Correct Temp for Mercruiser 1.7TD

Can anyone tell me what temp (on the guage) I should get when my Mercruiser 1.7TD is warmed up to normal running temp.

Thermostat starts to open @ 82C, fully open @ 95C. Block temperature should be within thermostat modulating range dependant on load. Anything over 104 C requires investigation.
 
I suggest that you buy one of those hand held temperature things which when you pull the trigger it sends a beam to whatever you are pointing it at and the display says what the temperature is of whatever the beam is pointing at.
The advantage is that if you write down the temperatures of what they are normally then you can tell if they are running above normal.
 
I suggest that you buy one of those hand held temperature things which when you pull the trigger it sends a beam to whatever you are pointing it at and the display says what the temperature is of whatever the beam is pointing at.
The advantage is that if you write down the temperatures of what they are normally then you can tell if they are running above normal.

the infrared thermometers are brilliant BUT should be careful where you point them at! Chrome and shinny metal shows much lower temps than it should!
Rubber pipes (black) are the best for temp readouts.
I often carry a felt pen with me and "paint" a shinny surface before I get the readout.
Obviously painted (or not) engine blocks are fine.

hope it helps
 
Mine run at 195 f. However, I plan to clean out the heat exchangers this winter when she comes out of the water.

Certainly good practice to regularly clean heat exchangers particularly with high specific output motor. Had to do a double take on the £'s Shillings and Pence, though I was the only one here who did not think Metric! Anyway I would be happy with 195 F / 92 C.
 
Certainly good practice to regularly clean heat exchangers particularly with high specific output motor. Had to do a double take on the £'s Shillings and Pence, though I was the only one here who did not think Metric! Anyway I would be happy with 195 F / 92 C.

Sorry LS, despite Rafiki being a UK built boat, she has temp gauges in £SD.
 
Sorry LS, despite Rafiki being a UK built boat, she has temp gauges in £SD.

One of pains about Mercruiser stuff, U.S. is still perceived as centre (note the spelling) of the Universe.

I wonder how many folks have their SmartCraft instruments set to read consumption in gallons instead of liters without realising that they are reading in small US Gallons. Spoke to a salesman who was extolling vertues of SmartCraft, when I mentioned that he needed to multiply by 1.20094 he looked a little blank, he then asked if boat test journalists understood. Boat had been tested with same sales guy on board system set up in gallons, nobody mentioned that test figures were in baby gallons........

Same applies to the CAT monitoring system, I always tell owners to set up systems in liters as U.S. Gallons can confuse the hell out of people.
 
One of pains about Mercruiser stuff, U.S. is still perceived as centre (note the spelling) of the Universe.

I wonder how many folks have their SmartCraft instruments set to read consumption in gallons instead of liters without realising that they are reading in small US Gallons. Spoke to a salesman who was extolling vertues of SmartCraft, when I mentioned that he needed to multiply by 1.20094 he looked a little blank, he then asked if boat test journalists understood. Boat had been tested with same sales guy on board system set up in gallons, nobody mentioned that test figures were in baby gallons........

Same applies to the CAT monitoring system, I always tell owners to set up systems in liters as U.S. Gallons can confuse the hell out of people.

I'm old enough to just about remember that water boils at 212F as well as 100C (or a bit more in a pressurised system). Actually, when I was at Land Rover, our gasoline engines boiled at 127C, and normal temp was 110C. Was a bit worrying having cut my teeth at Jag, where anything over 95C was getting twitchy.
 
I'm old enough to just about remember that water boils at 212F as well as 100C (or a bit more in a pressurised system). Actually, when I was at Land Rover, our gasoline engines boiled at 127C, and normal temp was 110C. Was a bit worrying having cut my teeth at Jag, where anything over 95C was getting twitchy.

my 90s vintage Fiat 2.0lt 16v turbo engined coupe runs at 98-111C, fans kick in at 108C. Heavily pushed to 330bhp and keeps running even at Greek temps (well wont push it throughout July and August with 36+C....)

Doesn't mean I'm happy with that, I'm much prefer if it run at 90-95 especially with high ambient temps.

EGT and wideband lamda sensors are the only safe way of knowing what your engine is doing, but not seen them used much in marine environments.

V.
 
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my 90s vintage Fiat 2.0lt 16v turbo engined coupe runs at 98-111C, fans kick in at 108C. Heavily pushed to 330bhp and keeps running even at Greek temps (well wont push it throughout July and August with 36+C....)

Doesn't mean I'm happy with that, I'm much prefer if it run at 90-95 especially with high ambient temps.

EGT and wideband lamda sensors are the only safe way of knowing what your engine is doing, but not seen them used much in marine environments.

V.

Old quote but petrol (gasoline) is for poofs, absolutely zero point comparing one engine with another. Running temperatures have increased higher top tank temperatures, by use of higher pressure rad caps.

EGT absolutely, and common in marine enviornment. lambda sensors in engines which do not operate stoichiometric (Diesel cycle as opposed to Otto cycle) pointless! However suddenly we are discussing combustion temperatures at same time as coolant temperatures, simply nuts.
 
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