Charging problems, I need help!
Hi everyone and seasons greetings to all,
Some of you may have seen my posting on the exploding battery and this is the ongoing saga from that problem.
The 300GD is a 460 1985 swb and seems to be fairly standard.
The vehicle was taken to Merc for the warranty replacement of faulty alternator and exploding battery.
We are on the third battery and alternator and now plus a repaired part of the wiring (not sure what they have done yet) they say it has nothing to do with the alternator. The options I have are to continue to pay them £75 plus vat an hour with no guarantees or take to my auto electrician at nearer £30 plus vat an hour!
I thought to start with I would post this message to see if anyone has had any of these problems or has any idea as to what I should try first?
The big question is:-
What would be influencing the charging system to charge at 18volts and not the normal which I think should be around 14?
Many thanks for trying to help and I am sure I will be back on the road soon, 3 days out of a month of ownership is a bit trying for anyone!
Murph
Murph,
Sorry to hear you’re on going problem.
This just demonstrates how useless main dealers are at dealing with rudimentary problems. If they can not plug a diagnostic tool in and be given an answer they are stumped. Even when they are given an answer they simply follow the changing bits process (at your cost) even if logic says the answer is wrong.
Anyway, did they replace the entire alternator, including the regulator? There should be no way the alternator gives an output of 18V. I can not believe they claim the problem is not the alternator/regulator, where do they think the 18volts are coming from?!
The regulator is the box bolted on to the end on the alternator. I would think it must be this that is faulty.
Get it from the MB dealer (who have obviously gone beyond their level of incompetence)and take it to an auto electrician. The charging system on a 460 is so simplistic it should not take much to get it sorted.
Good Luck and let us know how you get on.
Russ
i would also suggest you call mb customer support and vent your anger at your dealer for there incompetence.
I took my US alternator to this company they rebuilt it completely including sand blasting and repainting it to look like new for a total of £55 give them a call PCM services 01304 829990
Sounds a bit like you did something really bad in a past life and the almighty one is getting his or her own back!!!
Umm this is a weird one!
When the new alternators have been fitted have they initially operated correctly E.G. output approx. 14.5V dropping down to 12.5V as the battery reaches it’s fully charged state?
Are they then subsequently found to be faulty after a period of time? E.G output 18V.
Even though it sounds implausible that 3 have been faulty I still believe the regulators to be the culprits.
Alternative maybe a wiring fault resulting in very high current passing through the alternator and subsequently causing the regulator to fail. The fact that the MB dealer has repaired / replaced some wiring may point to this. However the piece they have replaced may not have been the primary fault.
Hi Murph
I have a simillar problem with my 300gd 463. The wife took it away xmas shopping and the battery boiled, it has also blown three or four bulbs. when you are driving at night the lights go dim and then return to normal. The volt meter reads 17volts at tickover, so I am going for the voltage regulator first, as soon as I am sober enough, or when the shops open again.
Happy xmas and a good new year!
Bill
Murph,
Are you sure it was 18Volts? Or was it charging at 18Amps?
If 1 cell of the battery is U.S it will continue to take amp's and eventually boil.
Russ
Hi murph. And a good new year to all!
Just to let you know that I renewed the voltage regulator 2 days ago and all seems to be well. The lights are steady at night, the battery dosn't get hot anymore and no more blowing of the bulbs. Charging at 14.3v and not 17v as before. Price - Merc £ 46+vat. Lucas/Bosch £25+vat. So there is a wee saving there. :D
Bill
Be warned, if you have a 463 series and the battery has blown or boiled the acid finds its way inside behind the glove box and corrodes electrical wires and relays. We found this out last year in france off-roading. The diff locks would not work so we had the glove box out to test the relay and this was rotten through becuase the battery acid had dripped down and eaten its way through the relay Luckily thats all. Check all wiring behind the glove box and any relays to make sure everythng is ok. If the acid has found its way into anything this may be something to do with the overcharging, there may be a short.
Murph,
Can you give me contact details for garage you recommnd?
Thanks
Rob
Hi everyone,
Thanks for your replies.
The 3 alternators have been new Mercedes parts as have been the regulators and the aditional regulator bought as a back up.
I too thought it was a simple system however this does not seem to be the case.
Has anyone any ideas of what sort of outside influence could cause such a problem?
Thanks
Murph
PS I guess I will be calling MB for more help and there opinion etc