1984 Evinrude 115 - What temp should it be running at?

[Matt Mann]

I have an infrared thermometer. What temp should the engine be at the heads? I am not sure my cooling system is working, so I don't want to run it too hot. I keep waiting for water to pee out of the holes just below the cowl, but don't want to wait so long as to damage the engine.

 

[oldcatamount]

Re: 1984 Evinrude 115 - What temp should it be running at?

The water should be coming out of the pee hole in about 5 to 10 seconds after the motor starts up. It's very seldom immediate. The operating temp should be around 140 degrees. If you can touch the heads (with the motor running) with your finger and hold it there for a few seconds, it should be OK but, use your infared sensor to be sure.

 

[Tim R W]

Re: 1984 Evinrude 115 - What temp should it be running at?

I have the same problem but the thermostats won't open till 130 to 150 at least that is what I have been reading, I have water getting to the thermostats out of both heads but have not had water come out below the cowl yet did you find out at what temp yours was opening up?

 

[emdsapmgr]

Re: 1984 Evinrude 115 - What temp should it be running at?

The stats are set to open at 143. When idling in a warm lake in the summer, the temps can creep up to 155. The engine sounds the horn for an overheat at 212 degrees. The hot horn will silence when the engine temps get back down to around 175-still too warm for normal operation in my opinion. The powerhead temps will go down dramatically when at planing speeds-when the pressure relief valves open and the powerhead gets flooded with cool water.

 

[Tim R W]

Re: 1984 Evinrude 115 - What temp should it be running at?

Okay then there is no water out of the stats until there is 143 degrees? That is how I see it I was running mine in test tank for 15 minutes and top cylinders were around 110 so the stats never opened the whole time I assume the water is pumping thru to the prop and the stats are more of a fail safe than anything else and they are only needed when or if a overhaet situation is present.

 

[emdsapmgr]

Re: 1984 Evinrude 115 - What temp should it be running at?

The water will flow out of the telltale anytime the pump is working. Basically, little water will flow out of the block at idle unless the stats open. There is a (minimal) trickle which will flow through the pinholes(s) in the valve body of the thermostat housing when the stats are closed. If the stats don't open, you will eventually get an overheat at idle. Large amounts of cooling water will flow through the powerhead when the pressure relief valves in the thermostat housing open. Two things can cause the pressure relief valves to open: when you go on plane or when you rev the engine sitting on the trailer. It is possible that your stats are stuck open if you never saw 140 on the laser temp gauge. Theoretically, when in the lake, the cyl head temp at idle should vary between 143 and 150 or so, as the stats open and close periodically. If the engine runs at 110, it is running too cool. Cool running engines have poor combustion, tend to accumulate carbon around the rings-both of which can be long term problems.