Mercedes-Benz
300E
6

Check Belt Tensioner When Replacing Water Pump on Mercedes-Benz 300E

Problem Description and Possible Solution

A coolant leak may develop from the water pump. When replacing the water pump, the drive belt tensioner should be inspected and most likely replaced as well.

Problem Data
RepairPal Verified
Average mileage: 182,500 (130,000–235,000)
4 model years affected: 1990, 1991, 1992, 1993
6 people reported this problem
Comments
Viewing 1 - 2 of 2 comments
Belt became loose & inspection revealed rubber bushing detached from tensioner. Full replacement fixed problem.
I've had to have the water pump replaced 3 times beginning at 130,000 miles every other year. After the water pump was replaced the tensioner had to be replaced.