car died, think alternator, please help.

More threads by irvine

irvine

New Member
Messages
26
Points
0
Location
Maroubra, Sydney
hey everyone I need help and sadly this is my first post,
ive just had my first breakdown and I'm stumped as to why its happened....

so today I left the side lights on for a couple of hours by accident, the car didn't start as usual and struggled like it would from a low battery which was to be expected. so I waited a good 5 mins letting it idle then dropped my girlfriend off a good 15 drive away, on the trip the battery light stayed on and when stopped at traffic lights using the indicators it felt like it was going to stall. but after about 20 mins of driving the light went out and it felt good again.

once home I turned the car off and tried it again to see, and it didn't start.... it did bring on the dash lights and prim the fuel pump but couldn't turn the motor over. so got a jump start and it fired up instantly.

i tested the battery and it was 11v, let it run for a wile and tested it running to check the charge and it was dropping now to 10v. obviously that points to a stuffed alternator.

am i right?

other question is what alternator would i need? the cars a 1974 280SE.

huge thanks for any info.
neil.
 

c107

and 111/126
Moderator
Messages
2,316
Points
124
Location
Sydney
Hi Neil,

Welcome to the forum.

Could be the alternator, or could be your battery has a dead cell and is not able to hold a good charge.

Either way a voltage meter could help here to see what sort of output you're getting from the alternator when the car is running and if you rev it up a bit what it changes to. If you're seeing low voltage when running then it might just be the voltage regulator on the back of the alternator which is quite easy to change.

If you have a dead cell, you'll probably see decent voltage when running but it will go back low again as soon as you turn off the car. You can take the battery to a battery shop or somewhere like supercheap and they will test it for you as well.

I had a battery with a dead cell and it behaved somewhat like what you're describing. Battery didn't have the juice to start the car, but was ok to keep it running once going. Luckily this car is a manual so was able to roll start it if it stalled. Old british car so the lucas starter was good at exposing weak batteries.

Bryce
 

BenzBoy

Master
Messages
6,961
Points
164
Location
Sydney - Centre of Civilisation
I agree with Bryce - you do need to diagnose the problem which could be a faulty battery through to a voltage regulator or the alternator. It could even be the power lead is faulty. My recommendation would be to have it all tested by someone reliable such as http://www.autoignition.com.au/
In general they are spot on with their diagnosis.
Regards,
Brian
 
OP
I

irvine

New Member
Messages
26
Points
0
Location
Maroubra, Sydney
ok so update from todays tinkering...

I pulled the battery and all relative hardware, I could not believe the amount of dirt grim and caked in oil on the wiring connections and earth strap from the alternator. ive cleaned EVERYTHING and sanded all nuts, bolts, screws, lugs and connections.
the regulator was a mess, caked in grime and as everyone suggested was worn substantially. ive put everything back check all connections, even refitted the regulator and what do you know, it fired up no problem. I tested the voltage of the batter before I connected, it read 12.3v and connected with the engine on load it was reading 13.8v.

some pics below to show the state of the connections and regulator:

terminal block under battery tray:
W116 by Neil Irvine, on Flickr

connections inside alternator:
W116 by Neil Irvine, on Flickr

alternator cables/connector:
W116 by Neil Irvine, on Flickr

and the regulator in question:
W116 by Neil Irvine, on Flickr

i really want to change the regulator asap as from the pics its stuffed, i dont trust how long its got left. problem is the suppliers near me only stock bosch regulators and they need the part number.

can some one please give the part number i need??? its for a '74 280se...

thanks for all the info guys,
neil.
 

Oversize

Master
Messages
5,170
Points
181
Location
Melbourne
Give the engine etc a good steam clean with a hot pressure washer (you can hire them from a couple of places) and degreaser, but be very careful to avoid the delicate parts.
 
Similar threads
Thread starter Title Forum Replies Date
WGB Something died in my car. Interiors 35
c107 Car industry trends towards SUV Articles 4
Oversize 500SLC CanAm Race Car Motorsports 18
Oversize W126 Concept Car Mercedes W126 5
Oversize 450SEL Bash car for sale Motorsports 2
c107 Virtual car boot sale Gumtree/eBay/Facebook Listings 1
I MC hammer's car Mercedes W116 1
Styria Rervealing Car Reliability Assessments Websites and Links 1
Oversize Red Pig Tribute Car & Info Motorsports 1
c107 Car clubs and long defunct brands Articles 0
S used car trade in values Articles 45
B My car of the week. Talking Torque 4
Oversize Australian Classic Car Mag 12/2013 Articles 3
c107 USA Car shows/museums Car Show Photos 1
Oversize Mercedes Benz Official Classic Car Sales??? Websites and Links 1
B Horrible Car Repairs Websites and Links 1
B Starting a car after 6 months idle Mechanicals 8
motec 6.9 Dame Patie Menzie's car Gumtree/eBay/Facebook Listings 0
motec 6.9 DTM 107 race car for sale Mercedes R/C107 3
B Rock 'N' Blues Concert and Car Show Car Show Photos 8
c107 Beige/Tan Luxury car interiors are dead Websites and Links 2
c107 Luxury car depreciation Talking Torque 1
Oversize Concours Secrets & How To Polish Your Car Exteriors and Body Repairs 9
Styria 6.9 Listings on Car Sales Gumtree/eBay/Facebook Listings 4
S Vintage car Rally Websites and Links 1
c107 modern car sound system upgrade Interiors 1
c107 ACT German Car Show 2017 Car Show Photos 4
Styria Hitler's parade car Cars of Yesteryear 0
B No new car... Talking Torque 12
c107 Car of the week Gumtree/eBay/Facebook Listings 1028
c107 Parts car for BenzBoy Gumtree/eBay/Facebook Listings 2
Oversize When to Sell and Buy Another Car? Talking Torque 6
c107 W116 charity bash car Gumtree/eBay/Facebook Listings 0
260ebenz Classic car videos Websites and Links 0
260ebenz Car detailing tip Technical Information 2
motec 6.9 Battle of Waterloo car show Canberra Talking Torque 4
motec 6.9 Survivor Car Magazine Articles 6
R Private Fleet Car Broker Recommended Suppliers 1
260ebenz Classic Mercedes & car videos Websites and Links 1
B Recommended car carrier? Recommended Suppliers 7
Styria Selling your car Talking Torque 7
B Ant's new car Talking Torque 51
260ebenz Classic Car Restos Websites and Links 0
260ebenz 450SEL for sale- bash rally car Gumtree/eBay/Facebook Listings 4
Oversize My White 450SEL Parts Car Mercedes W116 11
motec 6.9 Best car sounds vol 5 Motorsports 21
Michel More from Bonhams Mercedes Auction-pedal car Gumtree/eBay/Facebook Listings 3
motec 6.9 Funny car add Gumtree/eBay/Facebook Listings 4
B Wanted: Turbo diesel car Gumtree/eBay/Facebook Listings 15
motec 6.9 Lotto Car for Mark Gumtree/eBay/Facebook Listings 19

Similar threads

Top