Smilge

Can I now state for the record....... "Silver Calcium" batteries are in fact lead acid batteries......... Oscilloscopes measure voltage not current........ I could continue....... :P Umm ..... I didn't say they measured current .... I said "Don't risk the scope on high current DC" which meant, don't measure DC with a high current level. and why do they call them Silver Calcium then ...... I'm lost now? :)

How did I guess DOCTOR Seatkid would say no? ........ :) :P Well I'm a consultant ...now get back down to engineering and help scotty!

The inputs to an oscilloscope are very high impedance and, therefore, the current would be negligible. Oscilloscopes measure voltage waveforms. Yes but they also measure DC ..... how do you measure DC levels in BASIC transistor circuits whilst showing the waveform ....tut!

Having had a little break from this post I'm really confused now ...... For the technically minded among our readers..... the output of an alternator is via 6 diodes arranged in a star 3 phase configuration. Therefore to get a short between the output and ground you would require two of the diodes on opposite side of the bridge to fail short circuit. This is highly unlikely. Measuring with an ohmeter would, depending on the meter show open circuit in one direction and medium "resistance" to open circuit in the other direction - this depends on the meter and the voltage it uses to measure "resistance". Agree ..... Translation for plebs.... "You can't measure an alternators health with an ohmeter..." Oh yes you can ...... Those connections should not get hot even at 300 amps So they're super conductors then? Battery disconnected and charged, now 12,72V Sounds good! Ignition on - engine started, voltage over battery 13,84V regardless to load Sounds good too! Too much current going through it. You need to find out where the extra current is going to isolate the fault. Agree ..where is it going? connections, etc. will increase proportionately with resistance. Power dissipation = heat. Yep agree with that too. The alternator is pumping out max amps but not managing to reach the correct terminal voltage which is about 14.5 volts. If that was the case then the voltage regulator's knackered ....... No more than 14 Volts ...... 13.8 is Good. Your battery is dead, on charge it should easily rise to 14+ volts. 12.72 indicates a shorted cell. 12.72 with the battery disconnected ........ OK there's a voltage drop in the cable possibly made worse by a defective battery as seatkid suggests. Bingo!!!! ...arr but short circuit battery cell ...no voltage drop. Captain we have a cell in the battery gone short circuit allowing maximum current flow through the dilethium crystals ...... too much current !!! ..... she cannee take it! Arrrgghhhh! The heat produced has melted the cable and fuse box! ........ Change the cable too Scotty! Aye Aye captain! Oh missed this bit .......... noted that ola said that when he turned on the ignition the battery (ignition) light came on and then went off; it shouldn't do that, it should remain on until the engine is started and there is a charging voltage on the battery (which there clearly is as when the engine is running he has 13.7V across the battery) The reason the light comes on is to indicate the excitation voltage thats being sent to the alternator to get it going ...... once it receives it, it self excites once rotating, and the light goes off. This is part of the voltage regulator circuit and will indicate a charging fault whilst the alternator is being driven.

If its not what familyman suggests then from recent experience with a Rover, sounds like a worn 2nd synchromesh gear ...... have you tried double - declutching to see if it stops the crunching. I think that may confirm your problem if it is the synchromesh but I'm no expert on this gearbox or any come to that ....I'll just shut up.... Hope its something simple matey.

Sorry matey I didnt read the post correctly .... yep I think your right about the movement of the module. Fingers crossed for you mate.

Never mind Ahem ....... battery should be disconnected anyway and what your suggesting when everything's connected back up .... by the time the new fusebox has started to emit smoke its too late. Might be worth finding where the short is first before connecting everything up thats why I suggested testing the alternator feed to earth first. Seen it ...done it.

Oy there's nowt wrong with Allagros .... I had 2 of them :rolleyes: Must admit though he looks a right geek anyway :D

Again thanks for all you excellent comments and just to add to an already heated subject what do you reckon to this? Wife just E-mailed me informing me that she had rung the garage and unless she had an answer today, she would be returning the log book and they could settle the finance on my sons car after having been given advice from trading standards regarding the sale of goods act like chesh100/mikeohope suggested. They asked her if she would like to swap this car for another on her terms and conditions. What do you think? Definately not another dog poo Rover Seatkid before you suggest it ..... :rolleyes:

I understand what you are trying to say Ola ....... What i would do with it disconnected, is to measure the resistance from where the fuse box connects to the alternator to a known chassis earth point (where the negative battery lead connects to the chassis or engine is the best way). If you have anything less than 5 Ohms then you can say you have an internal short circuit through the alternator possibly caused by one or more of the rectifier diodes going short to ground which will allow a very large DC current to run from the battery straight through to the chassis via the fuse. The alternator output will only be there when the engine is running and it initially had the rotor excitation voltage when you switched the ignition on. I haven't got my TIS disc here at the mo ....... could anyone post Ola the correct wiring diagram to help with resistance measurements? Cheers Chris

Haynes manual .... molegrips ..... hammer .... right. Sorry mate not at home .... just wasting your tax paid surfing at work ..... doh! Looks like the weekend then if the garage won't fix it. Thanks matey! :D

Yea ...very fishy..... where's the number for my solicitor time me thinks.

Thank you for all your comments so far. Update: Had a phone call from the garage informing us that the AA independant assessor has put down the problem with the gear box down to fair wear and tear due to the clutch cable snapping! What?! The cable was fine before it left my house. And since when do gearboxes fail due to fair wear and tear at just 57K miles. Awaiting a phone call from the garage after trading standards have contacted them regarding the credit agreement contract "fit for purpose" clause. Hopefully they'll see sense and fix it at their own expense.

No you're not a rotten sod BigJ ........ you're a lovely dad just like me cos I do exactly the same except that I threaten them with ME washing there hair in real poo!

It is difficult Boozey particularly with a baby and only one adult driving ........ I managed to persude the Mrs to put the baby in a rear seat behind the passenger seat when she was on her own and strategically placed another rear view mirror so she didn't have to keep looking behind her. Even now when I'm on my own I stick the older kids in the back. Front seats ...... grown ups or awkward teenagers only!

Ola ..... I cant see the positive connection to your battery being suspicious .... it's either connected or it isn't and if you had an intermittent connection you would have noticed it well before the fuse box melted. This sounds to me like a short circuit to the chassis straight from the battery via the fuse. One path is an internal short through the alternator so it might be worth checking this before you fit the new fusebox on monday and have the same thing happen again.

What do you mean ...it is already!!! :D :lol: :D

Oh don't remind me please ......... tut :wacko:

The handbrake lever should go all the way down whether or not the pads or cable are worn. Sounds like something is physically preventing the lever from going all the way down. Does the ratchet mechanism look OK and is there anything stuck in there? Are the rear brake cable(s) seized or catching on something? Hope this helps.

Welcome Woolmer ...... dont be scared ...... whats up with it then? ..... Try starting a new post with the problem. Eagerly awaiting.

Buy yourself some decent pads and do it yourself. I'm a little fussy when it comes to brakes particularly in the cleaning and greasing, whereas garages tend to "wop" the new pads in and away you go. You could get a good set of discs and pads for that price and once you've learnt to do them once with help from a freind, you'll realise how easy it is.

Still haven't stuck the AA stickers on it yet though T.... :wacko:

Welcome from me to ola ...... can you confirm that your battery is dry? ..... does it have any electrolyte (fluid) inside each of the cells? If it hasn't then do not try and charge it. If it has and the battery is a "low maintenance" type and it has gone totally "dead" then it will be useless even if it appears to charge up. Get yourself a new battery, preferably a Silver Calcium type due to the SMART charging as richyrich suggested and then when the car's running, you can check the DC voltage across the battery terminals to see if the output from the alternator is OK, as suggested by Seatkid. Good Luck.