new Alternator for a 300E?

[ajs37]

My 1991 300E 24v just broke down (for the first time) - all the electrics started to switch off (radio / instrument panel / aircon etc) and the car just stopped within a couple of minutes and died on me. I put the hazards on - they seemed to be dying as well, but just about kept going!

Rang for help - very lucky that the mechanic turned up within 10 minutes - he checked the battery / alternator - said they were ok - but the car still would not start - so, we connected up the jump leads and it started fine!

He tested the alternator output under load (lights / aircon / rear window heater) and it seemed to be chucking out around 13 volts (as opposed to 13.3 volts with just the engine running) - revving made no difference.

Battery tested good

He thinks the alternator is on it's way out - says it should be delivering about 13.5 volts constantly

Does anybody have any experience of this sort of problem? Is the alternator on the way out?

thanks in advance

Andy

 

[jibcl500]

Regulator pack on the back of the alternator, there are two carbon brushes that wear out, you can buy them new from Bosch centers for about £29 takes about an hour to fit.

My battery is charging at 14.46 volts.

jib

 

[ajs37]

thanks Jib - since I posted this, it broke down again and I ended up getting 'recovered' to a MB dealership - there was no alternative available at the time - none of the autoelectric specialists wanted to look at it because of a possible ECU problem!
So it's sitting there awaiting diagnosis (and probably a hefty estimate!)
It will be interesting to see what they say though.
Cheers
Andy

 

[jberks]

Get it out of there quick!!!!!
a 1991 300E 24v at a dealer - god help you!
Don't get suckered into the 'its an MB dealer so they're the experts' concept. They're not. Ok - I agree - on mine (;ess than 3 years old etc) they probably are but ...
Nobody in that dealership will ever have sat in a 124, let alone worked on one. They certainly won't have any experience whatsoever of the kind of issues that affect a 16 year old E class. Get it shifted to a reputable indie (to whom your car is their bread and butter) sharpish- unless you want a £1500 quote for an ECU you probably don't need.

 

[ajs37]

don't worry - I've had dealings with this dealership before - they know that I won't put up with any crap - I'll wait to see what they say - then I'll shift it if they don't quote a reasonable amount. At the time of the breakdown, I didn't have a lot of choice
Cheers
Andy

 

[television]

Its hard to measure the alternator output when the battery is nearly flat, do bare in mind that the engine runs on the alternator and not the battery, it could just be the brush pack at £10 as Jib says

 

[jibcl500]

Also MB wont change the brush pack they will only change the alternator. Just done the same job on a Range Rover, £29 part, RR wanted £481+vat for the alternator as they didnt supply the brush pack.

jib

 

[ajs37]

Thanks chaps!
I phoned them yesterday afternoon (at 4:30) to get a progress report (after they had promised to phone me) - 'oh - it's just gone into the workshop to be looked at' said one of their reception engineers - 'we'll phone you on Monday to let you know'

Can't wait......
I'll let you know what they say!
Cheers
Andy

 

[Legoman]

for the price they will charge you for labour it would of been worth fitting a new/refurb alternator yourself and keep the change for a tank of fuel , depends if ya like getting your hands dirty though , its not to hard a job.