It ain't easy fixing Green (Benz that is)

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It ain't easy fixing Green (Benz that is)

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It ain't easy fixing Green (Benz that is) - 1/22/2008 1:44:14 PM

imcgarvie

Posts: 8
Joined: 12/28/2007
Status: offline

Hello again,

First, thanks to all who have responded to my previous questions.

Here are a couple more I need help with.

First, on my older (gas) cars, I was able to determine if the alternator/generator was working by disconnecting the battery while the car was running. If it kept on running, the problem was elsewhere. Will this work for a 1979 300SD diesel or do I have to take the car to a shop to get my system checked?

Secondly, as this was a purchase from Green Benz (you can stop laughing anytime) I have reason to believe it was a compilation of several vehicles. I have been able to find three VIN tags. The first two (one on the drivers door frame & the other on the left windshield frame) are the same. The third (next to the hood lock mechanism) is different. The first two are 116 120 12 002722 and the odd man out is 116120 12 02665 7. Is this usual for this model of Benz and are there any VIN placements I have missed?

Thank You once again,
Ian

Post #: 1

RE: It ain't easy fixing Green (Benz that is) - 1/22/2008 9:50:51 PM

snanceki

Posts: 2396
Joined: 12/11/2004
Status: offline

Its not good practice to determine if an alternator is working in that way.

To determine if the alternator is working (correctly) place a voltmeter across the battery terminals.
With the engine NOT running you should see something in excess of 12.5v.
With the engine running it should be more like 14 to 15v.
Ideally you need to put an ammeter in series with the alternator output to determine current rather than voltage.
Some meters have a device that can be clamped around the insulator alternator output lead and can determine the current being generatoed without breaking the circuit.

stuart.

(in reply to imcgarvie)

Post #: 2