David Vandercook
Senior Member
Well, I got a combustion leak test kit with O'Reilly's tool loaning thing. I followed the instructions, drained some coolant so it was a few inches below the filler, warmed the engine up and put the tester in with some fluid. When the water pump started the coolant rose up to the tester and coolant came into the tester. It erupted again when I shut it off. How can I prevent this and get reliable results with the tester?