Having possible troubles with a thermostat from a two-plunger injection pump (M127 engine). If placed in a pot of boiling water, how far should the pin extend? I am trying to determine if a defective thermostat is the cause of my fluctuating idle. My mechanic tried the boiling technique, but did not get the pin to move at all. I would not think that it would move too much, but am curious if anyone has any experience in this regard (new thermostats from the dealer as you would expect, are horribly expensive). Thanks for your time, Paul