Bill's 02 Z-28 SS

Hi Folks
I have a simple question - do you or should you disconnect the battery when welding on the car???
Thanks
Bill

Louis

iTrader: (7)

I always disconnect it. One instance where I did not do so, it took out the PCM.

It takes all of 2 seconds with an 8mm wrench to do so

ta12sec

iTrader: (3)

I unhook the battery and the pcm and un plug any other accesible electronics (pull the dizzy on my blazer to) just to be safe, or snap on makes a suppresor that you hook up to the battery to protect every thing.

blacktransam

iTrader: (13)

i didn't and i did a full 6 point and true duals on the car.. I'm fairly knowledgible with electronics and the welder completes its own circuit... how could it effect battery voltage or surges??

robertbartsch

I thought - yes dissconnect for ARC (electric) welding

No for gas (oxy) welding.

I lost a PCM a few years back so I disconnect the battery every time I work on the car. I also have LS1Edit which is locked to the specific PCM in my car - a super pain if it goes bad...

Louis

iTrader: (7)

We do subframes all the time, and it only takes one fried PCM to begin unhooking the battery.

On the race car, it has a kill switch. We still unhook the PCM just to be safe.

Maybe Harlan can give some insight on this subject

robertbartsch

Didn't someone say the Helms manual suggests disconnecting the battery for welding and other work too!

Bill's 02 Z-28 SS

Hi Folks
I did disconnected my battery when I welded last weekend. the funny part is when I started the car up again, it would run correctly, it keep stalling - I was worry but after driving it for a couple miles it went back to normal operation. I would rather be safe then sorry.
Bill

HS-Y2kFormula

iTrader: (2)

That is exactly what happened to me when I had a performance shop weld my SFCs. I asked the guys if they were going to disconnect the battery, and one guy said no. He didn't think it needed to be done. I was skeptical, but didn't say anything cause this guy is pretty good with these cars. He also indicated that when you get exhaust work done on your car, it is very rare, if at all, that an exhaust shop will normally disconnect the battery when welding an exhaust system up. I thought about that and had to agree with him there. In all the years that I have had exhaust work done, not one place had bothered to disconnect the battery when welding up the exhaust.

Anyway, as it turns out, another guy in the shop actually did the work on my Formula and disconnected the battery because he wanted to be on the cautious side. I was kinda glad that he did.

However, when they pulled it out of the garage, the darn thing would not hold an idle. The guys in the shop just said that it was normal, and that the car would need to relearn its idle. At first, I didn't believe him, but by the time I got home, she was running like a champ!

1999_SS_M6

LoL.. Service manuals suggest disconnecting the battery and chocking the wheels before you add windshield washer fluid. However, in this, and a few other instances, I take the "better safe than sorry" approach. Two weather-pack connectors on the PCM, and couple spins with a the 5/16th's wrench and you're safe.

If it took 20 minutes versus 20 seconds, I might get lazy, but why fuss over something you can do in under a minute? As a caveat though, pay attention when you take your car to the muffler shop... they don't pop the hood before they start welding, if you know what I mean.

Louis

iTrader: (7)

Learned perameters of the PCM are lost when the batterey is disconnected, hence the rough running and idling