Capillary tubing is used in some refrigerators and other cooling devices instead of an expansion valve or other type of flow control device for the refrigerant gas. Be sure it's not the type with a very tiny pinhole inside instead of a full-diameter tube with about .015" wall thickness. 3/16" copper tube is also available in short lengths on Ebay. It takes about 3 feet of tubing to make the run through the water jacket and up to the rocker arm oil connector, and some special-design brass compression fittings are also needed to seal the tube at both sides of the water jacket.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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