Want to add gauges

[Joe]

I have a Yanmar 2GM raw water cooled engine. The sensors are idiot lights with a horn. I have added a voltmeter and a oil pressure guage.However, there is only one spot for a water temp sensor. Is it possible to install some type of metric threated T into which I can install the sensors for the idiot light and horn as well as the sensor for the guage? The guage sensor is sae thread while the engine block threads are metric. Advise is appreciated.

 

[Howard Morton]

A possible fix

Joe:My guess is that you're going to have to have the SAE/Metric T custom made at a machine shop. You may however get lucky with the thread sizes as follows: First determine the size of the metric threads you need for the engine. If you can find a (female) SAE T fitting just a bit smaller than the required metric threads, you may be able to drill it out to the proper size to accept a metric tap of the correct size. You will probably need a metric nipple to connect the T to the engine. I have found that the flat-sided brass T's often have a bit more metal to them than the cast ones, and hence you may have better luck there.Of course, all this depends on being able to find an appropriately sized brass T. Good luck.Howard

 

[Ernie]

Another way

I have a 3GMD engine which probably has the same water jacket where the sender is mounted for the temp-alarm as your 2GM. On my engine I removed the water jacket and drilled/tapped a place for the water temp sensor using a standard SAE tap. This works better than a T because there is no assurance of getting water to the T and to both sensors, besides there is not much room for a T, but underneath the water jacket there is plenty of room for the temp sensor. Locating the sensor at the bottom of the jacket provides a good path for plenty of water to pass by the sensor and ensure a good reading and does not interfere with the alarm temp sensor. This has worked fine for me for the past sixteen years.Ernie

 

[Roy Mosteller]

Water Sensor For 2GM20F

Are you certain the threads are metric? My Yanmar mechanic added a sensor to the 2GM20F on my 30T (1991) and he assures me it was 3/8" threads. He installed a nipple and T where the water hose leaves the thermostat housing. Works great for both gauge and original buzzer sending unit. I can supply photograph and instructions on my installation if it would be helpful. If you want them send e-mail to me at roynjean@home.com