Yamaha sterndrive thermostat

77searay197

Petty Officer 3rd Class
Joined
Aug 16, 2013
Messages
95
My boat cooled fine this summer but I just wanted to make sure my thermostat was facing the right way up? I tried to post a pic but it's saying it's too large. When I take the top of the housing off the top part of the thermostat has the point facing up and the sprng down. i know cars well but boats is something I've been learning about lol. Also does it matter if it's a 143 or a 160? It's a raw cooled freshwater boat and currently has a 143. Thanks
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Spring down is right. The expanding wax pellet in the cylinder behind the spring has to be in the coolant.

What temp does the gauge show when running? And what motor?
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
I think you're good. It's been a while since I had an I/O, so maybe a more current user will see this thread.
 
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