Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

[Manoj77]

Anyone know please at what temperature should a thermostat open on a Yamaha year 2000 4HP 4 Stroke? My OB discharges water through the tell tale at 120 degrees fahrenheit. The thermo was changed but the thermo is not a 'genuine' Yamaha thermo so I want to make sure I have the correct type of thermo installed. Thanks.

 

[99yam40]

Re: Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

all Yamaha tell tail streams I have felt were just warm, not hot
Not sure the stat would affect tell tail temperature as it just tells if pump is pumping water
2 strokes I do not think it would But never played with a small 4 stroke

Just read your other post so if he is correct then it must be OK
My C40 stat starts opening about 120 and full open at 140.
It would be a good idea to get a service manual for your motor

 

[Manoj77]

Re: Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

The tell tale outstream line is right 'after' the thermostsat. So once the stat is open water flows out and it (the stat) opens at 120 degrees.

 

[Johnny Otter]

Re: Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

According to the manual, your thermostat is a 12411 and should open at 122 degrees.

Regards

John

 

[Manoj77]

Re: Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

Thanks John, The link you gave me is only for 2 stroke motors unfortunately. But Ive done more homework and since the discharge is after the stat opening then my water temp seems ok. Some OBs have a telltale before the stat which means the discharge will be much cooler. Mine was measured at 123 degrees and my stat opens to the telltale at 120 degrees. Very odd for me as my last OB was a Tohatsu and it was tepid at most.

 

[Johnny Otter]

Re: Thermostat rating for Yamaha year 2000 4HP 4 Stroke.

Sorry about the link - I realised after I posted it was for 2 strokes, and tried to delete it. I must have failed miserably .