I need to test whether the Vernatherm on my 1998 8hp Evinrude E8RECR is working properly as part of diagnosing engine running poorly (fouling upper cylinder). There are 2 parts on the Vernatherm: the main body and a small cylinder/pin that slides into the main body. The cylinder/pin has one end squared-off and the other end is a bit rounded Is my understanding correct that the rounded end of the cylinder/pin goes inside the main body? Also searching elsewhere in this forum I understand the cylinder/pin should grow longer out of the main body when the pair is placed in a pan of hot water after resting at ambient temperature. What temperature should the hot water be in the pan? How much longer should the Vernatherm assembly get when placed in the hot water? Does the Vernatherm work simply by Coefficient of Thermal Expansion of the pin/Main body? Or is there a gel/etc in the Main body that eventually wears out? All other parts of the Thermostat Assembly have been replaced not long ago, and I don't want to swap additional parts (i.e. Vernatherm) unnecessarily. Thanks in advance.
