🚗 Classic Fault — Mercedes-Benz W115 (1968–1976)
Rich running after storage — stale fuel varnish
💰 Estimated Repair Cost
$30 – $100 USD
Parts and labour estimate
🔧 Tools Required
Carb cleaner, rebuild kit tools
📋 Overview
After extended storage, petrol breaks down and leaves varnish deposits throughout the fuel system and Zenith carburetors. The result is a car that runs poorly or not at all after being laid up.
🩺 Symptoms
- Black smoke
- running on fewer cylinders
- will not start after storage
- erratic idle
- orange varnish in float bowl
🔍 Possible Causes
- Varnish deposits in carburetor passages
- stale fuel
- blocked jets
🛠️ Diagnosis Steps
Drain fuel system completely. Inspect float bowl — orange or brown varnish confirms stale fuel.
✅ Most Confirmed Fix
Full carburetor strip and chemical dip. Replace all soft parts. Flush fuel system.
81% of users confirm this fix worked (25 reports)
🏷️ Parts Needed
Zenith rebuild kit; carb dip solution; fresh fuel
🔗 Other Mercedes-Benz W115 Faults
Own a Mercedes-Benz W115?
Share your experience with this fault — or report a different issue. Your knowledge helps other classic car owners worldwide.