1990 omc 5.7 temp problems

[macorre4]

i have a 1990 omc 5.7 and i have already had the heads rebuilt put in a new thermostat changed the temp sensor and impellor and waterpump for the motor and after it warms up im getting a reading on my gauge of 3/4 hot at idle and it does not move from there can any one tell me what this can be and my gauge has no numbers only green and red and i also had the risers and manifolds cleaned and tested

 

[indybleck]

Re: 1990 omc 5.7 temp problems

Try a different gauge, or get some of those sticks that melt at different temps. Dash gauges are not very reliable. I had an issue with my 1988 5.7 oil pressure, pulled the sending unit and got a mechanical gauge checked it and the pressure is fine. Going to do the same thing with the temp gauge in the spring when I get it out of storage so I can see if my sending unit is bad or the dash gauge.

 

[drem312]

Re: 1990 omc 5.7 temp problems

How are you testing it on muffs or backed into a lake?

 

[macorre4]

Re: 1990 omc 5.7 temp problems

hi yes im going to replace the gauge i boiled some water and put the temp sensor in it at 180 degrees and the gauge was almost on red and at 140 it was in the middle so i ordered a new gauge thank u for that

 

[macorre4]

Re: 1990 omc 5.7 temp problems

i was testing it on muffs but the problem is the gauge