hey guys
i have a cracked GSR transmission case that i am trying to repair but it is giving me a hell of a time.

using my lincoln tig 185 running a green tungsten set on AC and argon at 20 with 120 amps. when i get the arc going it is just going kind of nuts and it raises hell with the tungsten. it blows a hollow hole in the end of the tungsten, if you can picture that. and i have clean the case up.

my buddy was just reading through one of his textbooks and it said something about trying DC- so maybe i can try that tomorrow but everything else i have always done i ran AC.


so any help would be appreciated. if any of you have welded on these cases and could share some pointers that would be great. thanks for your time

 

You should be able to do it on AC. I welded some 6061 peices to the case and it welded kinda shitty but it's holding just fine. I tried straight polarity as well but that was even worse (maybe better with helium?). The castings composition just isn't that great for welding I guess. If you don't mind, I'd be interested to see yours and other peoples repairs on tranny casings. I did a few, and I'll throw pics of some of my welds on this **** as well if you don't mind.


Modified by preludeserge at 4:07 AM 6/22/2006

 

yah i can post up pictures. i cant even get a nice puddle going to feed filler into as of right now. so not much to look at

 

Step one: verify shield gas flow. (learned that the hard way a couple times. )

Could be contamination; try cleaning as best you can and then preheat the area with propane/MAPP/acetylene/what have you to boil out the gunky stuff.

Make sure you've got a good ground reasonably close to your work area too. Depending on what part of the case you're repairing, you'll likely need more than 120A, although a little preheat goes a long way.

 

Try taking a piece of clean billet aluminum not a cast piece and see if it welds OK. AC is where the machine should be set at and as long as you don't have any drafts 20 cuft should be enough also. Make sure you have a clean cup ( one that hasn't been used on steel)
Castings can be very tricky to weld and some you need to be exceptionally careful with the amount of heat and how fast you put the heat into it. You need to be very patient and bring the case up to temp slowly. this will also try to help burn some contaminants out of the material. Once you get a small puddle feed a small amount of filler wire and let it mix with the cast material and you will usually have an easier time after that. A very important thing to do is to peen the welded area. Use a rounded over punch or a small ball peen hammer and tap the entire surface . this will help to keep things from cracking by eliminating the suface tension and also work harden the filler making it a little stronger in the proccess

 

thanks for the input guys. i wasnt preheating the case.
i am doing this in the car actually. where one of the rear tranny bolts goes in the case through the rear mount is where it cracked. so i am trying to fix it without taking all the **** out. i also didnt have a clean cup that i hadnt welded steel with so that may be causing some trouble as well.
again thanks for the tips and if anyone else has done something like this feel free to chime in.

 

Doug over at DG motors says he won't lay a bead on cast aluminum unless he preheats it in an oven or something. That's what he told me when I asked him about repairing one of my spare blocks that had the left mount broken off.

 

You will def. have troubles welding a cold peice of cast alum. not unless you have a aerowave 500 or somethin...lol.....besides it will have to be super clean

 

It doesn't matter what welding machine you have .It still won't weld for ****. Its Die cast and die cast is not made to be welded on.It is made to be light and strong. Thats why it has the bubbles in it. You can weld it but don't get it real hot or it gets worse. And what you want to do is get some rod to stick . as soon as you get a good bead of clean rod. Then it will weld OK.Just shove the rod in untill you get it to cover. Then make it look good after.Also if its oil saturated it makes it harder.take some Eagle one etching wheel cleaner and clean it real good. and rinse it clean with water.

 

I really really really despise that ****. This is the super pimp 50 dollar grind free LS transmission for my sisters DA tegger. I assure it won't weld very pretty at all. I think I did this one with 4043 but I've had better succes on other projects with 5356. I did this with a 180sd.
Before

After

 

i have welded a few cracked trannys in the past for a local tuner shop. i had no problems welding cracks. i took a cut off wheel and slit the crack to make a larger valley then used weld clean to prep it folloed by a water bath and it worked out fine. shouldnt be a big deal just to weld a crack. its hard to do in the car though im sure.

 

is the crack leaking oil or is it just a boss for a bolt that has split. If you have a crack with oil involed your wasting your time . even if you drain the trans you will
have residual oil finding its way into the crack. You really need to know what your doing to try and pull that off.