A steering accumulator off a massive Hitachi mining truck needs to come apart for inspection, but getting these end caps undone is going to take a little more than your standard workshop tools. The accumulator has timed out and needs to be disassembled so we can inspect the internals and replace the seals. These end caps aren't something we're going to undo with the usual workshop tools, so the first job is to make a custom disassembly tool that will bolt directly onto the end cap and give us the best chance of getting it moving. We start by machining a steel plate and hex bar to make the drive plate. The hex is pressed into the plate before being welded together on the welding rotator, then it goes back into the lathe for finish machining. That brings its own challenge when we hit a hard spot around the outside diameter that starts destroying inserts. Once we get through that, the drive plate goes over to the milling machine to drill the bolt hole locations before we can test fit it onto the accumulator. With the custom tooling ready, we vent the remaining nitrogen from the accumulator, bolt the drive plate onto the end cap and bring out the torque nut runner to find out just how much of a fight these end caps are going to put up. It’s a component we’ve never shown being disassembled before, and before we can even think about rebuilding it, we’ve got to make the tooling and get this thing apart. ═══════════════ New videos every second Friday at 5pm AEST! If you enjoy the video, smash LIKE & SUBSCRIBE 👉 / @cuttingedgeengineering ❤ PATREON (early access & ad-free videos): / cuttingedgeengineering 🧢 OFFICIAL CEE MERCH: https://www.ceeshop.com.au 🛒 OUR AMAZON STORE (workshop favourites): https://www.amazon.com/shop/cuttinged... (As an Amazon Associate we earn from qualifying purchases.) FOLLOW US 🎵 TikTok: / cutting_edge_engineering 📸 Instagram: / cutting_edge_engineering 👍 Facebook: / cuttingedgeengineeringaustralia ABOUT US We're a down-to-earth, real-life machining and fabrication workshop on the Gold Coast, Australia. We specialise in helping mining and earthmoving businesses keep their machines running smoothly, and we love working on broken parts, the bigger the better! As well as our customer repair work, we also share the big workshop projects, restorations and custom shop-made tools we get stuck into, like the Franna crane project and our heavy duty parts washer build. New video every second Friday. Subscribe to follow along. #HitachiEH4000 #MiningEquipment #HydraulicRepair #Machining #CuttingEdgeEngineering