🚗 Classic Fault — BMW (1982–1994)
BMW E30 M20 cylinder head gasket failure
💰 Estimated Repair Cost
$250 – $800 USD
Parts and labour estimate
🔧 Tools Required
Head gasket set, ARP studs, surface plate for head skimming, torque wrench
📋 Overview
The M20 six-cylinder engine head gasket fails, most commonly between cylinders 5 and 6 or at the water jacket passages.
🩺 Symptoms
Overheating. White smoke from exhaust. Coolant level dropping. Bubbles in coolant reservoir.
🔍 Possible Causes
Age and heat cycling. Previous overheating episodes. Incorrect coolant mixture.
🛠️ Diagnosis Steps
Chemical block test (colour change confirms exhaust gases in coolant). Compression test. Check for oil emulsion on dipstick.
✅ Most Confirmed Fix
Replace head gasket with quality MLS gasket. Have head skimmed and pressure tested. Replace thermostat and water pump simultaneously.
81% of users confirm this fix worked (34 reports)
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