Low coolant light dynasty

[RON KLINE]

"LOW COOLANT LIGHT" My 98 Monaco Dynasty has a 8.3 Cummins engine and the cooling system has a Volvo expansion tank. The tank has a low coolant sensor in it that screws in from top. the coolant light on the dash stays on while driving . There is only one wire going to this sensor the dash light goes out if I remove the wire and ground it. The sensor is a aluminum rod about 3/4 dia. by 7" long, wire screws in the center of sensor and is solid with no moving part in side , at least nothing rattles. I just can't figure how it is grounded. I went to a Volvo truck dealer they had nothing listed. I went on line and found the expansion tank with the threaded hole for the sensor but no sensor. If anybody out there has a 98 Monaco could you check your expansion tank to see if only one wire goes to sensor? I really want to replace the right sensor I don't want to drill any holes in this tank! Thank you for your time in this matter Ron

[vito.a]

Welcome to the forum!
Our Windsor had the same coolant sensor and Volvo expansion tank with a green cap. The new coolants coat the aluminum sensor and cause the light to come on. Remove the aluminum sensor and clean it with fine steel wool or Scotchbrite. I used to keep a spare sensor and as soon as the light came on I would swap sensors.
We even put one sensor in the lathe and bored a hole into it to increase surface area. It lasted marginally longer.
You may have to drop the tank slightly to get the sensor out of the top. It's pretty easy. Three 9/16" hex bolts and nuts.
Be careful not to overtighten the sensor and crack the plastic tank.

You will find a wealth of information in the Monaco Owners section of this forum.
https://www.irv2.com/forums/f115/
Hope this helps.

[Outbound]

IMHO it works just like your car, one wire.

[Mile Marker 42]

Originally Posted by RON KLINE

"LOW COOLANT LIGHT" My 98 Monaco Dynasty has a 8.3 Cummins engine and the cooling system has a Volvo expansion tank. The tank has a low coolant sensor in it that screws in from top. the coolant light on the dash stays on while driving . There is only one wire going to this sensor the dash light goes out if I remove the wire and ground it. The sensor is a aluminum rod about 3/4 dia. by 7" long, wire screws in the center of sensor and is solid with no moving part in side , at least nothing rattles. I just can't figure how it is grounded. I went to a Volvo truck dealer they had nothing listed. I went on line and found the expansion tank with the threaded hole for the sensor but no sensor. If anybody out there has a 98 Monaco could you check your expansion tank to see if only one wire goes to sensor? I really want to replace the right sensor I don't want to drill any holes in this tank! Thank you for your time in this matter Ron

I replaced my tank with one from Source Engineering and he told me those were simple/common ford sensors.