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Coolant Caps

2019-01-09 - ipd Staff

Volvo Coolant Caps

Disclaimer: Direct from ipd’s Tech Tip archive!  This tech tip contains information from previous publications.  Products mentioned may not be available or the information may not be accurate due to changes in supply, manufacturing, or part number association.  Please contact ipd Customer Support if you have further questions  info@ipdusa.com

Since the beginning of the 2 series and through the XC90 coolant caps have had the same basic design. Although colors vary from white to black to green to gray, they all have the same vulnerability. Small horizontal cracks will tend to form on the upper portion of the cap hat. This phenomenon is a result of over tightening. The cracks form when the rim of the expansion tank presses up on the top of the cap due to the over tightening. When replacing yours be sure to get the correct color since each different color corresponds to a different pressure cap. In some cases mysterious and untraceable coolant loss has been contributed to a cracked cap leaking pressure and vapor. When inspecting the cap, look for hairline cracks and distressed plastic evident by white streaks at the point of stress. If necessary replace the cap and consider a new thermostat and coolant service. Summer is just around the corner.