That model does.
Pumps when it needs too once warm then stops till it needs to again. Bloody stupid idea as you are forever panicked when you look over and see nothing!!
My advice take the stat out and it will pumps forever. Will run a little cooler but won't harm it. You can replace the stat with a restrictor washer (like a penny washer with a preset hole in it to slow the flow down) so that it runs at right temp and pumps all the time.
Peter @ Boatsandoutboards4sale ~ email@example.com
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