![KRC Adjustable Idler Tensioner Assembly (604 Crate) KRC Adjustable Idler Tensioner Assembly (604 Crate)](https://cdn.performancebodies.com/pbfilestore/PartsCatalog/imgPar559410_1.jpg)
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• KRC adjustable idler tensioner assembly prevents belt slippage due to deceleration of a mechanical fan
• Available for 604 Crate or 602 Crate/standard SBC engines
Kit Includes:
Idler tensioner bracket, hardware and spacers
**604 Crate engines have a thicker timing cover that requires the water pump to have a 3/8" shim behind it, therefore changing the bolt lengths into the water pump**