Cooling temperature question Nortrac 254

[nt254]

I have a question about the cooling system on these tractors. I have a Nortrac 254. I replaced the stock thermostat with one that opens at 160 degrees F. I have a mechanical temp guage. I noticed while mowing that it will take a while to hit 160 (more quickly in hotter weather.) but the temp will slowly keep going up (170, 175 F). I then stop for a short time and the temp will quickly go down to around 160 F. I have an old John deere 2 cylinder gas engine. It quickly warms up to 160 and then the guage will stay around that. I am trying to figure out why the Nortrac goes past 160 and keeps going up. Why does the temp guage not show when the t-stat opens? What is an ideal temperature for these tractors?
I am not pushing the tractor hard. It only does this on hot days.

P.S. I keep the radiator clean from grass seeds, etc. I have even relocated the air induction for the air filter.
Any advise would be great.
Thanks,
NT254

 

[doxford jim]

I have a question about the cooling system on these tractors. I have a Nortrac 254. I replaced the stock thermostat with one that opens at 160 degrees F. I have a mechanical temp guage. I noticed while mowing that it will take a while to hit 160 (more quickly in hotter weather.) but the temp will slowly keep going up (170, 175 F). I then stop for a short time and the temp will quickly go down to around 160 F. I have an old John deere 2 cylinder gas engine. It quickly warms up to 160 and then the guage will stay around that. I am trying to figure out why the Nortrac goes past 160 and keeps going up. Why does the temp guage not show when the t-stat opens? What is an ideal temperature for these tractors?
I am not pushing the tractor hard. It only does this on hot days.

P.S. I keep the radiator clean from grass seeds, etc. I have even relocated the air induction for the air filter.
Any advise would be great.
Thanks,
NT254

It is possible that your mechanical temperature is out i.e that the increase in temperature shown, is not strictly linear. Do you have anything that you can check these readings with to verify one way or another, what the actual temperature is. There might not be anything wrong with the cooling system/engine and it might just be the gauge itself.

Just a thought,

Jim

 

[greg_g]

Well, you could have gotten a mismarked thermostat. That is, purchased a 160F box that had a 175F thermostat inside. Other than that, it sounds fairly normal to me. An automotive thermostat marked 160F is designed to start to open at 160F. But they open more slowly than they close. Coolant temp continues to rise as much as 20 degrees (F) as the thermostat is opening, but they close quickly upon sensing their close temp. See Automotive Systems .

The difference between the new gauge and the JD gauge is probably in the age of the movement. The JD gauge is quite likely just old and tired. Same could be said for the JD thermostat. Gotta admit though, I've never heard of a "mechanical" coolant temp gauge. Are you sure you have your terminology correct?

//greg//

 

[nt254]

Thanks for the replys. The gauge in the John Deere is a newer aftermarket gauge. I replaced it's t-stat a few years ago. When I say "mechanical" coolant temp gauge I mean that it is Not an electric unit. It has a metal line that runs from the gauge to the end that goes into the water port. It does not use electric current.

 

[RonMar]

Well as long as it stops climbing... I think the stock thermo is 80C which works out to 176F. When doing normal work my 284 steadies out just below 80C. When brushhogging, it will run in the low 80's. As the filter screen in front of the radiator gets clogged with flying debris, the temp starts to creep toward 90. I stop and clean the crap off the filter and it is right back to the low 80's.

 

[nt254]

A while back I asked about the correct cooling temperature for my nt 254. Today while changing implements I noticed the temperature gauge was around 180F. I was not even doing any work. The outside temp was about 88F. I have a 160F t-stat and I keep the radiator clean from dirt, etc. Should the temp. gauge drop when the t-stat opens to allow cooler fluid in the engine?? ( I replaced the stock gauge with a better unit) How can I check to be sure the water pump is working properly. How much pressure should the radiator cap have on these tractors?? Any advice would be great.

P.S. the coolant level in the radiator is never low so I do not think it is a head gasket issue.

 

[3RRL]

Well as long as it stops climbing... I think the stock thermo is 80C which works out to 176F. When doing normal work my 284 steadies out just below 80C. When brushhogging, it will run in the low 80's. As the filter screen in front of the radiator gets clogged with flying debris, the temp starts to creep toward 90. I stop and clean the crap off the filter and it is right back to the low 80's.

Yup,
That's exactly what I do and my tractor reacts the same way.

nt254,
Seems to me that 180°F is about perfect? Between 80°C to 85°C is pretty standard for most.

 

[nt254]

A while back I asked about the correct cooling temperature for my nt 254. Today while changing implements I noticed the temperature gauge was around 180F. I was not even doing any work. The outside temp was about 88F. I have a 160F t-stat and I keep the radiator clean from dirt, etc. Should the temp. gauge drop when the t-stat opens to allow cooler fluid in the engine?? ( I replaced the stock gauge with a better unit) How can I check to be sure the water pump is working properly. How much pressure should the radiator cap have on these tractors?? Any advice would be great.

P.S. the coolant level in the radiator is never low so I do not think it is a head gasket issue

Today I was running the tractor and I noticed the radiator was hot before the temperature gauge reached 130 degrees F. What could be causing the water to enter the radiator before the t-stat gets to 160 degrees? I noticed that the radiator cap was Not under pressure when I opened it. Also, should I change the 160 degree t-stat to a 180 degree F?

 

[greg_g]

Today I was running the tractor and I noticed the radiator was hot before the temperature gauge reached 130 degrees F. What could be causing the water to enter the radiator before the t-stat gets to 160 degrees? I noticed that the radiator cap was Not under pressure when I opened it. Also, should I change the 160 degree t-stat to a 180 degree F?

Some Jinmas were shipped with the wrong thermostats - 57C I think. Might be the case with your NorTrak too. Have you pulled the thermostat to see what temp is stamped on it?

Or do you know for a fact that yours is a 160? If so, 80C is the specified operating temp. That means a 180F would be the better choice.

//greg//

 

[nt254]

Yes, I put a 160F t-stat in the tractor. I am wondering if the water may be getting past the t-stat and going directly back in the radiator. I like to run the engine on the cool side because in the summer the outside temp is usually in the low to mid 90s. I do Not use it much in the winter. (My old john deere 430 runs good with a 160F t-stat) If the Nortrac runs better with a 180F t-stat I will probably change the one I put in.