Question on thermostat Yamaha S150??

[Grady175]

I was out with a friend on his Adventure 208 and we noticed water coming out of the cowling on his 1999 Yamaha S150 TXRX. He later send me the attached photo. It looks like a thermostat but I was wondering if anyone has any experience with this and any tips on replacing. Also, what may have caused the failure.

Thanks

[/img]http://home.comcast.net/~smgodin/pwpimages/yamaha.jpg

 

[Grady175]

Another try on the image:

http://home.comcast.net/~smgodin/pwpimages/yamaha.jpg

 

[catch22]

That's the "poppet valve". Yamaha actually calls it a "pressure control valve".

Here's a link, (you can zoom in) - http://www.boats.net/parts/search/Yamah ... parts.html

Replace all the related parts, (21 thru 25). 25 is the "bypass cover", (that broke).

Don't know why it broke apart like that. Maybe water was trapped during the winter, (especially if he left it tilted up)... froze, expanded and cracked it. Either that, or it's some major corrosion.