Operating Temp 5.0L EFI Alpha 1

[JR861]

Anyone know what the normal operating temp should be on this engine configuration? Just had mine out, and it is staying just slightly above 170. Is this normal? what is yours running at? I just bought the boat last august, and don't quite remember what it was doing last year. Seems to be doing good at this temp...no alarms, or anything. :huh:

 

[JR861]

Nobody?

 

[Banagy]

Must be close because mine reads just below 170 and no problems.

 

[hmonarch]

This must be a very closely kept secret of Sea Ray and Mercury. I cannot find anything in my Sea Ray Owners Manual or my Mercruiser #31 Service Manual.

I guess they don't want to stuck their necks out on this simple question that an owner would want to know.

Anyway, my 5.0 runs in the 170 to 173 degree range.

 

[Uplate]

I have 3 5.7's in ski and cruiser boats. All of them run right at 170.

 

[Wayne's World]

My 5.7's run at 175* in fresh water. :smt001

 

[JR861]

Thanks all...this gives me peace of mind.

 

[matthewmiller01]

I believe that is about where mine runs. I'll get a better look next time I am out.

 

[uraldyx]

Ran mine all afternoon Friday. Ran at a just over the edge of the 170 marker line. The book I have says 160 I think, but ran all last year at that 170 mark.

 

[matthewmiller01]

I was out yesterday cruising and pulling a tube. In 80* fresh water, the engine water temp ran 159* by Smartcraft. The gauge needle indicated ~ the same.

 

[04select200]

My 5.0 MPI runs @ 156. Two weeks ago I new something was wrong when it got up to 175 and then 190 with the alarm going off. I replaced my impeller last week and now it is back to running @ 156.

2004 200 Select 5.0 MPI / Alpha 1

 

[lope4946]

Mine runs at just over 170 as well. I think you are OK.

 

[Redhook98]

173 here on both motors. I think it's OK. Going to put in new 160 thermostats and see if it lowers at all. Don't think it will, but at least I will have shiny new thermostats installed. Plus it makes the boat go faster. :smt043

 

[ultratiger89]

Mine has two temp senders I think most do). One sends the signal to the gauge on the dash and it reads ~190°. The other sender goes to the computer and it reads ~160° while running. I checked this by using a laser temperature gun aimed at the t-stat housing. I also had my mechanic check it with his computer. The one to the gauge is obviously wrong. The thermostat is a 160° thermostat. I have a 350 mag. As long as the gauge doesn't peg out and the hot horn goes off, I don't worry about it.

ETA: The sender for the gauge is around $15 and the one for the computer is around $80, so it's obviously a much better sender.