Wiring an earth to your car

Still unacceptable today, the indications are that the wiring was internal to the car, plenty of attachment points or other wires for cable ties or non penetrating clips. The owner said he had a lack of time not the fitter, no excuse

My sentiments exactly! 

I would query your definition of top sparkie, in years gone by the manufacturer learnt that the  welded earth stud was preferable to the self tapper. Just because it was always done that way doesn't make it right today, it is unacceptable to perforate the various body protection systems.

It wasn't my definition, I was only 16 at the time. He was recognised as being the best in the industry in the region at the time, e.g. "Need electrical work done on your car? Take it to Ronnie, he's the best around..." I didn't feel the need to give a full definition at the time but I'll be more carefull next time.

EmilysDad's concern seemed to be rust occurring due to the hole being drilled for the self tapper. If the cable was run 12" to the correct earth stud, self tappers would still have been used for the cable clip(s) which is required every 6". Using cable ties would be considered 'shoddy'.

By his own admission, his lack of time and effort may have been a contributing factor. Had he asked the car manufacturer's dealership to do the job they may well have used the proper earth studs and they would have charged through the nose for the privilege. Instead he chose the cheaper option and later complained because it wasn't done to his expected standard.

I was merely pointing out that this happens all the time and his car won't crumble into a pile of rust at the side of the road because of it.

In short, read my first post...

I don't think for a minute that my car will end up as a pile of rust due to the extra drilled hole, it's the fact that i have an unessessary hole! As Dartman says, there'll be plenty of things to attach suplementary wiring to at the back of the car ......... & I'd question the spacing of every 6" :-? I'll set to with a tape measure. 

I did my apprenceship with a top car sparkie many moons ago and this is normal practice. I wouldn't worry about it.

 EmilysDad's concern seemed to be rust occurring due to the hole being drilled for the self tapper. If the cable was run 12" to the correct earth stud, self tappers would still have been used for the cable clip(s) which is required every 6". Using cable ties would be considered 'shoddy'.

By his own admission, his lack of time and effort may have been a contributing factor. Had he asked the car manufacturer's dealership to do the job they may well have used the proper earth studs and they would have charged through the nose for the privilege. Instead he chose the cheaper option and later complained because it wasn't done to his expected standard.

I was merely pointing out that this happens all the time and his car won't crumble into a pile of rust at the side of the road because of it.

Any additional hole made in the car body work which is not adequately protected against exposure to the elements will allow the onset of corrosion at that location, irrespective of the material the fastener used  is made from. A stainless steel self tapper may not corrode.... but sure as you breathe the bodywork will start to rust

As for clipping the cable run every 6 inches that is fine; but there are excellent adhesive backed cable tie mounts which are perfectly acceptable for internal use. Had these been used instead of a self tapper then there wouldn't be a problem and  would have provided the necessary location for a cable tie without the requirement to unnecessarily damage the car structure. If self adhesive is not up to a tradesmans "standards.".....!!!!!!!!; then there are plenty of PU type adhesives which could be used to provide a sturdy means of attaching a cable tie mount.   Doing this would require very little extra cost but need a little time for cleaning the area prior to applying the adhesive and a little time to wait for the adhesive to cure

In my eyes (and I guess that EmilysDad would agree) it is laziness on the part of the installer who cannot be bothered to use something that may take a little longer in time but provide a much more acceptable outcome... like the use of scotchlock cable connectors rather than the preferred method of soldering. 

Scotchlocks damage the cable insulation to make the circuit and if the incorrect size is used will cut through the conductor strands too....but they have been used for ages.... but still doesn't make it right....   just quick

I see a common thread here.....get it done as quick as possible and hope you don't get a customer who gives a damn

While the car may not crumble to a pile of rust immediately due to laziness on the part of the "tradesman" the fact remains that damage has been done to the car body which will cause rust to form if the edges of the hole that has been made have not been protected and if the screw is being used as an Earth point then you can be certain that it would not have been protected. I would doubt if there was even any petroleum jelly applied.

...... Instead he chose the cheaper option and later complained because it wasn't done to his expected standard. 

......

I don't think 'expecting standards' are applicable here. I expected it to be done correctly, and by that I mean the carrect earth studs provided by Mercedes.

As for cost, the 'cheaper option' was £114 for the addition of a half a dozen cables & a voltage sensitive relay (and a hole ) ........ not exactly 'cheap' 

If you have ATC fitted make sure you have 20amp fused supply fitted from battery as when mine was changed over from twin to single electrics for my new van with ATC whilst there was an indicative current reading it wasn't enough to light a 1watt bulb. The twin electrics on my new car were fitted by a well known towbar specialist & was returned to them for conversion. I had to take it back twice before the correct feed was fitted . I should add that the towbar was subcontracted to the specialist by the main dealer due to a long delay before they could fit one.

I should add that the towbar was subcontracted to the specialist by the main dealer due to a long delay before they could fit one.

From personal experience 

They mostly tend to do that because it allows for buck passing when the pre-installed wiring on the car isn't up to spec and you find there is no feed to the fridge or battery charging circuit.... also allows for the use of the dreaded scotchlock connectors and other dubious practices which are apparently "the way its always been done"