Fixing Excessive Oil Consumption: DIY Valve Guide Seals for Classic Benz M117 M116 M103 M104

This video is designed to help guide you through a valve stem seal replacement. Severe oil consumption of more than 1 - 1.5 qts per 1000 miles lead to fouling of spark plugs and catalytic converter damage not even mentioning it is not nice to the environment. Here are a few tool recommendations of the tools used in this video that made the valve stem seal replacement much easier or even possible. Valve spring compressor: https://tinyurl.com/23373v9n Combustion chamber pressurization: https://tinyurl.com/nbrzphy2 Pliers: https://tinyurl.com/4wzs5dmu Spark plugs: Champion Spark Plug Part Number: 6265-09023475 Brand: Champion Notes: Copper Plus -- Plug Type N11YC; Non-Resistor Type; Gap 0.032in; OE Type https://tinyurl.com/dmts39f5 In this technical guide, Ralf from Stray Benzes provides a detailed walkthrough for replacing valve guide seals on Mercedes-Benz M117, M116, M103, and M104 engines. This common repair is essential for addressing excessive oil consumption, fouled spark plugs, and protecting the engine's catalytic converter from long-term damage. Video Chapters [00:01] Introduction: Why failing valve guide seals cause high oil consumption. [00:46] Tools & Parts: Spark plugs, valve seals, magnets, and specialized jigs. [02:57] Special Equipment: Using compressed air and a leakage tester for safety. [04:09] Preparation: Removing the valve covers and air filter housing. [05:51] Top Dead Center (TDC): Finding the correct crankshaft position for each cylinder. [08:35] Technical Theory: Understanding the assembly via cross-section diagram. [09:40] Component Removal: Pushing down the valve spring and extracting rocker arms. [10:44] Seal Extraction: Using pliers to remove old seals and installing guide savers. [12:04] Reassembly Logic: How to know if the valve stem is correctly seated. [13:18] The Magnet Trick: Safely fishing out the small valve keepers. [14:43] Engine Protection: Why you must plug oil drain holes during the process. [15:34] Cylinder Bank Differences: Dealing with fuel lines and brake booster vacuum. [17:12] Final Tip: Finding the correct non-resistor spark plugs for classic engines. Video Summary Ralf addresses the problem of engines consuming up to two quarts of oil every 1,000 miles, which is often a direct result of hardened valve guide seals. He emphasizes that this procedure is essentially the same for both V8 and Inline-6 gasoline engines of this era. Key Technical Highlights: Safety Mechanism: To prevent the valves from falling into the combustion chamber during the repair, Ralf uses compressed air and a leakage tester to hold the valves closed while the springs are compressed. Critical Precision: Each cylinder must be worked on individually when it is at Top Dead Center (TDC), with both lobes of the camshaft pointing away from the lifters. This ensures the piston is at the top of its stroke as an extra safety measure. Protecting the New Seals: When installing new seals, Ralf uses a "valve guide saver" (a plastic protector) to prevent the sharp edges of the valve stem from tearing the delicate new rubber during installation. Hardware Management: The small "keepers" (valve cone halves) that hold the spring assembly in place are notoriously easy to lose. Ralf recommends covering all oil drain holes in the head with rags so that if a keeper is dropped, it doesn't fall into the oil pan. Rocker Arm Inspection: While the valve covers are off, it is a good time to inspect the rocker arms and camshaft lobes for deep grooves or excessive wear, which could necessitate more extensive engine work. Spark Plug Warning: Ralf notes that many modern "compatible" spark plugs contain a resistor (marked with an 'R') that can negatively impact the performance of these older ignition systems. He advises sourcing original-spec non-resistor plugs. Video URL:    • Fixing Excessive Oil Consumption: DIY Valv...