running temperature

[Centurion]

Can anyone tell me what the normal operating temperature is for a 743 with 4 cylinder Kubota diesel? I installed a temp gauge, plus have the standard gauge, both in working order. When I am working the machine in 90 to 95 deg. temps, the engine coolant temp gets up to about 210 deg. The bobcat gauge still reads in the normal range. I have read a few things on hear that say over heating a 1702 is not good at all. I just want to be sure I don't cause myself problems. Any help would be appreciated.

 

[Tazza]

That sounds about rite. From memory the thermostats i have installed were marked 205 or 210F or i *think* 95C.
The temperature you are running sounds totally normal. If you are worried, grab a new sender and gauge, the sender is only like $7 and the gauge is around the $30 mark. You then will know for sure the temp is rite, i have done this myself just to be sure.
The heat issue is usually from when you blow a hose or run low on coolant, the thermal shock is what usually cracks the head when the cooler coolant goes over the hot section of the head and not from running a little warmer (a few degrees more). The problem isn't limited to just the V1702, the V2203 is the same, i think most water cooled Kubota's are susceptible.

 

[ThomasM]

Centurion, what letter in the word "NORMAL" on the temp gauge does the needle point at when it is 210 degrees F...? Just curious so I know on mine roughly. Seems like mine is around the "R" or "M" most of the time...The more I rev the engine the hotter it gets. I was looking in the service manual and my 743B shows no thermostat but the 742B part of the book does.

 

[73Eldo]

Centurion, what letter in the word "NORMAL" on the temp gauge does the needle point at when it is 210 degrees F...? Just curious so I know on mine roughly. Seems like mine is around the "R" or "M" most of the time...The more I rev the engine the hotter it gets. I was looking in the service manual and my 743B shows no thermostat but the 742B part of the book does.

210 should be plenty safe for a pressurized mixed coolant system. 15 psi and the proper mix should get the boiling point up over 250. Modern engines never run below 200, I think much of it is due to emissions trying to keep things more constant. Unless both senders are only an inch or so apart in the same stream its not a surprise they are reading different temps. A typical gauge runs 150-250 so 200 would be the middle. Those IR temp probes are getting fairly cheap and can be handy for all sorts of things. In a bobcat it may be difficult to get it pointed at many good places but it may still make you feel better by being able to verify temps in some areas.

 

[Centurion]

Centurion, what letter in the word "NORMAL" on the temp gauge does the needle point at when it is 210 degrees F...? Just curious so I know on mine roughly. Seems like mine is around the "R" or "M" most of the time...The more I rev the engine the hotter it gets. I was looking in the service manual and my 743B shows no thermostat but the 742B part of the book does.

at 210 degrees, the needle points in A L range, about 1/8" shy of the high temp mark. This from memory, once I get running (installing alternator, and had 4" rain last night) I will look at both and give you a more definate answer, as I have both temp gauges installed

 

[skidboy]

at 210 degrees, the needle points in A L range, about 1/8" shy of the high temp mark. This from memory, once I get running (installing alternator, and had 4" rain last night) I will look at both and give you a more definate answer, as I have both temp gauges installed

It was quite normal for older 743s to run between M --A ,this was due to a calibration problem between the gauge and sender. This was addressed by fitting a new gauge and sender.