Why is my engine pulley wobbling and making a grinding noise?
A wobbling engine pulley is often caused by aged, degraded rubber in components like the harmonic balancer or crankshaft pulley failing completely, which can throw the belt and cause grinding sounds underneath the car. This makes it difficult to determine whether the failure stems from normal wear on old parts or a component installation error.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1visually inspecting components for movement between the crank and outer pulley
- 2Replacing the failed harmonic balancer and inspecting the engine system for related wear or secondary failures.
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“it looks like the belt around the pulley is wobbling a little bit and getting underneath the car makes it sound a little bit more like grinding.”source ↗
“So I got the tensioner installed and the belt went to start it and next thing i know the crank shaft pulley ( the outer part ) came off completely . So wondering if this was due to aged and degraded rubber or if it was a user error ...”source ↗
Where this came up
People with this problem also raised
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