1975 Mercury 20hp What's that weird noise ? Where is the thermostat? Is water going to pump?

In this video we get this old 20hp pumping water but now we have a mysterious sound
Follow the links below for some of the items used in this video:
AMSOIL FULL SYNTHETIC Gear Oil 75W-90 1 Quart amzn.to/3xyjq3d
Heavy Duty Push Button Momentary Start Switch amzn.to/3cUjYso
Petrol Engine Cylinder Compression Tester Kit amzn.to/3iVme6C
marine grade wiring amzn.to/3qfOWAK
Super Clean 101723 1gal. Super Clean Degreaser amzn.to/3iSZp38
Electric starter
amzn.to/3qx0PlJ
CRANK N CHARGE Starter Solenoid Replacement For Johnson, OMC, Evinrude Outboard Motor
amzn.to/3dhgr7o
wiring connector kit: amzn.to/2Um5N91
Lucas Marine Grease amzn.to/3yiKncn
Carb kits:
amzn.to/3f06H33
Impeller:
amzn.to/2S2IXls
Johnson/Evinrude/OMC New OEM GASKET fuel pump
amzn.to/33PdzK0
Aluminum 3 Blade Propeller - RH, 10.5" Diameter x 11" Pitch x 14-Spline
amzn.to/3wjFkH3
Aluminum 3-Blade Propeller - RH, 10.1" Diameter x 13" Pitch x 14-Spline:
amzn.to/3x18avX
Aluminum 3-Blade Propeller - RH, 10" Diameter x 15" Pitch x 14-Spline:
amzn.to/3clMEtM
Video equipment used
Canon EOS M50 Mirrorless Vlogging Camera Kit with EF-M 15-45mm Lens, Black
amzn.to/3tcSCTE
Comica BoomX-D D2 2.4G Wireless Lavalier Microphone System Digital 1-Trigger-2 Wireless Microphone Transmitter & Receiver SLR Clip-on Micro phone,Lav Mic for Smartphone Camera Podcast Interview
amzn.to/3edmYB4
email me at
[e-mail]
mail me at
RMD Creations
PO Box 387
Wellman, IA 52356