Just wondering if doing some welding on my arb bumper while its still mounted to my disco will or can screw anything up? Ie computer or electronics.

 

You want to disconnect the battery and alternator.
Make sure the ground clamp is between the Rover and the arc and that it has a good connection to bare metal.

 

Ok cool.I was thinkin that but figured Id get some other opinions.Maybe Ill just not be so lazy and take it off.Thanks Tom.

 

I would either take it off or let someone else weld so if they fry your electrics its on them.

 

Urban legend for the most part, frying the computer with a welder. I don't think in the several hundred cars I've welded on that I've once disconnected the battery or the ecu. And you'll never see an exhaust shop do this either.

The reason is if you place the ground on the piece of metal you're welding, the bumper in this case, the arc will take the shortest path back to the welder, and that's via the clamp.

Even if you went to the trouble of disconnecting the battery cable there are still a ton of other grounds on the chassis and frame that could do the same thing. ECU's have MOV filters as do most any component in your truck, and a bad alternator will fry those long before your 20V welder will.

Back working for GM I would have been dinged for losing the customers radio stations over anything else. It's about common sense, like don't place the welders ground on the ECU housing and weld to it.

You can find literally tons of information on the Miller forums about this very topic. Some people have suggested getting Mythbusters to debunk this on their show. Not sure if MB answered the letter the Miller people sent, but they were in the process of asking them to do this on some heavy machinery.

http://www.millerwelds.com/resources...nities/mboard/

 

Scott R,

Yep what you said, you mentioned the radio stations on other vehicles. On Disco's its my understanding that if you disconnect the battery (with the vehicle off), you'll have more than radio stations to reprogram - or that may be a legend also????

 

I'm with Scott R and Night Train. I welded a nut on a broken exhaust stud to remove it on another vehicle without disconnecting anything (and have since welded many other things while attached). Of course I asked the same question on a different forum first, too! What's the old saying? Ask twice, weld once...