[Reuben]

Hey guys on a round oz trip ATM and long short short we just finished the gibb river road including going up to Mitchell falls and kalumbraoo! Didn't have any problems on the road but I cleaned up the car today and notice a front diff leak turns out its a inch and a half hair line crack along the diff housing I'll let the pictures tell the story.

Just wondering is it going to be good enough too do a weld job? And if so what type on welding should I get done tig, mig,??
And if anyone knows a welder that's pretty good in or around Darwin that they could recommend? Hate the idea of the first year apprentice at some cowboy workshop stick welding in together... Haha

Thanks guys any input will help.

 

[Reuben]

Hard to see but where the oil is that's the crack.

 

[05_ENFORCER]

Give it a quick clean with some petrol and bung on some sikaflex (silastic) for a temporary repair


Dunno anyone decent in Darwin that could assist sorry. (Used to be a joint in Coconut grove, Northern diesel ???)

.

 

[steely]

You can just run a weld over that, stick MIG doesn't matter.

 

[Spud truck]

Pm sent.

 

[Leethal]

Remember to change your diff oil after it's been welded.

 

[Boundry Rider]

I know a guy from the 4WD Action forum who has an automotive workshop in Darwin, if you still need assistance I can get the location for you.

 

[Rexxo]

How'd the repair go mate? Hope the trip is going great apart from this??

 

[Reuben]

Yeh got the repair welded up by Dutchman in Darwin he's travelling round Australia with us/at the same time. He's doing a trip thread you may have seen. We gave it a red hot go but with no luck, lasted till king fisher bay from Darwin then we patched it up again their with a stick welder. But that's only then lasted till herevey bay. So time for a new diff housing...

Next questions is does any one between herevey bay and cape York a front gu diff housing their willing to sell?? Were be on Fraser for the next week and then heading to the cape for three weeks so on the way up we are hoping to make time to swap it over. Any help would be awesome otherwise I gona start checking wreckers.

Thanks guys

 

[tassie wombat]

I wouldn't worry about replacing the housing mate,take it to an engineering shop,get the old weld removed and 're welded,if the repair is done properly you won't have any problems.and please don't think I'm having a go at the person that did the repair,sometimes you just don't have the right gear or the time etc to do the job properly.

 

[Peter Mc]

Go buy some dye penetrant for identifying cracks from a welding supply shop, this will show where the crack is. My rear diff had a oil weep I found the crack with dye pen and welded it up, no issues since repair.

 

[Leethal]

If you don't replace it Reuben you'd want to do a bloody good job repairing it as crack will spread very easily. Mine was welded by the old fella at Lorrella Springs with a stick welder, two days in a row, wouldn't let me have a go. Then half way along the Gibb...

So in Derby had to grind out all the weld, cut a V into it, welded it with a high amp stick then migged a slab of 8mm plate over it. Worked a treat but all that heat would have bent it so now I have replaced the housing...

Look at the one Ben and Clare came across on the Gibb... That's what will happen if it's not done properly, and you won't get much warning, if any.

 

[RD&D]

Like others have said needs to be done right, oil drained, grind it out get all the oil residue off the area to be welded and unless you are a gun with a arc welder I'd use a mig.

 

[Sharky1]

Yep, you need to know more about welding for this. The problem you have is that yours cracked right on an existing weld. You can't successfully weld over that unless you know the exact parameters of the original weld, no matter what metal it's made from, although steel is more forgiving. Also what you're welding there is a sealed compartment. That classes it as a pressure weld. That is a very exclusive field of welding. It takes a long time to get your qualifications for pressure vessel welding. If the diff housing was totally empty your chances of a successful weld would greatly increase.

You definitely need to get all the oil out & clean BOTH sides of the crack thoroughly. In my opinion, I'd be getting a new housing because if you're going to go to all the trouble of doing all this, you may as well put your bits back into a good housing you can trust. Then you can weld yours & sell it or keep it as a spare.

And don't forget, when welding anything on a car, ALWAYS disconnect BOTH battery terminals.

 

[q8160]

Cracks like you have are not uncommon and not conducive to any particular vehicle make.

Biggest mistake so often made is that the ends of the crack are not stop drilled and the crack is not ground out before welding. In other words, just welding over a crack, even though it may look the 'ducks guts' is headed for failure.
As for a diff housing to be considered a sealed unit (pressure vessel) requiring specialist welder qualifications is horse shlt..... all diff housings are vented.

Have seen housings welded with a good invertor stick welder along with good prep carried out, result - excellent and only one vertical down applied....... and as far as I know is still in service many years later (done on a cape trip).

Been on the Gibb a couple of times.....certainly is not a 'black top' ..... could say a bit rough.

Just looking at the weld repair, plus you have travelled from NT to Frazer Island, I don't think you will have any problem with the crack re appearing, however saying that and the size of the weld, I would be more worried of a crack appearing somewhere else due the distortion and stress from the welding process as applied. If the man who doing the welding took the stress due weld shrinkage and heat into consideration then all should be fine.
Basically...
A good TIG would be my preference... drain diff... heat crack area to 'dry' the oil off the inside....stop drill and grind the crack out... fit drain bung... fill housing through breather with argon... weld... result should be perfect penetration etc..

My 2 bobs worth

 

[shanfab]

Cracks like you have are not uncommon and not conducive to any particular vehicle make.

Biggest mistake so often made is that the ends of the crack are not stop drilled and the crack is not ground out before welding. In other words, just welding over a crack, even though it may look the 'ducks guts' is headed for failure.
As for a diff housing to be considered a sealed unit (pressure vessel) requiring specialist welder qualifications is horse shlt..... all diff housings are vented.

Have seen housings welded with a good invertor stick welder along with good prep carried out, result - excellent and only one vertical down applied....... and as far as I know is still in service many years later (done on a cape trip).

Been on the Gibb a couple of times.....certainly is not a 'black top' ..... could say a bit rough.

Just looking at the weld repair, plus you have travelled from NT to Frazer Island, I don't think you will have any problem with the crack re appearing, however saying that and the size of the weld, I would be more worried of a crack appearing somewhere else due the distortion and stress from the welding process as applied. If the man who doing the welding took the stress due weld shrinkage and heat into consideration then all should be fine.
Basically...
A good TIG would be my preference... drain diff... heat crack area to 'dry' the oil off the inside....stop drill and grind the crack out... fit drain bung... fill housing through breather with argon... weld... result should be perfect penetration etc..

My 2 bobs worth

Great advice right here .

when Mine cracked in the exact same spot I Did pretty much what q8160 detailed .
I drilled the ends of the crack , fully ground out and beveled . and blasted it with the tig .
I didn't purge the diff though as I'm a fairly competent Tig welder and at the time was doing alot of spool work at the time ( HP Pipe welding ) . when I ground it out I just cut right through the diff to ensure correct penetration . I had that Shorty for another 6 years after the repair and it copped a hiding and it didn't crack again .

 

[Dutchman89]

Hey guys im the guy doing the welding.
Both times its been repaired properly. We drained the diff oil and wire wheeled all the paint off to see exactly where the crack was. We then put a 1mm cutting disk through the crack to the other side and extended it about 10mm either side of the crack lengthways.

Unfortunatly the first time the mig we had couldnt be turned down so i had no other option but to do a vertical down.

The second time we did the exact same thing except i had access to a stick welder which i prefer as i have done plenty of site/ structual welding in my time. I took some 16tc 2.5s with me on our trip and used them to weld it up. I wasnt able to heat them up before i used them as we didnt have access to an oven.
I agree that a tig would be the best option, but by the time it would take someone to prep it and weld it, the cost would be close to the the cost of a second hand diff housing.

In normal circumstances im sure the repairs would last years but the combination of all the extra weight and the 1000s of kms of rough corrigations just puts a massive amount of pressure on everything. I personally reckon that a replacment diff housing is the only option. There is only a certain amount of repairs that can be done before you need to count your losses.
If we were to send it to a normal workshop to get repaired i would say that they would do the repair the exact same way i did. And the roads that we have been taking and the roads we are yet to take are the type of roads you need complete trust in your car.

Also im a qualified boilermaker - just for the record
Ben

 

[Reuben]

Hey guys back in the south if faser again. Thanks for everyone replies you all know more then me so im gratefull. As duchman said we gave it a fairly good go from the start. At thr end of the day cost vs garrenty of a perment fix is what im most worried about. Not having worked for 4 months and all. If the cost of a good welder with a tig is well below the cost of a second hand diff housing then thats the go. But im guessing no warrenty will be offered by the shop which worries me after seeing the leak appear twice after i hope it was sorted. So the other option is finding a desent diff and swapping it over myself keeping the king pin bearing assembly i think??? still together on the "new" diff. Which would keep the job simpler. This all depends on finding one for the write price. Could anyone let me know a rough price i could be looking at? Really appreciate the advice so far.

 

[madk1w1]

Also im a qualified Platebasher - just for the record
Ben

Corrected


Enjoying the read and getting that little bit greener by the day:bigthumb: