Mercruiser 350 MAG MPI 5.7L TEMPERATURE

[benchircop26]

HI just a quick question.... engine is working perfectly but temperature is 135 Fahrenheit..... I was reading that it should be round 170 degrees Fahrenheit should I change the thermostat or is it normal to run at that temperature?

Thanks in advance

 

[alldodge]

HI just a quick question.... engine is working perfectly but temperature is 135 Fahrenheit..... I was reading that it should be round 170 degrees Fahrenheit should I change the thermostat or is it normal to run at that temperature?

Thanks in advance

Would be 175 or so IF (the big IF) you have closed cooling. If you have open cooling then there may not be an issue.

Do you have closed cooling and what is your serial number?

 

[Scott Danforth]

If your thermostat is broke or missing your temp would be low.

Or your gauge could be off

 

[Lou C]

Or if you have open cooling there could be a tiny grain of sand or piece of rust preventing the thermostat from closing all the way.

 

[benchircop26]

Hi Serial Number is OW170938 and i have open cooling i assume (raw water). Pumps sucks sea water.

But being at 135 degrees Fahrenheit will effect fuel consumption? or its normal operating temperature.

Thanks

 

[Scott Danforth]

135 is a bit low. wear increases, etc.

MPI usually like 160F

 

[dvosey264]

HI just a quick question.... engine is working perfectly but temperature is 135 Fahrenheit..... I was reading that it should be round 170 degrees Fahrenheit should I change the thermostat or is it normal to run at that temperature?

Thanks in advance

mine have run at 175 until I replaced thermostats one mercury part one sierra. the merc stat is right at 175 where it always ran and sierra is much lower so swapping out sierra. Why don't they publish important numbers like stat temp instead of just what part number it replaces.