My KTM 790 Has a Problem Nobody Talks About!

Coolant disappearing, strange residue under the oil cap, and only 7,000 km on my KTM 790 Duke! Is it just condensation, or something much more serious? In this video, we investigate coolant contamination in the KTM 790/890 LC8c engine and perform a complete water pump shaft seal replacement, step by step! I'll show you how to disassemble the water pump, inspect the damaged seal, install a new one using a simple 3D-printed tool, and reassemble everything correctly. We'll also cover cooling system bleeding, coolant refilling, and flushing contaminated engine oil. Whether you're experiencing coolant loss, water in your engine oil, or simply looking for a detailed KTM 790/890 water pump seal replacement tutorial, this video covers the entire procedure! But there's more! We also sent an oil sample to a professional laboratory to find out if the contamination caused any engine damage. Let's see what the results reveal! ————————————————————————————— ⚙️ PARTS USED — KTM 790/890 WATER PUMP SEAL REPLACEMENT 🔧 OEM KTM Spare Parts (Not Sponsored) • Water Pump Radial Shaft Seal: 0760001534501 (Replaces 0760153459) 🔗 https://ktm-versand.de/en/spare-parts... • Water Pump Cover Gasket: C90035053100 (Replaces C90035053000) 🔗 https://ktm-versand.de/en/spare-parts... • Wear Bushing: C77236072120 🔗 https://ktm-versand.de/en/spare-parts... • O-Ring (9 × 1.5 mm): C07700900151 🔗 https://ktm-versand.de/en/spare-parts... • Copper Sealing Washer (6 × 10 × 1 mm): C0603061001 🔗 https://ktm-versand.de/en/spare-parts... • Water Pump Impeller Bolt (M6 × 13): 0024060136S (Optional / Recommended) 🔗 https://ktm-versand.de/en/spare-parts... 🖨️ FREE 3D-PRINTED SEAL INSTALLATION TOOL Download the STL file for the installation tool I designed and used in this tutorial! 🔗 https://makerworld.com/it/models/3519... ————————————————————————————— 🔬 Special Thanks - Mecoil Diagnosi Meccaniche A big thank you to Mecoil for kindly providing the professional oil analysis featured in this video free of charge! Mecoil specializes in professional oil analysis, contamination detection, and mechanical wear monitoring. Check out their services: 🌐 https://www.mecoil.net/ ————————————————————————————— 🛠️ KTM 790 / 890 Oil Change Tutorial Want to learn how to properly service your KTM LC8c engine? Check out my complete oil change tutorial, including useful tips, torque specifications, and service reset instructions! 🔗    • KTM 790 / 890 Oil Change Tutorial | Do It ...   ————————————————————————————— 📖 How to Get the Official KTM Workshop Manual:    • How to Get the Official KTM Worksop Repair...   ————————————————————————————— 🔎 Need to find OEM spare part codes? Use the official KTM spare parts finder: https://sparepartsfinder.ktm.com/ ————————————————————————————— 📧 Questions? Comments? Business inquiries? Email me at askcesarefloris@gmail.com ————————————————————————————— 🔧 I share tutorials on engine swaps, wiring, CAD, VAG builds/tuning, KTM motorcycle maintenance and modifications. 🪛 📸 Instagram: @cesarefloris ————————————————————————————— ⚠️ Disclaimer: This video is for informational purposes only. Always follow the official workshop manual, use the correct torque specifications, and verify component compatibility for your motorcycle. You are responsible for any work performed on your vehicle. ————————————————————————————— ⏱️ VIDEO CHAPTERS 00:00 Introduction – Coolant in Engine Oil?! 00:49 Possible Causes of Coolant Contamination 02:23 Cooling System Pressure Test 03:16 Draining & Inspecting the Engine Oil 04:04 Sending the Oil for Laboratory Analysis 05:14 Water Pump Disassembly 06:01 Finding the Damaged Water Pump Seal 06:58 Could the Balancer Shaft Be the Problem? 07:18 Measuring Balancer Shaft Play 08:26 KTM's Response – Is the Shaft Play Acceptable? 09:13 Updated KTM Water Pump Seal 10:05 Inspecting Oil Filters & Metal Particles 10:34 Laboratory Oil Analysis – Did It Damage the Engine? 12:44 KTM 790/890 Water Pump Shaft Seal Replacement 13:54 Free 3D-Printed Seal Installation Tool 14:32 Water Pump Reassembly 15:20 Cooling System Refill & Bleeding 16:36 Flushing Contaminated Engine Oil 17:41 Oil System Priming & First Startup 18:06 Engine Heat Cycle & Final Flush 18:41 Final Thoughts & Conclusions ————————————————————————————— #KTM790 #KTM890 #LC8c #Adventure #Duke #KTM