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Block Tester

Combustion Leak Detector Fluid

Enough fluid for 16 tests using the Combustion Leak Detector tool


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Product Overview

The Block Tester® Combustion Leak Detector Fluid uses your coolant system to detect bad head gaskets and other combustion chamber defects. Works with virtually any liquid-cooled internal combustion engine or generator with a closed cooling system including: gasoline, diesel, propane, natural gas and other alternative fuels.

  • Container includes 16 oz. - good for 16 tests using the Combustion Leak Detector
  • Can be used with most fluid-based leak test equipment, including the Maddox Combustion Leak Detector
  • Works with any internal combustion engine including gas, diesel, propane, CNG and alternative fuel
  • Combustion leaks are indicated when fluid turns from blue to yellow
  • Non‐toxic, non‐hazardous

Important Information

  • Requires Combustion Leak Detector, sold separately.


Block Tester
Shipping Weight
1.20 lb.
16 oz.
Note: Specifications are approximate and subject to change


100% Satisfaction Guarantee! If for ANY reason you are not satisfied with this item, you may return it within 90 days for a full refund or replacement.