Coolant temperature monitoring for Yanmar 3ym30

[Sailor_D]

I like at add a coolant temp gauge to my Yanmar 3ym30 with comes factory equipped with an over temp switch/ buzzer only. Unfortunately, all openings for temp sensors are used because of the water heater that is connected to the coolant system.
VDO offers temp sensors with the additional overheat warning contact, but not for the 16mm thread and the 93C switch that is needed. With a combined sensor/switch one could simply replace the current temp switch. Anyone, knows where to get fitting coolant sensor / warning contact for the Yanmar 3ym30 diesel. Your help is appreciated.

 

[Ralph Johnstone]

VDO offers temp sensors with the additional overheat warning contact, but not for the 16mm thread and the 93C switch that is needed.

All the same problems I encountered when I was installing my temp. sensor (for a 2GM20F) years ago. Seeing as how the water heater uses one of the ports, I decided to tap into the heater hose.

The 1/2" brass T is in the supply line to the water heater so it sees engine temp. The green wire is soldered to the brass T as the ground (didn't have any black, gotta replace with the right colour one of these days). The green wire is lead to the engine block as the hose won't conduct to ground. The wire from the temp. gauge is attached to the temp. sensor, which is screwed into the far side of the brass T.

 

[seadaddler]

Look here in this forum and you should fine same setup for the 3GM30
only the tee is up top at the thermostat which I have on my 3YM30 and works great,
I am away from Fl. up in NY and no photo with me.
Nick

 

[John T1594]

Several years ago I installed a CruzPro T30 digital temperature gauge with alarm on my 2000 H340 with the Yanmar 3GM30F engine. I replaced the original buzzer only engine temperature sender with a Telflex 3/8” sensor. The alarm on the CruzPro was set at 190F. I used the original blue/white wire from the old engine sensor to the new gauge in the pedestal. The ground for the gauge was tapped into a common ground wire on the fuel gauge and the Positive wire was tapped into the Positive lead on the ignition switch. The gauge worked great and was calibrated for the Telflex sensor (U-4). I have used it for several years now and it gives me good continuous reading of the engine temperature. This installation avoids the problems with dual sensors, T-fittings, other brass pipe fittings that tend to break, etc. and gives me accurate engine temperature readings with the protection of an over-temp alarm.