In Reply to: Cracked 9N Axle Housing, cast iron or cast steel? posted by JP on April 12, 2019 at 11:52:53:
The N-tractor housings might as well be mild steel as far as any welded repairs have worked for me. The welding rods I have specifically for cast iron are type ESt. That is an all-position rod and the finished welds do rust, so the repair is not as noticeable as other methods. I've also used regular E6011 rods on some N-Tractor cast parts with good results. Even though I buy all-position rods, I don't weld anything upside down if there is any way to avoid it.
Anything broken is no loss to try and fix. Worst case you waste some time and make it look ugly before tossing it in the scrap pile. The main issue I see with welding or replacing the axle housing would be why it broke in the first place. Is repair or replacement going to prevent the same breakage? The original structural problem needs to be addressed either by making the repair much stronger, altering the mounting method, or removing forever the accessory that caused the problem. Maybe it broke because something shifted when that housing was cast making that area thinner than usual. Not all casting defects were caught or considered bad enough to toss the part.
A cast iron transmission I repaired in 1981 is still around. Not sure why, but I still have a 1965 Chevy cast iron 3-speed manual transmission. One mounting ear was snapped completely off, so I got it free from the junk yard, welded the ear back on, and used it in several vehicles.