Top Compression Ring: 0.40 mm – 0.60 mm (Wear limit: 1.50 mm) Scraper Ring: 0.30 mm – 0.55 mm 103.98 mm to 104.00 mm. Crankshaft Rod Journal Diameter: 89.98 mm to 90.00 mm. Valve Lash (Cold Engine): Intake Valves: 0.40 mm Exhaust Valves: 0.60 mm 4. Maintenance and Adjustment Procedures Valve Clearance Adjustment
Launched in 1979, the OM422 was initially derived from the earlier OM402 engine found in models like the 1626S. By increasing the cylinder bore from 125 mm to 128 mm and the stroke from 130 mm to 142 mm, Mercedes created a robust 14.6-liter workhorse. The naturally aspirated OM422 was groundbreaking, shifting its torque peak down to just 1,200 rpm, giving drivers incredible flexibility without needing to constantly downshift on inclines.
The manual covers the maintenance of the water pump, thermostat housing, and radiator. It includes procedures for pressure-testing the cooling system to diagnose internal leaks (often indicative of liner seal failure). om422 engine workshop manual
Regular valve adjustments ensure optimal engine breathing and prevent valve burnout. Adjustments must be performed on a cold engine.
Tightening torques for cylinder heads, main bearings, and connecting rods. Top Compression Ring: 0
Step 1: 100 Nm; Step 2: 200 Nm; Step 3: 330 Nm; Step 4: +90-100° Where to Find the Manual
According to data found on the Barrington Diesel Club and Scribd , the OM422 is part of the 400 series. V8 Diesel Engine. Displacement: 14.6 Liters (14,600 cm³). Bore: 128.00 mm. Stroke: 142.00 mm. The manual covers the maintenance of the water
The workshop manual covers several critical areas essential for maintaining the engine's performance. 1. Fuel Injection System
: Varies from 16.9:1 for naturally aspirated models to 16.25:1 for turbocharged versions.
If you are currently rebuilding or servicing this engine, ensure you have the precise manual for your engine subtype (e.g., OM422, 422A, 422LA) to access the correct torque specifications and technical data. Locate . Understand the firing order or valve adjustments .
: Cold engine specifications for both intake and exhaust valves.
