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View Poll Results: What should I do next? See the end of the post for full option explanations.
Fair and above board...with a paper trail.
3
21.43%
On the DL, but the guy still pays for it.
3
21.43%
Repo my own car, force him to eat the $$$ or get a lawyer.
1
7.14%
"I love the smell of napalm in the morning..."
7
50.00%
Voters: 14. You may not vote on this poll

The case of the Fried LH brain...I think the welder did it!!

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Old 02-09-2006, 05:27 PM
  #31  
Fogey1
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wds928 wrote:
"Tim, sorry to read of your LH brain situation. I really liked #4 and thought I'd offer some more considerations. A buddy (Navy) emailed me this last year.
Rules Of Engagement
US Marine Corps Rules:
... snip ...
9. Use cover or concealment as much as possible.
Those Marines, sigh ...
they forgot 9.a. Never mistake concealment for cover."


There is Option 6, pay him with plastic, take the car and dispute the charge, maybe go to small claims.

Remember that the shop has insurance for its screw-ups, maybe. So #7 might be to treat him like you know he'll do the right thing and maybe he will.
Old 02-09-2006, 08:20 PM
  #32  
Alan
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Umm interesting - all the electronics in the car are already connected to the chassis via the ground points the only thing that connects to the battery ground strap is the battery... you didn't disconnect much. In your case the battery +ve feeds the clock & alarm and the turned off ignition switch and thats about it...

The concern is only the difference in voltage you may create across portions of the cars electronics due to welding. If all the parts of the car are at the same voltage it really doesn't matter if that is 2v or 50V. What causes damage is when some parts move to a high induced voltage and others don't. Keeping both supplies to a module@ ground gives you more return paths and a lower impedance overall. But you have to connect the modules to the supplies (ignition switch) and then the supplies together.

Ed Yes - good point some of those babies are huge! Remove battery - Turn on the ignition - Count to 10 - Then connect the cars Batt+ and ground straps together...

If you prefer to disconnect the battery straps - fine your - choice of course... but I won't be doing that...

Alan
Old 02-10-2006, 12:33 AM
  #33  
TeufelHei
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A quick update (and resolution).

I went to the shop today with wire diagram, multimeter, and good will. I fixed the problem in about 26 minutes. Turns out the fuel pump fuse was blown (I told him to check it) and the relay was not fully seated. Thank goodness it wasn't any worse.

Minor points. The final result was a fully above board transaction, in which he charged me for 8 hours of labor (not 13). The manifolds are in, the down pipe was "adapted," and all is running well.

He lied about having removed the battery ground, and did not remove it while trickle charging the battery overnight. I know this because my clock was set the same (not correct) and the radio stations were still programmed. Also, the battery was connected while charging when I came to the shop.

Lessons learned. While this panned out, there were a lot of opportunities for really nasty stuff to happen. Cover your six.
Old 02-10-2006, 03:04 AM
  #34  
SharkSkin
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Glad to hear it worked out, Tim!
Old 02-10-2006, 12:06 PM
  #35  
IcemanG17
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Damm....no napalm!!!
Old 02-10-2006, 01:12 PM
  #36  
littleball_s4
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Originally Posted by Alan

The concern is only the difference in voltage you may create across portions of the cars electronics due to welding. If all the parts of the car are at the same voltage it really doesn't matter if that is 2v or 50V. What causes damage is when some parts move to a high induced voltage and others don't
No question about first part. But I would say what causes damage is feeding more than 24v to a 12v rated part, worsened if reversed in the LH or miscellaneus electronic stuff.

Originally Posted by Alan

Keeping both supplies to a module@ ground gives you more return paths and a lower impedance overall. But you have to connect the modules to the supplies (ignition switch) and then the supplies together.
I can't agree. If both terminals are "grounded" at diferent spots in the chassis then you have all the chances to get the component fried!

What happens In your "jumpered battery setup" if your battery ground strap area is at 50v and the front ground (which the LH is grounded to) point area at 0v w/ ignition on? Aren't you feeding 50v to the LH?

I understand there is a gradual voltage drop of 50v on the wide path between welding point (whenever the electrode gets stuck) and the welding machine ground jaw. Outside it's more or less 0v. if you have a wire in "parallel" to this path, you will measure some amperes trought it.

But if you always do this and you never had a problem... probably I'm wrong.

Glad to hear there are no fried LH on this case!



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