Adding Temperature Gauge to MD 2020

[Goofeyfoot]

Hello all:

I have an older, maybe 20 years old, Volvo MD 2020 diesel in my sailboat.

The engine runs OK, but it has just an idiot light instead of a temperature gauge.

On the Fourth of July I had a major overheat situation. I heard two dings from the engine panel and then the engine stopped dead.

I wanted to add an engine temperature gauge.

What’s the easiest way to upgrade gauges like that?

I know some of the newer chart plotter’s have gauges on them, but I don’t know whether those work with all engines or just newer ones.

There’s probably a simple solution, or at least I hope so.

Thanks.

Michael

[wingless]

LOT of options, here is one.

[a64pilot]

You need to find a plug in the Cooling system, on my Yanmar it was right beside the Thermostat I think, once you locate that it’s a simple matter of unscrewing it and screwing in a sending unit. Otherwise you will have to drill and tap, there are contact sensors, but I see them as temporary things myself.
I went with a traditional round gauge, I also added an oil pressure gauge, for the same reason.

Another possible option is often there are combo sensors that contain a switch for the light and a sending unit for a gauge.

The gauges on a plotter are designed to be networked with the CanBus of newer electronic controlled motors, it’s possible to do that with an old motor, but in my opinion not worth the expense

[slug]

Originally Posted by Goofeyfoot

Hello all:

I have an older, maybe 20 years old, Volvo MD 2020 diesel in my sailboat.

The engine runs OK, but it has just an idiot light instead of a temperature gauge.

On the Fourth of July I had a major overheat situation. I heard two dings from the engine panel and then the engine stopped dead.

I wanted to add an engine temperature gauge.

What’s the easiest way to upgrade gauges like that?

I know some of the newer chart plotter’s have gauges on them, but I don’t know whether those work with all engines or just newer ones.

There’s probably a simple solution, or at least I hope so.

Thanks.

Michael

Adding additional sensors is easy . Some sensors have two outputs or you can purchase a tee and use two senders

Ask you engine shop for suggestions



The most important modern sensor is exhaust temp

It instantly fires off.... long before your engine begins to overheat ...when water flow is restricted

[doublewide]

Good question. Good answers.

Better question: how do I get warning BEFORE my engine overheats? Answer: Add an EXHAUST temperature monitor. This is much simpler than adding an engine temperature gauge. Just strap the sensor around your exhaust hose near the raw water injection point, mount the alarm buzzer where you prefer, wire it and power it up and bob's your uncle.
Maybe you want both an engine temperature gauge and an exhaust temperature alarm, but if I had to choose one, I would choose the exhaust temperature alarm.

[a64pilot]

How would an exhaust temp alarm help if your thermostat froze shut?
An exhaust temp alarm is to alert you to a restricted raw water flow, it’s not to tell you anything about engine fresh water temp.
Last year I had an impeller fail and all but one paddle tore off, Exhaust noise got loud and it was obvious that I had lost most raw water flow, but engine temp never moved.
Flip side of that is a failed thermostat can cook a motor, but the exhaust water stays nice and cool.

They are different things

[doublewide]

By George! I think you are right. Thank you.

[Sailshabby]

Originally Posted by Goofeyfoot

Hello all:

I have an older, maybe 20 years old, Volvo MD 2020 diesel in my sailboat.

The engine runs OK, but it has just an idiot light instead of a temperature gauge.

On the Fourth of July I had a major overheat situation. I heard two dings from the engine panel and then the engine stopped dead.

I wanted to add an engine temperature gauge.

What’s the easiest way to upgrade gauges like that?

I know some of the newer chart plotter’s have gauges on them, but I don’t know whether those work with all engines or just newer ones.

There’s probably a simple solution, or at least I hope so.

Thanks.

Michael

Michael - I’ve been in just about every liquor store and 7-11 on the East coast and have NEVER seen a temperature gauge on a bottle of MD 2020- oh, wait, a Volvo. Never mind...

[dick sargent]

Not exactly on subject, but I installed a pyrometer in the dry side of the exhaust manifold. It told me a lot. When the normal running temperature increased because the bottom or prop was dirty I'd back off the rpms to reduce the exhaust temp. to the safe range.

[slug]

Originally Posted by dick sargent

Not exactly on subject, but I installed a pyrometer in the dry side of the exhaust manifold. It told me a lot. When the normal running temperature increased because the bottom or prop was dirty I'd back off the rpms to reduce the exhaust temp. to the safe range.

I’ve mostly used dry exhaust temp to operate adjustable pitch hundersted propellers

The exhaust temp is very sensitive and gives an accurate report on engine operating conditions

[DougR]

It’s a fairly easy job to add a temp gauge to a 2020 engine. There is an existing hex head plug on the side of the heat exchanger tank which is for installing a temp sender. The wire for the sender is already in the engine harness......it’s zip tied with the wires on the back of the alternator...light brown. The light brown wire will run to the connector box on the side of the engine, and then thru the existing harness up to your instrument panel.

I’ll assume you only have the basic panel ( or you would already have a temp gauge) and with the basic panel there will be no wiring in the panel for the gauge. You can go into the harness before the end connection and pull out the light brown wire, or install a pin and wire on the instrument panel side of the connector and run a wire from there to a gauge. No problem....

The thread on the sender, as I recall, is 18mm x 1.5 Which is standard VDO sender thread. You can buy a VDO sender and gauge for not too much, and they will more or less match your existing tach. Or you can use any other brand as well. Factory gauge went to 250* F.

The photo shows the sender location on a 2030 engine, and the 2020 is close to the same spot. The sender shown is the VDO which would fit that spot.

Hope this is helpful.

[basssears]

I would do both a coolant based gauge and a contact sensor. Coolant based gauges can misread if your coolant gets very low, so contact sensor is a good backup and a good contact sensor can also give you a warning alarm.


We added a second temp gauge to our engine (pilothouse, wanted gauges both places) and then added an Engine Watchdog with dual sensors, one attached to a bolt on the engine head and one strapped to the exhaust. The Engine Watchdog has alarms as well.


So now we watch our regular engine gauge carefully, but if we're busy or spacing out we still have alarm warnings if something starts to overheat due to low coolant or lack of raw water flow.


Some like it hot… (and other mods) – Sailing Idaho, the Salish Sea and beyond


-- Bass

[Kijit]

On our MD2040 I used foil tape and taped the sensor from a remote BBQ thermometer to the heat exchanger. I have the remote in the cockpit attached to the engine panel with Velcro. I now have a digital temp gauge and I can even set a custom alarm!

Gerhard

[Wotname]

Plenty of good answers already but if the OP wants simple and easy, then this is the by far the best approach IMO.

Originally Posted by basssears

......... then added an Engine Watchdog with dual sensors, one attached to a bolt on the engine head and one strapped to the exhaust. The Engine Watchdog has alarms as well.
............

[GarthGregory]

I am about to fit both an Oil pressure and Water Temp Gauge , both of which have to be SEEN to be effective . I also have a loud ALARM for both those functions , which has saved my engine twice over the years . The sender units are mounted in the block - Yanmar motor . I think the Alarm is first choice - gauges are nice to have .