So, checked voltage wirh nanocom
11.7
Checked charge voltage with tester
11.6
Both by engine running.

Intermittent batterie warning light in dash when revs up and down pressing the pedal to the floor, and display is running wild, telling me door open.
Batterie was charge to full over night, but still get a new one on warranty, so not bothered.

Odered new alternator, so if the old ones is repairable.i may just keep it as spare.
If I ever sell it just makes the value up

so, question, i seen the bolt.on the top, .
The belt seems to can be loosened to get the alternator out.
There is a bolt or nut on the bottom from what I read, how dos that come out?
Is it a straight through bolt to undo and pull out or is it just a a nut?
( Any idea what tool to use idealy?)
Sorry, for the dumm question.
Can't find anything jn workshop manual and unable to see.
Guess the wires come of once is loose?
 
So, checked voltage wirh nanocom
11.7
Checked charge voltage with tester
11.6
Both by engine running.

Intermittent batterie warning light in dash when revs up and down pressing the pedal to the floor, and display is running wild, telling me door open.
Batterie was charge to full over night, but still get a new one on warranty, so not bothered.

Odered new alternator, so if the old ones is repairable.i may just keep it as spare.
If I ever sell it just makes the value up

so, question, i seen the bolt.on the top, .
The belt seems to can be loosened to get the alternator out.
There is a bolt or nut on the bottom from what I read, how dos that come out?
Is it a straight through bolt to undo and pull out or is it just a a nut?
( Any idea what tool to use idealy?)
Sorry, for the dumm question.
Can't find anything jn workshop manual and unable to see.
Guess the wires come of once is loose?
So the battery is dead flat and the alternator is not charging.
Disconnect the battery first and remove the wires from the alternator before removing it
You remove the belt by taking the tension off, to do this I insert a bar in the fork of the tensioner pulley arm and heave, the belt then slides off. Take care to note the belt route as it's not easy to get it back on correctly.
I think it's one through bolt at the bottom, It's a while since I did mine and old age dulls the memory. easy enough job.
While you are at it, check the earth strap from the engine to the chassis.
 
Beat me to it:)
Please don't under estimate how important your car battery is in these cars, they are power hungry vehicles !
I had issues like you and bought 3 new batteries in 1.5 years all claiming to be compatible, until I got one decent one that held the power. Even if the battery you think is new and has all the correct cold cranking amps and power information on them, the quality of the battery between brands is very apparent, don't let others tell you different and stay away from lesser brands, I know this from working as an engineer on battery powered trains.
The battery I found that worked for me was a Yuasa 5000, I also changed the HVAC resistor too as this was preventing the car from going into standby after 16mins, I did this video that may help..

check your alternator is charging correctly by sticking a multi-meter on the battery or cigar lighter, it should be around 13.6VDC and remain at this level even when a load is applied such as headlights etc. The battery once the car goes into standby should be at least 12.6V before you open the doors, you can check this by leaving the meter on the battery. Finally check that your red led light at the gear shift extinguishes after 16 mins of locking the car, if it doesn't then consider changing your HVAC

P.S, if you have been using jump leads these can over time damage your battery and prevent full charge too.
 
Please don't under estimate how important your car battery is in these cars, they are power hungry vehicles !
I had issues like you and bought 3 new batteries in 1.5 years all claiming to be compatible, until I got one decent one that held the power. Even if the battery you think is new and has all the correct cold cranking amps and power information on them, the quality of the battery between brands is very apparent, don't let others tell you different and stay away from lesser brands, I know this from working as an engineer on battery powered trains.
The battery I found that worked for me was a Yuasa 5000, I also changed the HVAC resistor too as this was preventing the car from going into standby after 16mins, I did this video that may help..

check your alternator is charging correctly by sticking a multi-meter on the battery or cigar lighter, it should be around 13.6VDC and remain at this level even when a load is applied such as headlights etc. The battery once the car goes into standby should be at least 12.6V before you open the doors, you can check this by leaving the meter on the battery. Finally check that your red led light at the gear shift extinguishes after 16 mins of locking the car, if it doesn't then consider changing your HVAC

P.S, if you have been using jump leads these can over time damage your battery and prevent full charge too.

13.6 volts is not sufficient to charge a sealed lead calcium battery of the type fitted to cars, 14.7 volts is required. If you only have 13.6 volts, I'm not surprised you went through 3 batteries in a short time.
 
13.6 volts is not sufficient to charge a sealed lead calcium battery of the type fitted to cars, 14.7 volts is required. If you only have 13.6 volts, I'm not surprised you went through 3 batteries in a short time.

It depends on the model and if the car is at idle or under load, At Idle I get 13.6V and under load around 14.2V. The other two batteries I had where sent back for full refund.
P.S I also found that my Merc SL which has two batteries also demands the best battery due to all the electronics and power roof, again I changed 3 batteries on this car until I found that the original Mercedes battery was far superior and not let me down.
 
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It depends on the model and if the car is at idle or under load, At Idle I get 13.6V and under load around 14.2V. The other two batteries I had where sent back for full refund.
P.S I also found that my Merc SL which has two batteries also demands the best battery due to all the electronics and power roof, again I changed 3 batteries on this car until I found that the original Mercedes battery was far superior and not let me down.
At least 14.7 volts it required on or off load to charge current automotive batteries, folding back when full charge is reached to 13.8 volts float charge. If all the connections are good, there should be little or no difference on or off load unless the maximum alternator current is exceeded. The latest cars charge initially at up to 18 volts. Alternators spin at many times crank speed these days and most will give adequate output at idle as is needed to support all the electronic load.
Mercedes do not make batteries.
 
Right. What am I missing here?
Apart a hire truck over x mas now as i need a car everyday.

The 1st pic is the alternator from the car , the second ( newer one is what I bought for the car but seems different on the back
 

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Also the bracket on the top has a 2.5 inch distance but the new one needs a 3.5inch.
I cant get the old one out before I have the new one as I will forget how I got the old one out.
( old age and such )

( sorry I have a motorbike in the shed, I never put back together as I had to dismantle before ordering parts, and bought another instead as it never gone back together )
 

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Also the bracket on the top has a 2.5 inch distance but the new one needs a 3.5inch.
I cant get the old one out before I have the new one as I will forget how I got the old one out.
( old age and such )

( sorry I have a motorbike in the shed, I never put back together as I had to dismantle before ordering parts, and bought another instead as it never gone back together )
Are you sure you ordered the right one?
 
Right. What am I missing here?
Apart a hire truck over x mas now as i need a car everyday.

The 1st pic is the alternator from the car , the second ( newer one is what I bought for the car but seems different on the back
Wrong one matey, dont be tempted to fit it as it will bugger your guarantee and possibly damage your bus:eek:
 
That is exactly the one.compatibel with my car according there website.
It was new but old stock.

I choose that because a new from nearmarch and it others is over 300 bleeding pounds. That's well to expensive for it. Sorry.
The one I got was 100 and acceptable.
 
That is exactly the one.compatibel with my car according there website.
It was new but old stock.

I choose that because a new from nearmarch and it others is over 300 bleeding pounds. That's well to expensive for it. Sorry.
The one I got was 100 and acceptable.
It's not the one kiddo...
Get the part number from the until for me.
 
Wrong one matey, dont be tempted to fit it as it will bugger your guarantee and possibly damage your bus:eek:
So dos this nean I have to fork out the half of the value of a 30 years old car just for one part? 330 quit for a stupid alternator?
 
That is exactly the one.compatibel with my car according there website.
It was new but old stock.

I choose that because a new from nearmarch and it others is over 300 bleeding pounds. That's well to expensive for it. Sorry.
The one I got was 100 and acceptable.
The websites compatibility listing is not 100% accurate, there's usually a disclaimer somewhere.
 
That's all I can get of any numbers
 

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