Front axle hairline crack

[Desert Bred]

It likely a crack that resulted from around a porous casting. I've seen this multiple times before in some of the lower quality Chinese tractors back in the 80's and 90's... They would also grind the castings to smooth out outward defects. Fei Dong made a decent tractor, better than many of them...But anything is possible. You'll likely need an axle housing before it's over if you have a front end loader on it. I have a dealer friend that specializes on Chinese parts and has a warehouse full of them. He's in FL but sells all over the US. IF you need a housing or parts pm me and I'll give you his contact info.

I heard about brazing haven't looked into it though yet .
It does appear you're right about that porous casting I looked at it closer and it bulges a bit and then appears grinded down before paint (someone else above also noted that) - the loads are a bit on the heavy side due to this Davis 8d14 loader from the 50's I have on it and it was made like a tank with a 5 ft bucket. Very heavy piece here . Frame alone weighs more than the previous frame and loader/arms I had on it (MF 216 with 4ft bucket). Front wheels kept clipping the mounting frame so i needed to change it.

Going to try to keep those loads down some and look into some prices on another axle. Thanks for those responses full of insight and I'll be pm'ing you about that friend of yours. Thanks
Db

 

[muddstopper]

I always use a nickle99 stick rod for welding cast. If you drain the oil from housing and then heat the crack with a torch, you will burn out the oils from the pores. Keep the torch handy. You want to preheat when you weld it, and you want to post heat it when your done.

 

[Mark @ Everlast]

I've seen this many times as I said....welding it won't fix the porosity at the site. The part in the middle is likely a ingot of slag that was trapped during the casting process and it's cracked around it...the "QC" people at the factory caught it, but unfortunately instead of rejecting it, it was ground down...and puttied over.

 

[muddstopper]

Mark, you may be right, but if the alternative is to try to weld or replace the axle, I would at least give welding a shot before buying a new axle. A hand full of rods, a little grinding and patience might do the trick.

 

[ishiboo]

I've seen this many times as I said....welding it won't fix the porosity at the site. The part in the middle is likely a ingot of slag that was trapped during the casting process and it's cracked around it...the "QC" people at the factory caught it, but unfortunately instead of rejecting it, it was ground down...and puttied over.

What you are saying might be true, but it's usually worth spending the $50 or whatever to have it welded up and seeing what happens versus trying to find a likely expensive and hard to find part immediately. That crack does not currently look "that bad" and the majority of the stress from the loader work would be on the bottom "web" (yes, it's a tube) of the axle. So with even a semi-decent weld it should hold up fine, the biggest components are keeping it from spreading if it is a crack/void, and preventing the lube from leaking out.

I am not familiar with cast iron welding but have seen things fixed, as well as the references here… it seems highly likely this can be fixed without spending big bucks on a new axle.

 

[Mark @ Everlast]

What you are saying might be true, but it's usually worth spending the $50 or whatever to have it welded up and seeing what happens versus trying to find a likely expensive and hard to find part immediately. That crack does not currently look "that bad" and the majority of the stress from the loader work would be on the bottom "web" (yes, it's a tube) of the axle. So with even a semi-decent weld it should hold up fine, the biggest components are keeping it from spreading if it is a crack/void, and preventing the lube from leaking out.

I am not familiar with cast iron welding but have seen things fixed, as well as the references here… it seems highly likely this can be fixed without spending big bucks on a new axle.

$50.00??
This is specialized welding. You can't even buy a box of electrodes to do this task for that. You have to preheat and post heat this metal. You have to grind the affected area out...then build it back in. Seeing how I've worked on these type tractors and seen this before, all the way back to 1986, the axle housing will make a good door stop nothing more. You have to disassemble the axle because there are seals and bearings in the vecinity of this area. You are looking at 300 or 400 dollars for this repair. An end axle housing like this is not that expensive.

 

[muddstopper]

Hobart Nickel 99 Stick Electrodes — 3/32in. Dia., 10-Ct., Model# H500531-RDP | Welding Sticks Wire| Northern Tool + Equipment
Little less than $50 I figure. Yes it has to be disassembled, but it also has to be disassembled and reassembled if he chooses to buy a new axle.
Preheat and postheat isnt that big an issue either. Last casted metal i welded i used a propane weed burner and heated the entire assembly to 800F, Kept it at that heat while i welded it and didnt have any cracking problems. I am not a profession welder by any stretch, but I believe I would try welding the piece before springing for a new axle housing.

 

[Arc weld]

Brazing would be a better option but it would have to be completely disassembled and lots and lots of preheat. I think it would be good to determine if it's a stress crack or just a casting flaw that is leaking. If it appears to be a casting flaw, then maybe cleaning it really good with a carbide burr on a die grinder, heating it just enough to burn any oil out and using an epoxy would work fine for stopping the leak. If you tried this, it would be best to take the axle off and set it so the flaw is facing up. Then the epoxy wouldn't run. Cleaning it up would best be done overhead so the filings fall away from it. You just want to keep any filings from getting inside.

 

[Shield Arc]

You could always do the old trick before selling a car, that the rear end was going out. Pack it full of saw dust, or banana peels. :laughing:

 

[pmsmechanic]

I am not a professional welder by any means though I have done a lot of welding for the neighbours and I like to build my own stuff. I also like to experiment and have found Actec 223 rods to work very well for welding cast and forged iron. They're a bit of a sticky rod but once you get them going they weld ok. My thoughts are that if this is just a casting flaw then brazing would be good enough. If stress is causing this crack then I'd be either looking for a different axle or if your going to all the work of taking this axle out to weld it then while it's out you might want to design and weld in some reinforcement so that your heavy loads won't cause the same thing all over again. I'll be interested in seeing what you end up doing.

 

[yomax4]

In any event, You will need to stop the crack. If you just weld it, It will likely keep moving under pressure from using it. There is an old Welco product called Krack Sealer. Looks like a big black crayon. It was designed to seal poor cast iron welds. You heat up the part and rub it in and it will plug the leak. The problem of the crack expanding will still be there. Most cast cracks will require you to drill a small hole at each end of the crack to stop it's progression. Stick welding will suck so much oil out of the cast you will likely have to weld/grind/weld/grind until you get a good looking repair. I like spray powder cast repairs but you would have a nice fire going with all the oil..Try a high quality stop leak like Lucas.. If it doesn't work or if it gets worse, Have it done right..

 

[ishiboo]

$50.00??
This is specialized welding. You can't even buy a box of electrodes to do this task for that. You have to preheat and post heat this metal. You have to grind the affected area out...then build it back in. Seeing how I've worked on these type tractors and seen this before, all the way back to 1986, the axle housing will make a good door stop nothing more. You have to disassemble the axle because there are seals and bearings in the vecinity of this area. You are looking at 300 or 400 dollars for this repair. An end axle housing like this is not that expensive.

I was assuming he would remove it and take it to someone with cast experience ready to go. I can't imagine charging $300-400 for doing an inch weld but I could be wrong, never hired someone to do cast before. What's the price of a new axle housing?

The Kubota's I own and have seen would have been perfect, you just unbolt the planetary/etc off the end of the axle with 4 bolts, pull out the axle shaft (no retainers) and you're left with a big cast only area to weld on. The seals/etc. on the other side handle the pre/post-heat.

 

[Mark @ Everlast]

Mudstopper, that was for 10 pieces of 3/32. That crack is probably 2 inches long. For any strength and permanence you 'll have to ground it down, cut out the slag between the two cracks, preheat, postheat, and lay bead ontop of bead to fill the gap back in.

It's more than 1" in my estimation, knowing the rough scale. But maybe the OP can put a tape on it for scale. It looks like the crack is spidering off on the left side up and to the left. Cast iron repair takes special skills...You don't go to your family doctor for a heart by pass, and a cardiologist definitely charges more for his expertise. Chinese seals don't hold up to temps very well, not the ones that are in this unit. The whole assembly needs to be heated if possible for best results.

 

[Arc weld]

If it was cast steel, it's unlikely it would have a casting flaw. If it is a casting flaw on cast iron, which it most likely is, it would be almost impossible to do a repair with stick welding without cleaning all the bad section out. A carbide burr would be best as a grinding wheel messes with the carbon in cast iron. Trying to do a quick fix on bad cast isn't going to work. Can it be repaired? Probably by someone with experience but it's certainly going to cost more than $50. If the whole axle has to be taken apart because a lot of heat is needed, I can see it costing several hundred dollars. Clean it up really well with a wire brush on a grinder and then carefully inspect it.

 

[muddstopper]

I went back and looked at the pics again, thought about the process of how I could fix this at the lowest cost to me if it was mine. This is the process I came up with, if it was mine.

First I think the crack is most likely a casting flaw, sand pocket or some such, and not a failed structual defect. Cant really tell by looking at the picture. With that in mind, i would remove and disassemble the axle. Pressure wash to get rid of any excess oil and grease. Then I would take my air grinder and a good burr bit and start grinding out all the bad metal, until I got out of all the grit and gobble guke that would prevent a good weld. From the look of the defect, it appears to be about 1in wide so i would probably endup with a pretty good hole. I would then take my weed burner and start preheating the metal, all of it , not just around the hole. this should get rid of most of the oils that have soaked into the metal. Once properly preheated,(meaning around at least 600deg, but closer to 800 deg.) I would Surprise! Fire up the mig and start filling the hole. I would use 100%argon gas, your already going to have some carbon in your weld from the burnt oils. Make a pass, check heat, ping with hammer, make another pass, ping with hammer, check heat and repeat until the hole is completely filled. Always maintaining a temp of 600-800 degrees by using the weed burner. Once the weld is complete, cover in a heavy layer of sand and let cool. Check for cracks grind smooth, paint and reassemble. This may not be the way some of the professional folks would do it, but I'm just a hack.

Another thing to consider, since i dont think this crack is structual and more a casting flaw, My only real concern is to just stop the oil leak, If that is the real goal, one could just clean it up and apply JBWeld. If once i got the thing disassembled and i found the crack was more structual and not just a casting flaw, I would probably still weld , but would use one of the ziplock cast welding systems which would run up the welding cost of the repair a significate amount. Before going that route, i would start comparing the cost difference between the welding and replacement.

 

[SPYDERLK]

When you get to the metal and can see the metal fault; If its a casting flaw --- porosity covered by filler, and NOT actually a crack, you can stop the seep by solvent cleaning, drying and applying Loctite wicking compound. It will impregnate the porosity and cure. Total cleanliness for application isnt necessary.
larry,

 

[crazyal]

As an ex level 3 NDT technician my advice would be to talk to a certified inspector. There are a couple of tests that can be done without taking it apart to check for cracks and better tests that can be done if you disassemble the axle. Right now you have no idea if there is porosity and if so how much there is. It's also possible that you now have a crack. Do you want to waste time and money trying to blindly fix the axle only to have it break a second time?

 

[Desert Bred]

When you get to the metal and can see the metal fault; If its a casting flaw --- porosity covered by filler, and NOT actually a crack, you can stop the seep by solvent cleaning, drying and applying Loctite wicking compound. It will impregnate the porosity and cure. Total cleanliness for application isnt necessary. larry,

The last fee days I've moved a bunch of dirt and i haven't checked on it but had a front wheel almost come off and a back tire gone bad but nothing vis a vis the front axle. Thanks for the responses I will have to sit down this weekend and re-read them/again and I wanted to write because I appreciate the help guys. DB