Welding Cast Iron Transmission

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A hobby farmer broke a chunk of casting out of the transmission housing on his tractor. Its a part where the 3 point lift/hitch assembly goes on the bottom/back. I'm thinking to repair the hole to create a no-leak situation. Then fab up some new mechanically mounted re-inforcing plates to spread the "Stress". I got time to start repairing. I put a piece of steel inside the hole, then Migged it in to stop the oil leak. Didn't appear to crack as it cooled, maybe cause I used short beads? Worst casting I've ever seen! Large porous, granules, not like fine grained casting, I'm used to seeing. A pipewelder guy at work is going to give me some Cast Iron repair rod that he used at a boiler plant before. He thinks it may minimize shrinkage while cooling. There is going to be a big hole that will need to be filled as a smaller chunk pulled out of the original broken piece. This spot is going to cause trouble. I'll grind it back to bevel the edges around that. I have photo's that I will post as time allows.I ground the patch clearances last night then used the bolts and the mounting face for alignment. I put a jack under the piece to hold it up. Screwed in the bolts with the jack snug then checked the wiggle of the bolts. Removed the piece, ground some more clearance. Re-installed, tightened jack up a little more. Bolts were very snug. (I'll thread chase the holes in the end). I have a sample of Forney's "Noma-Cast" (non-machine-able repair rod). End of piece is an inch & quarter. Pre-heated, welded one bead on one end, peened, welded one bead on the other end same amount. I'm thinking that when I get around to the machined face and the final passes, I'll switch to "Chronatron 211" which is a machinable Nickel based rod. It’s advertised as being "God's Gift to ALL Cast Iron Welding Men!" This way if it spills into the bolt holes I'll be able to still chase the threads. I used the Noma-Cast on all the root welds, trying to put the Chronatron on to shape. It just didn't perform as expected instead tending to sag/droop from being applied overhead.I adjusted the brake on the repaired side and put the wheel back on and filled the transmission with gear oil, then started the engine and drove it out of the shop. I took it out for a little test drive to move the oil all around in the transmission. While parked it I investigated the previous repair on the other side. It didn't take much to break through the repair on the other side. Apparently it was a "Cosmetic" repair verses a real repair! I pried the piece out without much effort. Now is the time to repair the other side for a REAL repair!I’ll post some pictures of the second side soon.
Reply:If you can find messer mg289 rod it will be your easiest solution. That rod is the best I come around so far. I always pre heat and post heat all my cast iron projects.
Reply:Is that a good out of position rod? Welding steel up side down is hard enough, cast iron seemed next to impossible! Here are the photo's of the Right Side Repair, the Left Side is mostly what I wrote about, but still its the challenge and skill..drujinin Attached Images
Reply:Your gonna want to give it a slightly bigger bevel. Yes mg289 is a out of position rod  MG 289• High strength alloy for dirty cast iron. • Machinable deposits. • Specially designed for contaminated, oil soaked cast iron. • Alloyed core wire with unique flux coating produces strong, crack-resistant welds. • For uses such as: joining cast iron to steel, transmission gear housings, gray, ductile, nodular cast iron, and sewer pipes.That's for there wire but you can also buy it in stick and tig rods. They make thee best cast iron stuff by far!
Reply:Slightly bigger bevels?LOL!If and when it ever breaks again, I'll remember you told me I should have.Thanks!
Reply:What kind of tractor? Judging by the color and what little else I can see I'm going to say David Brown.HH 187Miller Bluestar1EAHP AlphaTig 200X
Reply:It is a Vladimir T25 (Belarus) built/imported around 1987. It is interesting because it has a hydraulic brake cylinder for the "trailer" brakes and a counter balanced 2 cylinder air cooled Diesel engine!