nc_beagle Posted June 13 Report Share Posted June 13 I got curious what instructions ChatGPT would give me for rebuilding a G54B with a blown head gasket. I'm not experienced enough to know what it may have missed but it was pretty impressive how it laid out the steps (though I assume they would apply to most any engine.) It's answer is below -------------- Rebuilding a Mitsubishi G54B engine (2.6L inline-4, part of the Astron family) with a blown head gasket involves careful disassembly, inspection, machining, and reassembly. Here's a comprehensive step-by-step guide: 🔧 Tools & Equipment You'll Need: Socket and wrench set (metric) Torque wrench Engine hoist or crane (optional but ideal for full removal) Engine stand Gasket scraper and razor blades Plastigauge (for bearing clearance) Micrometer and dial bore gauge (for measuring tolerances) Service manual (for torque specs and procedures) Cleaning tools (solvent, rags, wire brush) Sealant (for specific gaskets if needed) Replacement parts (see list below) 🧰 Parts You'll Likely Need: Full engine gasket set (includes head gasket) New head bolts (recommended — often TTY) Piston rings Main and rod bearings Timing chain or belt (depending on year/version) Oil pump (inspect and replace if worn) Thermostat, hoses, and belts (replace if aged) Fluids: oil, coolant, assembly lube 🔩 Step-by-Step Engine Rebuild Process 1. Engine Removal (if rebuilding fully) Disconnect battery. Drain all fluids — oil and coolant. Label and disconnect all hoses, wiring, and sensors. Remove intake and exhaust manifolds. Detach engine from transmission. Remove engine mounts and lift engine using hoist. Mount engine on a stand. 2. Cylinder Head Removal Remove valve cover. Loosen head bolts in reverse sequence (to prevent warping). Remove cylinder head — inspect for warping or cracks. Inspect valves, valve seats, and guides. Check camshaft wear (if overhead cam). 3. Disassembly of Bottom End Remove oil pan. Unbolt connecting rod caps and remove pistons. Remove timing components. Unbolt and remove crankshaft. Remove old bearings. Clean all parts thoroughly. 4. Inspection and Machining Cylinder Head: Check for flatness (max ~0.002" warpage). Resurface if needed. Check valve guides/seals and do a valve job if needed. Block: Inspect cylinder walls for scoring. Measure bore size and taper. Hone or bore cylinders if needed (if so, use oversized pistons/rings). Crankshaft: Check for scoring and roundness. Polish or grind and use matching size bearings. 5. Reassembly 🧽 Preparation: Clean block and oil passages. Use assembly lube on bearings and cam lobes. Verify torque specs using the service manual. ➤ Bottom End: Install crankshaft with new main bearings. Torque main caps to spec. Install pistons with new rings (use ring compressor). Torque rod caps to spec. Check crank end play and rod side clearance. ➤ Top End: Install new head gasket. Install cylinder head, torque in sequence to spec. Install timing components (align marks carefully). Install rocker arms/lifters/camshaft (if removed). Adjust valve lash if applicable. 6. Final Assembly Install oil pump, oil pan, valve cover. Install intake and exhaust manifolds. Replace water pump and thermostat if old. Reconnect engine wiring and hoses. Reinstall engine into vehicle. Reconnect transmission, mounts, etc. 7. Initial Startup & Break-In Fill with fresh oil and coolant. Prime oil system (disable ignition and crank engine). Start and run at 2000 RPM for 20 minutes to break in cam and rings. Monitor for leaks, strange noises, or overheating. Change oil and filter after ~500 miles. ✅ Tips: Use OEM-quality gaskets and parts where possible. Keep your service manual nearby — torque specs and sequences are critical. Take photos during disassembly to help with reassembly. Label every wire and vacuum hose. If you need torque specs or diagrams for the G54B engine (e.g., head bolt torque or sequence), I can provide those too. Just let me know the specific year and model it's from. Link to comment Share on other sites More sharing options...
tux Posted June 13 Report Share Posted June 13 (edited) Chatgpt is ok for some stuff and terrible for other things. I have found it makes stuff up often. I was doing market research and gave it a bunch of PDF's and it made the wildest claims (all unsubstantiated) and couldn't cite it's source for decisions. Edited June 13 by tux Link to comment Share on other sites More sharing options...
nc_beagle Posted June 13 Author Report Share Posted June 13 I asked it to design a modern day version of the Conquest. While what it created looked to me more like a Dodge version of a Mustang, the quality of the image was really good. At first it just did a text response and noted some of what needed to be included in a modern version. I thought it was interesting. I wish I could insert the picture but I've had trouble posting images of any size. I didn't really give it a very long prompt. 🧬 Core Philosophy Retro-inspired sports coupe Turbocharged rear-wheel-drive performance Driver-focused cockpit Lightweight with modern tech and materials Competes with the Toyota GR86, Nissan Z, and Ford Mustang EcoBoost 🚗 Exterior Design Design Language: Neo-retro with aggressive wedge styling Key Features: Wide, low stance with flared fenders (like the original) Pop-up-style LED headlights (modern reinterpretation with flush-fitting DRLs) Deep front air dam, hood vents, and rear ducktail spoiler Frameless windows and pillarless roofline Available in classic metallics (Graphite Silver, Turbo Red, Starfire White) Wheels: 19” forged alloys (optional 20”), with a deep dish rear 🔧 Performance & Drivetrain Engine: 2.4L Turbocharged Inline-4 (based on Stellantis Hurricane platform) Output: 330–375 hp / 340 lb-ft torque Drivetrain: Rear-wheel drive (optional AWD performance trim) Transmission: 6-speed manual (standard) 8-speed automatic (optional) 0–60 mph: 4.5–4.7 seconds Top Speed: ~165 mph Curb Weight: ~3,200 lbs Chassis: Lightweight aluminum architecture Fully independent suspension Optional adaptive dampers and track package 🛋️ Interior Design Cockpit-Style Interior: Digital gauge cluster with analog-inspired boost and RPM gauges Alcantara and leather bucket seats with red stitching Retro-style toggle switches with modern infotainment 10.1” center touchscreen with wireless CarPlay/Android Auto Manual handbrake and short-throw shifter Options: Lightweight performance interior (deletes rear seats) Premium audio (Harman/Kardon) HUD and track telemetry system 🔒 Safety & Tech Advanced Driver Assistance (ADAS) suite: Blind Spot Monitoring Lane Keep Assist Forward Collision Warning Reversing camera with surround-view option Over-the-air updates and drive mode tuning 💰 Pricing (Estimated) Base RWD Manual: $36,000 Performance Manual: $42,000 AWD or Premium Trim: $48,000+ 🏁 Special Editions Conquest TSi “Turbo Legacy” Matte black with retro decals Bronze wheels Lightweight carbon accents 400 hp performance tune Limited run: 500 units Link to comment Share on other sites More sharing options...
techboy Posted June 14 Report Share Posted June 14 That response has you rebuilding the bottom end ... cleaning the block and putting in new bearings. If you just had a blown head gasket you could literally just pull the head and leave the block in the car and replace the gasket. Depending on the severity of the situation, of course, but that response is more of a total engine rebuild. 2 Link to comment Share on other sites More sharing options...
LizardKing Posted June 14 Report Share Posted June 14 Was this just for s**** and giggles or are you really looking into a full rebuild over a blown head gasket? X2 what @techboy suggested. To add to cylinder head inspection, look for any hairline cracks in between valves and sparkplug holes. 1 Link to comment Share on other sites More sharing options...
nc_beagle Posted June 14 Author Report Share Posted June 14 I just wanted to see what it would say. I'm working with a mechanic and am following his lead. Link to comment Share on other sites More sharing options...
BKB94 Posted June 14 Report Share Posted June 14 Its always good to get a health check on a engine before disassembly. I at the minimum would want actual oil pressure readings hot at idle and where the bypass is, compression test and leak down test. You will have 1 or 2 cylinders that will give you poor reading do to the HG blown probably but it will let you know the conditions of the rings, cylinders, valves, jet valves, head if cracked. A few minutes can give you a lot of info. 1 Link to comment Share on other sites More sharing options...
nc_beagle Posted June 16 Author Report Share Posted June 16 On 6/14/2025 at 5:26 AM, LizardKing said: Was this just for s**** and giggles or are you really looking into a full rebuild over a blown head gasket? X2 what @techboy suggested. To add to cylinder head inspection, look for any hairline cracks in between valves and sparkplug holes. Oh, I just realized what I'd used for a prompt. Well, to better answer your question, there is a blown head gasket, but we're using the opportunity to also modify a few things. It's possible the word "rebuild" overstates what I'm actually doing, but we are do have some changes in mind too. Plus the body work, interior restoration, and repaint. 1 Link to comment Share on other sites More sharing options...
tux Posted June 18 Report Share Posted June 18 For what I’ve used ChatGPT for it’s been hit or miss. my prompts always start with ”you are an expert in such and such field, I am requesting advice that has been well researched. Do not hallucinate or fabricate anything that you are not the expert in. Please cite all sources.” Then I ask my question with as much detail as possible Link to comment Share on other sites More sharing options...
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