<center><img src="http://pictureposter.audiworld.com/57225/headgasket_leak_detector.jpg"></center><p>You load the 2 chambers with the blue magic fluid, then put the whole "turkey baster" assembly over the coolant tank, and with the engine running, slowly squeeze and release the bulb to allow the steam in the coolant tank to be drawn up through the blue fluid.

They come on ebay all the time, but you'll also find them from any number of tool sources.

The instructions say to test the operation by filling it with the blue fluid, placing the business end in the cup of your hand and then exhaling on it while you operate the sqeeze bulb. It's so sensative, it turns yellow from your breath.

Then you continue squeezing the bulb (while not breathing on it) and the fluid is re-oxygenated and turns blue again, all ready for testing your engine.

They are all made by the same company....in Germany I think.<ul><li><a href="http://cgi.ebay.com/MATCO-Head-gasket-leak-detector-tester-Porsche-944_W0QQitemZ120226822770QQihZ002QQcategoryZ43989Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem">Headgasket Tester</a></li></ul>

These are available from a whole bunch of vendors, so I'll bet you'll find them once you dig in and start looking.

<ul><li><a href="http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm">http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm</a</li></ul>