10 replies to this topic

[monster_mini]

Hi all, just after your thoughts or experiences on this.....

http://www.ebay.co.u...984.m1423.l2649

Too good to be true or not?

Have some welding to be done on a friends mpi soon and wondering if this will mean I can do it without disconnecting the battery:)

Cheers
Nick

[R1mini]

Disconnect the battery it will save you £26.98

 

David

[freshairmini]

Is the battery really that difficult to disconnect? 

[sonikk4]

I disconnect the battery and alternator. I have also welded other cars with multiple Ecu's etc and no adverse affect whatsoever. And that was with disconnecting nothing at all.

[myredmini]

As above, just disconnect the battery and unplug the alternator to prevent damage to the regulator.

[KernowCooper]

Thats the normal way battery disconnected and alternator plug out, if its a ecu car then I slip the master plug off for the time it takes its a safety net as welder produce voltage spikes at the point of the strike up

[Shifty]

On the mpi I remove the ecu and the srs unit under the rear seat. Better safe than sorry!!

[charie t]

I disconnect the battery and alternator. I have also welded other cars with multiple Ecu's etc and no adverse affect whatsoever. And that was with disconnecting nothing at all.

You use a good earth point close to the area being welded, but how many with blown ecu/alternator/batterys, use the subframe or exhaust or a component close by?

[Tamworthbay]

I disconnect the battery and alternator. I have also welded other cars with multiple Ecu's etc and no adverse affect whatsoever. And that was with disconnecting nothing at all.

+1 and the mini without disconnecting the battery, not on purpose just forgot. Never had a problem but I may have just been lucky.

[tiger99]

The battery is almost completely irrelevant. It is only solid state electronic equipment such as alternator, audio system, engine management computers, etc that is at risk, and even then only if stray voltage above at least 0.7 volts gets to where it should not. i.e. between ground and certain signal pins, usually caused by high voltage drop through the shell somewhere. And, well-designed equipment, fit for the car environment with all its spikes and surges, should be protected anyway. I did say well-designed equipment, much is not! For any item, leaving the ground connected and pulling out all other connections is quick, simple and foolproof. If you are using MIG, that is.

 

But you will fry your battery if you put a live torch directly on the main battery feed, or any of the brown wires. You might burn out the wiring too.

 

If you are using TIG with HF start, there may be sufficient radiated field to do damage at close quarters, so I would strongly advise removing vulnerable items from the car. But not many of you wil be using TIG (too slow for most body repairs, although ideal for making manifolds and such like, on the bench).

[monster_mini]

Cheers for all the replys, it was just a thought based on a few topics I've read on mixed thoughts about removing ecu, srs ect ect when it comes to the much later models, if it was a carb model, alternator and battery disconnected I'd not be questioning, just wanted to hear people's opinions:)

Thanks again

Nick