who use studs or captive nuts as one end of the fixing British engineers decided that they'd use a nut and bolt, thereby requiring two operators to do a one man job.:~

Series IIa landy again, once you've rebuilt the brakes and need to completely flush and bleed the brake system you'll find that the front brakes won't bleed. Tried one way bleed valves, pressurised bleeding rigs and vacuum gizmos. Turns out the bleed valve is at the lowest point on the twofront cylinders, rather than the highest where it should be. Solution? Remove the drum, shoes and unbolt the backing plate and swing it around so the bleeder is at the top where the air is.

I could go on and on but I don't want to raise my blood pressure.:wink:

Mick

echnidna
4th February 2007, 03:41 PM
Those pommy cars were made to train apprentices on so that as tradesmen they'd appreciate working on yanktanks.

Though customlines were a bit of a beast for removing starters.

The worst car I struck was a Lamborhini with a tranverse mounted rear v8.
Had to remove the engine to get the starter motor off.