Home measurements #3

The last measurement I was able to make today was the clearance on the connecting rod big-end. In the photo:
(1) Is the connecting rod -- connects the crank to the piston
(2) is the oil dipper -- it helps to splash oil around and lubricate stuff (this engine has no oil pump)
(3) the crank (if the piston is the heart, this is the legs)
(4) the rod little-end (where the piston goes)

I like doing this measurement because it's like opening up a present -- you never know what you're going to get until you take it apart. In the photo above I've installed a small strip of plastic called a "plastigage" inside the joint between the connecting rod big-end and the crank. I've re-installed the end-cap (where the screws are, near the dipper (2) ) with the plastigage in place. I torqued the screws to their spec -- this squishes the plastic strip. Take it apart again and ...

... a paper gauge that comes with the "plastigage" kit tells you the clearance. The more it's mushed, the smaller the clearance. Cool! Result? You can't see from the photo but the width of the smushed plastic shows about 0.003" of clearance -- right on the wear limit called for in the Kohler manual. Right on the edge. This is one measurement that is OK and we don't need to do anything about.