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welding woes

Posted: Mon Apr 24, 2006 7:36 pm
by swamp
G'day all
I have been fabing up a new rear bar, and have welded some plates onto
the chassis, to pick up the returns. My problem is the car wont run properly
now. I disconected the battery and alternator before welding, but I think I may have fried the electronic ignition. I know SFA about electronics could this be the problem.
Regards Michael.

Posted: Mon Apr 24, 2006 7:41 pm
by Micka
Talk to the boys at Haultech...I am sure they will know how to remedy this. Otherwise HSVRangie or ISUZUROVER will be able to help.

These sources are invaluable for Rover questions.


Micka

Posted: Mon Apr 24, 2006 10:21 pm
by uninformed
where did you place the earth??? i don't have elec anything on my car (def110) but never disconect the battery and have no probles.

always keep the earth as close to the weld as posible... elec takes the path of least resistance...

oh and i have a turbo timer and elec tralier brake controls

Posted: Mon Apr 24, 2006 10:43 pm
by mickrangie
I have welded to my 93 efi rangie heaps of times with out any problems...

how is it not running right?

Posted: Tue Apr 25, 2006 12:28 pm
by shakes
last night we spent around 6 hours welding on mine with the old electronic ignition batt d/c and no drama's?

could just be a bad coincedence... you didnt stick a hole in the petrol tank or lines or fry the pump??

Simon

Posted: Tue Apr 25, 2006 12:48 pm
by Daisy
is it possible that you didnt put the cables back on the battery tight enough? Is the battery earthed properly?

As far as i can work out... its possibly an unrelated problem to the welding you've done. Maybe go back over what you removed before welding and make sure that you've put everything back the way they were previously.
where did you place the earth??? i don't have elec anything on my car (def110) but never disconect the battery and have no probles
Good way to kill your alternator...

Posted: Tue Apr 25, 2006 7:24 pm
by uninformed
Daisy wrote:is it possible that you didnt put the cables back on the battery tight enough? Is the battery earthed properly?

As far as i can work out... its possibly an unrelated problem to the welding you've done. Maybe go back over what you removed before welding and make sure that you've put everything back the way they were previously.
where did you place the earth??? i don't have elec anything on my car (def110) but never disconect the battery and have no probles
Good way to kill your alternator...
please explain how??

cheers, Serg

Posted: Tue Apr 25, 2006 11:14 pm
by shakes
someone will be able to explain this alot better than me but....

welding (very)basics 101: when you arc weld the arc is basically electricity trying to form a circuit back to the welder. the arc heats the metal and with the flux thats on the rod helps the 2 metals react and bonds together.

This circuit essentially makes the car body "live" but will rarely give you a shock because its path of least resistance is back through the welders earth and not you.

Being that the body is "live" and having 100amps (arguments sake) pumped into it, this can quite possibly fry the coils inside your alternator being there only made to handle say a max of 65amps as with your battery can also be sucked dry to the point of exploding. :shock:

but dont hold my word as gospel.... someone please correct me if i'm wrong somewhere :?

Simon

Posted: Wed Apr 26, 2006 10:26 am
by Bush65
I have stuffed an alternator (rectifier), which I believe was caused by welding without disconnecting the battery. Welding aerial mount to top of bullbar and the earth was attached to chassis close to the bar.

I have welded in the past with the battery connected, but don't recommend it now.

Sorry no help to swamp though.

Posted: Wed Apr 26, 2006 1:43 pm
by HSV Rangie
welding on a vehicle with an Alt or modern elecs can have issues. (but not always)

Cars with alt should have the bat disconected and the welder earth attached close towhere welding will take place.


cars with ECU and alt should have a spike arrestor fitted prior to welding.

always attach welder earth as close as practical to where welding will take place and preferably on the same item being welded.

Michael.

Posted: Wed Apr 26, 2006 6:05 pm
by uninformed
always attach welder earth as close as practical to where welding will take place and preferably on the same item being welded.

Michael.[/quote]

hello we have a winner, not only will this help protect the vehicle it will make for better welding

cheers, serg

Posted: Wed Apr 26, 2006 6:09 pm
by "CANADA"
its not going to energise the whole car unless you have the earth at the opposite side...the circut will take the shortest posible route...

welding woes

Posted: Wed Apr 26, 2006 8:48 pm
by swamp
Thanks for the info.
I haven't even tried to resolve the problem but I have finnished my rear bar.
The Rangie can wait i'm of to Fraser Island on friday morning and have been getting the disco ready.
Plastic diff filler plugs on my d2 how poor is that.
Cheers Michael

Posted: Wed Apr 26, 2006 9:06 pm
by justinC
Those pesky plastic filler plugs can be replaced by the brass radiator ones.(although 1 particular disco2 wouldn't take them at all. All others have though. Must've been a friday car that one...)

JC

welding

Posted: Sun Apr 30, 2006 9:56 am
by C.A.Moseley
I'm a sheet metal worker by trade and i spend a very large part of my time welding trucks cars and busses. our forklifts also is used when holding up large jobs so it has probibly been connected to welding for some thousands of hours, we have never disconnected a batterie and never had a problem