97 Johnson 90 slow mode no lights

[Gboats91]

I have a new to me 18ft cc with a 97 johnson 90 J90ELEUA.

It idles and nice will run well for 5-10 minutes and then goes into slow mode. When this happens, the overheat light does not come on.

Initially, since the light did not come on, i did not think it was overheating. It ran great below 2500rpm.

I pulled the 2 temp sensors and both appear to be functioning(open at room temp, close around 230, open back around 175 approx)

I will confirm with an infrared thermometer this weekend if it is in fact overheating or not.

Water stream is good. Fresh gas, new filter, new plugs.

What do you guys think?

 

[Chris1956]

Well, if she is not overheating, yet she is in SLOW mode, the problem is in the wiring or sensors. First step is to disconnect both temp sensors and see if she stays out of SLOW. If not, ohm out the wiring to see if it grounds somewhere.

On a '97, I would look at the wiring harness for melted wires, near the motor (port side) and under the dashboard.

 

[boobie]

You could also have a bad power pack.