Welding a small hole in a NP242 Transfer case

[kfrosty]

To me it looks like Aluminum but would like to verify.

The hole is not bad and it's in a corner as you can see in the picture. I was going to pull it but have it up on my lift and now contemplating on trying to weld it without pulling it out. (I've purchased a replacement in case I can't get it fixed.)

I'm not a great welder, I've got a Miller 250 welder with an aluminum gun and just got a Lincoln Tig Welder I've been tinkering with.

The hole is on the bottom directly overhead, looking for ideas of how to best go about tackling this.

If aluminum, I would assume just start around the edge and come in a little at a time to start closing the gap?

(I'm going to try the vinegar trick.)

If this is by chance Magnesium, I suppose I'm to have to tig. Would you attempt to do the same with a stick?

Thanks



Update: I got some White Distilled Vinegar and splashed it on the case and do not see a reaction so I'm going to assume this is aluminum but would appreciate if anybody could confirm. So with that, question comes to do I use the aluminum spool gun or try to Tig. I've never used the aluminum spool gun. Dabbled with Tig but haven't figured it out that good yet and never anything overhead.

 

[TrailLifeBill]

I'm no welder, but this reminded of an issue I had about 5 yrs ago with a pressed in heater hose nipple that developed a pinhole leak at the intake manifold of my truck. Ford's fix is to replace the whole manifold (vehicle had 115,000 miles on it with no other issues). As a "hail mary" attempt at a cheaper fix, I got some JB Weld, mixed it up and dabbed it onto the nipple. It's given no more problems and now has 225,000 miles. If I were to have a similar problem as yours and were on a roadtrip with no welding equipment available, I would definitely give that a try. Since you obviously have the equipment and know-how, I'm following this thread to see what a proper fix looks like.

 

[gimpyrobb]

Yup, try the JBweld first. If you weld that hole, your going to have to do it like 12 times from all the contamination you'll get.

 

[doghead]

You'd need to pull it to weld it, the oil will contaminate your weld.

Epoxy putty if you want to try without pulling it.

 

[kfrosty]

The oil drain plug is lower than this hole. So I can get the oil out, scuff and degrease it.

JB Weld was something else I thought up but not sure how much I should trust it. Plus I bought these welders for situations just like these.

The JB Weld, would you trust it as a permenant solution? This truck I drive here and there but more important off road in it. I don't want something I'm going to have to fix again later.

Thanks

 

[gimpyrobb]

I have no size reference to be sure, but it looks like a green pea size. Even if you could get in the case and scrub it down with actone and a stainless wire brush, the metal is porous and you'd have to do the weld a few times. I have an AL oilpan on my VW that cracked, it got fixed with a rivet and epoxy. Its been like that for 4 years now. I'd say I trust it.

 

[kfrosty]

I have no size reference to be sure, but it looks like a green pea size. Even if you could get in the case and scrub it down with actone and a stainless wire brush, the metal is porous and you'd have to do the weld a few times. I have an AL oilpan on my VW that cracked, it got fixed with a rivet and epoxy. Its been like that for 4 years now. I'd say I trust it.

Yes, you are correct on the size. Probably about a pea size, it just likes kind of big because i got the camera up close to get a clear picture. You could stick a pick up gum in it to fill it up.

Epoxy would be the easier route, but thought I'd figure out how to use my welders on something like this.

I found this and thought it could be something as simple as this.

https://www.youtube.com/watch?v=3NRJC7u37gI

Reading the comments he actually used JB Weld on top of it "Just in case"

Thanks

 

[kfrosty]

P.S. If nothing else, can anybody verify the NP 242 is aluminum?

 

[snowtrac nome]

here's my experience for what its worth. Cast aluminum or magnesium can be tricky to weld when it has had in it, impurity's are the death of it. I have seen vw cases successfully welded which are magnesium, the heat really warped things bad weather you are doing aluminum or magnesium its important to use the right alloy. I think if the hole isn't structural I would use a good epoxy like belzanna or jb weld. your choice at the end of the day.

 

[kfrosty]

JB Weld it is then. I'll drill some holes in Aluminum and practice on that.

Thanks for the input. I'm just happy it's not as bad as I thought it was going to be. Something broke in the dark, we pulled it out think it was a half shaft. Turned out to be the Front shaft. While pulling it up the hill, the the shaft wrapped around some lines and poked the hole in the transfer case.

So the moral of the story, if you lose front drive, do not move it till you get up under it and look. If I would have had a light or waited till the next day and got up under and looked, all I would have had to do is slide the drive shaft out and fixed it.

But now I get to fix transfer case as well the drive shaft and replace the lines coming out of the transfer case.

Thanks for all the help

 

[doghead]

Learning to weld aluminum is great.

Learning on a dirty transmission, inverted is not the way to learn.

Even if you had it out and cleaned it the best you could inside and out, it is still going to be tough to weld due to oil impregnation in the case.

 

[73m819]

Even if JBing, you need to get the oil oil out of the metal at the to be fixed spot, I would use some heat to bring the oil to the surface, then acetone, keep doing this till the area is clean, does not have warping heat. JB weld will not adhere to a oily service, even cleaning with acetone alone will not get the oil out of the metal, JBing will last a bit but will tend to crack at the connection edge due to the heat of the operating tcase bringing out the oil in the metal, so if you plan this fix to be a permanent fix rather then a temp, take the time to clean the metal likes it needs to be.

 

[kfrosty]

Even if JBing, you need to get the oil oil out of the metal at the to be fixed spot, I would use some heat to bring the oil to the surface, then acetone, keep doing this till the area is clean, does not have warping heat. JB weld will not adhere to a oily service, even cleaning with acetone alone will not get the oil out of the metal, JBing will last a bit but will tend to crack at the connection edge due to the heat of the operating tcase bringing out the oil in the metal, so if you plan this fix to be a permanent fix rather then a temp, take the time to clean the metal likes it needs to be.

So basically welding or JB weld you have to do the same? I'm going to pull the drain plug and let it drain, I've got a small soldering torch I'll spot heat and go from there.

 

[Jbulach]

The first rule of "good" welding, no matter the method or material is clean the material the very best you can. As stated make sure to use a designated stainless brush for cleaning aluminum. Try your very best not to contaminate this brush with anything including steel or oil.

 

[73m819]

As far as heating goes, do NOT just heat a small area right at the hole, warm up a area about 6" around the hole, this will keep the area clean so you can get a good adhesion other wise if ONLY heated right at the hole the contamination will migrate right back to the just cleaned area. ALSO HOT is NOT wanted, if you can not put your hand on the heated area, IT IS TO HOT, TO MUCH HEAT WILL CRACK THE CASE, let it COOL down between heats, besides keeping the heat down this will help getting the contamination out. Once the JB adheres to the porous aluminum, it is not coming apart, this is WHY cleaning is so important.

 

[patracy]

I have no size reference to be sure, but it looks like a green pea size. Even if you could get in the case and scrub it down with actone and a stainless wire brush, the metal is porous and you'd have to do the weld a few times. I have an AL oilpan on my VW that cracked, it got fixed with a rivet and epoxy. Its been like that for 4 years now. I'd say I trust it.

I'm for Gimps idea. As well as others. Clean it with parts cleaner or acetone, heat it to draw more oil out of the metal, then clean again. Then I'd put a dab of JB weld around that hole, then put a blind rivet into it. That way the rivet gives the JB weld support. Or I'd give a try at MIG welding it in spray transfer.

 

[98G]

Don't use brake cleaner for any of the cleaning...

 

[patracy]

I should have clarified, only for the jb weld. Acetone only for welding.

 

[pigpen60]

I know I'm late to the party but I have never had AL crack after welding. If there is a bushing close to the welded area its possible for it to get too hot and ruin the bushing. Had that happen on a cracked output housing on a jeep TC. When you weld it first clean with Acetone then like you said weld it around the edges cutting back on the heat as you go. You will have crap in your weld so let it cool and with a die grinder grind out the crap and go back and reweld till its sealed and clean. On the die grinder remember to use a burr/cutter that is new or only used on aluminum or you can contaminate your weld. Now on another side they make aluminum solder and I have seen this used with good results but like we told folks at the radiator shop "solder flows like water" so position is critical. And I use TIG for most if not all of my repairs on AL.

 

[Terrh]

I'm late to the party too!

Lots of conversation about aluminum welding on here. Can't say I know much about it, yet. But I do know a fair amount about the NP242XHD, I had to rebuild the one in my GMC pickup after the "pump rub" issue killed it and wore a hole in the case like yours.


Anyways, The NP242XHD is Magnesium. Trying to weld it will set it on fire.

I managed to set mine on fire trying to get a stuck bearing out of it. Luckily managed to put it out before the fire spread but only just. JB weld has been holding up on mine for several years now with no issues.