Need Some Help With My Dinosaur.

[partingclouds]

I've got a Yanmar 2QM20 diesel that needs a new water temperature gauge.
The engine is so ancient Yanmar no longer makes a replacement. It's a raw water/ fresh water cooled model. If anyone knows where I may find a substitute, or has one kicking around after repowering and no longer needs the gauge, i would like to buy it.

Thanks in advance,

Partingclouds

[Wotname]

Well I am designing a water temperature gauge for my even older Yanmar YSE 8 and in few days, I should have the basic circuit worked out - the genetic sensor only turned up today.

Presumably your existing gauge is electric, do you know if it is the sensor or the gauge that is faulty?

What was the range on the old gauge?

[Seabeau]

Any temperature gauge, of the appropriate type, i.e., mechanical or electrical, with its parameters within the required temperature range should work.

[jimbunyard]

Electric gauges have manufacturer specific ohm ratings; the senders must match the gauges. Some are compatible across manufacturers, but now a-days it's easier just to get the gauge and sender together. If you're not too particular, you can get a gauge and sending unit for a car for about 20.00 from an auto parts store, that comes with an assortment of adapters to fit various thread sizes. The cutouts for the gauges themselves are pretty standard, 2 1/8" if I remember correctly.

To get something weather resistant, you'll have to bite the bullet and pay marine prices, but at least the gauge won't leave rust stains if left out in the rain...

[RaymondR]

Originally Posted by Wotname

Well I am designing a water temperature gauge for my even older Yanmar YSE 8 and in few days, I should have the basic circuit worked out - the genetic sensor only turned up today.

Presumably your existing gauge is electric, do you know if it is the sensor or the gauge that is faulty?

What was the range on the old gauge?

Sensors have genes???

[Wotname]

Originally Posted by RaymondR

Sensors have genes???

Opps... try generic - bludi autocorrect

[Wotname]

Originally Posted by Seabeau

Any temperature gauge, of the appropriate type, i.e., mechanical or electrical, with its parameters within the required temperature range should work.

The problem is the OP has a raw water cooled engine than operates around 110F to 120F. This is at the very low end of almost all after market gauges.

Which is why I am making my own to operate with 120F at mid scale.

[partingclouds]

Thanks everyone for your answers. Im sure I can come up with a replacement now.

[bailsout]

I replaced mine on my 2qm15 raw water cooled with a mechanical gauge from the auto parts store. Waste of time since the thermometer begins at 110 or 120 and I have never been able to get the needle to move. The ocean temps here are low 50s to low 60s. My tach doesn’t work either. I just look for steam and flow out of the exhaust and sometimes put my hand on the valve cover when I’m pushing her hard.

[Simi 60]

Could always go this route and dial in your own temp
Great device, have the dual sensor on main and genset and would not be without it

ENGINE GUARD EG01/1 Single Temperature Sensor Kit - Engine Guard