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Worth replacing battery after new alternator?

ItalianTuneUp

MB Enthusiast
Joined
Nov 20, 2013
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1,356
Location
Hampshire
Car
S320CDI
I had a new battery fitted a year ago, but I've had a slowly failing alternator which has just been replaced with a new one recently.

I'm wondering whether the old alternator could have caused the battery to charge badly / insufficiently, leading to a less than perfect battery.

Even after waiting for the glow plugs to extinguish, ignition only occurs after the engine has turned over about 5 times or so (quite cold weather), but certainly not immediately. I had the glow plugs replaced a year or so ago too. I can live with less than immediate ignition, but I was curious. Any ideas about the ignition delay? At random times driving along the motorway, the glow plug symbol occasionally lights up on the dash. Glowplug control unit?

And would you replace the battery for a new one, now that there is a new alternator?
 
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I do agree that regular poor charging will have somewhat deteriorated the new battery, but perhaps no so much as to merit a replacement.

I would firstly see if the battery revives once the new alternator is given a chance to properly charge it.

Then I would take it to a car electrician to run a load test.

If all the indications are good, I would keep the battery.

With batteries these days lasting five, seven, or even ten years, you might simply end-up with a battery that lost a couple of years of life but might still be good for another three-four years.
 
If the load test is good I would put it on a conditioning charger such as ctek or Accumate which will get it back to as good as new
 
Thanks Mark.

I would firstly see if the battery revives once the new alternator is given a chance to properly charge it.

It's been a month or so now with quite a few long journeys.

Then I would take it to a car electrician to run a load test.

If all the indications are good, I would keep the battery.

Maybe I will try this next. How much should I pay for a load test do you think?

I do agree that regular poor charging will have somewhat deteriorated the new battery, but perhaps no so much as to merit a replacement.

With batteries these days lasting five, seven, or even ten years, you might simply end-up with a battery that lost a couple of years of life but might still be good for another three-four years.

It is a good battery, silver varta, so it should hopefully last a while.
 
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If the load test is good I would put it on a conditioning charger such as ctek or Accumate which will get it back to as good as new

Thanks flango. Does this conditioning need to be done one off, or as a regular thing?
 
ItalianTuneUp said:
Thanks flango. Does this conditioning need to be done one off, or as a regular thing?

You can do it on I did this on my 208 then I leave it plugged in as a maintenance charger I've had the car 7 years and not changed the battery yet and it's never failed (now that's tempting fate) lol
 
Lol, good luck! I don't have a garage so I would have to disconnect the battery first. That silver Varta is massive and heavy!
 
ItalianTuneUp said:
Lol, good luck! I don't have a garage so I would have to disconnect the battery first. That silver Varta is massive and heavy!

Extension cable? I did mine originally in the drive it's only a low amp conditioning charge
 
Yes, I suppose I'd have to run an extension cable across the pavement and watch out for trippers to avoid any claims ;)
 
What sort of money are these battery conditioners?
 
Guys can anyone advise please? I posted the below yesterday but only one reply to date

Hi folks, my first post on here so be kind.

I have 1998 Clk 320 coupe.

About two weeks ago I noticed the abs bar warning lights come on. It drove fine so I just left it. I read a few posts saying it was due to a build up on the censor etc.

Anyway, today after a cold week I had been driving for about a mile when the 'battery charge' read on the dashboard, but worryingly the power steering seemed to cut out!!

It was drivable so I managed to drive the rest of the way to work where I put the battery on charge.

Question 1 - top right of the engine bay I found what I think is the positive connector, the nip which is best described as a rounded large bolt about two inches further in, is that the best neg port?

Anyway 10 hours later I started the car, it started fine but exact same problem!

As I was driving it was blowing cold air, wouldn't warm up, so I turned air off, radio off etc an for about two miles it drove better, steering loosened up a little.

But that's where it ended, all of a sudden the lights went out an I lost power.

I crawled to a lay by and left it put. Enough battery power for radio and lights but it won't start, I've tried jump starting it and nothing.

From my very inexperienced views I have done or noted the below:

There is no spark when I connect the terminals, not even a direct cross of +/- is this likely to be the two connectors? Hence why it is not charging or allowing a jump?

Also silly I know but I can't actually find the battery! Just them two connectors I was tying to describe!

Points I need to know really. Is this likely to be a battery problem or more serious of power steering pump etc?

Any help would be much appreciated as my car is currently sat on a bypass ( in liverpool!) so might not have any wheels left if I don't fix it soon!

Thanks

Adam
 
Hi Adam, it sounds like your alternator and thermostat need replacing from what little I have read.

My battery is on the driver's side of the boot, lift up floor covering in the boot. Maybe yours is in the same location?
 
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Italian tune up thanks,

Do you know approx cost of these? Il be honest I bought the car few months ago I just need it to get me through too May because I'm away for 4/5 months. So if it's not expensive il get it done if it is, then Id prob try and just get by with sharing the Mrs fiat bloody 500 :-(((
 
Can't say for your car, but for my car a new alternator including fitting and vat was less than £400, and thermostat less than £100.
 
Italian tune up thanks,

Do you know approx cost of these? Il be honest I bought the car few months ago I just need it to get me through too May because I'm away for 4/5 months. So if it's not expensive il get it done if it is, then Id prob try and just get by with sharing the Mrs fiat bloody 500 :-(((

So it's cough up circa £500 or it's the Fiat 500 for you! What's it gonna be? ;) :dk:
 
Italian tuneup how much was your alternator?
 

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