1.8L OHC Engine Knock Noise - TENSIONER/Idler Pulley (SUB0482AP)
Reference number: SUB0482AP
1.8L OHC ENGINE KNOCK NOISE - TENSIONER/IDLER PULLEY
TECHNICAL INFORMATION TIP
KNOCKING NOISE IN 1800 OHC ENGINE
YEAR(S): 1985-93
MANUFACTURER: Subaru
MODELS: STD/GL/DL; Loyale
DATE OF ISSUE: June 1993
ISSUE & TIP
A knocking noise on 1985 and later Subaru 1800 overhead cam engines may be caused by a bad idler or tension pulley bearing or a loose timing belt. This engine has two timing belts, two tensioner pulleys, and one idler pulley, so there are a lot of possibilities.
Make sure the belts are properly tensioned first. A loose left timing belt will cause a knocking noise from the distributor area. If both belts are properly tensioned, try to determine which side of the engine the noise is coming from.
Once you've got it narrowed down, remove both timing belts and inspect the idler and tensioner bearings. It might not be a bad idea to replace them all along with two new belts at this time, unless you don't mind going through this exercise again some time in the future.
Courtesy of Import Service Magazine
with thanks to:
Dan Mayrin
Pacific Import Auto
Tacoma, Washington
REFERENCE NUMBER
SUB0482AP