DT55 Suzuki Water Temp Light

[nwslider]

I have a DT55 1986 Suzuki. The water temp light is on when starting the boat cold and stays on, good stream of water from the pee hole and water spitting out the back. Runs good and strong until you get to a certain RPM, don't have a tack but trying to throttle up over about 10mph the engine sputters as the rev limiter light comes on. Can run like this for over 5 min. should be up to temp, water coming out of pee hole is warm at best, no where near hot. Just had water pump and thermostat replaced week or two ago and this is the first time out, well second day, the first day it ran fine all day no problems. Kept the boat in the water at the marina and the next day this all starts up.

Is the next best thing to check the sensors? Were are the sensors? Is there a place online I can down load a service manual? My buddy and I are pretty good with a wrench, used to build and race our own drag cars.

Cheers!

 

[yoyo133]

Re: DT55 Suzuki Water Temp Light

Between #1 and#2 plugs is a black off oval shaped plastic piece held in by 2 screws. It is a water flow sensor and is most likely bad. Replace it or if you are brave or to test just unplug it. Water temp light should go out and consequently the rev limiter shouldn't kick in and the boat ought to run fine all else being ok.

 

[rodbolt]

Re: DT55 Suzuki Water Temp Light

yep its a flow sensor, that engine best I recall had no overtemp protection and yes there were issues with the float on the flow sensor.
easily tested once you get your manual.

 

[nwslider]

Re: DT55 Suzuki Water Temp Light

Thanks guys! you nailed it.

Removed the sensor and it was stuck open. Replace it with new one and cleaned up the old one tested with DMM seems to working so I have a backup to carry with me.

Cheers!

 

[wpalmisano]

Re: DT55 Suzuki Water Temp Light

i have a 1987 DT 65 with the same issues, and it happens frequently. The flow switch may not be your only issue ! If you had an issue with the impeller there could be plastic from the old one clogging passages, your thermostat could have plastic bits in it, be very careful if you intend to disable any alarm, you could burn the motor.
In fact I found your thread because I am about to rebuild the impeller yet again. This time I am going to do it myself.