Does anyone know when Merc decided to delete the thermostat from the Clamshell 50/ 60?
I ask becuase I decided to remove the exhaust / cooling jackets form the port side after I noticed one of the gaskets appeared to be being assisted by silicon sealant
- turns out it wasn't- it had been totally replaced by same
, however I was a bit surprised to find a thermostat in there....on an engine that no Microfiche seems to show one!
So, I had a "lateral thinking trawl" round good old Ishop's selection of info, and find that the manifold assy I have on my engine is off a "650" series machine. The livery on mine would hint it's a late 80s / early 90s. Makes me wonder - has it been rebuilt using parts off an older engine, or has someone done a cowl swap to make it look more modern / replaced a broken cowl?
So, does anyone happen to know the Clamshell thermostat history off the top of their heads? (or maybe a better question might be if I just rebuilt without the 'stat does it rely on the back pressure to make sure cooling water gets to corners it might otherwise not reach? (I hear they were prone to overheat, and I wonder if the 'stat was deleted to cure that issue?