My auto parts store let me borrow a pressure tester for free, fill the reservoir with water and hook the tester, pump it up to the psi shown on the rad cap and you will see the leak if the presseure is dropping.

Dan

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81 240D 4speed with 300D engine
87 560SL
2005 E320
Yukon Denali
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850 Turbo Volvo
1996 Mustang
1984 Mustang race car
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