L285 runs cold

MrPeabody

New member

Equipment
L285
Apr 17, 2017
13
1
3
Pleasant Plain
Hi all,

I bought an L285 a few years ago and I've been slowly working through some maintenance needs.

It has always run cold according to the temp gauge. Recently I had the radiator boiled out, replaced some bad looking hoses, and replaced the thermostat while I was there.

It runs the same temp now as it always has. The needle barely gets above the cold mark. Is this normal ?

I know it's getting fairly hot as the oil filter get so hot I can't keep my hand on it.

Here is a picture, that's as hot as it has ever been.

Thanks.

50172-24d0b44e3c040a0659ef3503d27f69db.JPG
 
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Henro

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Not familiar with your tractor. Does it have a water pump or is it thermo-syphon. Not sure if that is the right term for Kubota engines that use convection cooling.

Anyway, is there a thermostat that controls engine temperature? If the engine really is running cold perhaps the thermostat is stuck open.

Or maybe you have a problem with the temperature sensor and/or the temperature gage? Perhaps the engine is not running as cold as indicated.

Just a couple things to think about until someone more knowledgeable about your tractor chimes in...
 

Dave_eng

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Oct 6, 2012
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Understand that diesels inherently run cooler than a gas engine.

In a gas engine, the air flow is restricted at idle and until full throttle.

On a diesel, air flow is not restricted and this means a large volume of outside air is passing through the cylinders which, if the outside air is cold, cools the engine before the coolant enters the picture.

You need to get a real temperature measurement of your engine when warm. Infrared thermometers are cheap these days.

A cooking thermometer inserted into an open rad cap.

If you find the temp you measure is close to the thermostat you installed then you need to move to the gauge.

Remove the wire from the sensor and touch it to a good clean ground. The gauge should go to max,

50174-544120dd2d447ef03c3a22feada588e3.jpg



50175-4734b23269336a5d306fead5c05477d9.jpg

The sensor is a resistor whose resistance changes with temperature.

Unfortunately, with the older L series, available manuals do not provide an ohm value you could measure at differing temperatures.

If your physical check of the engine reveals high actual temperatures, if the grounding of the sensor wire causes the gauge to read its max, then by default the sensor could be replaced.

To answer questions by Henro, L175 are thermosyphon but higher model number L's of that era have water pumps.

Not all L's have water temp gauges but the L285 does.

Dave
 
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SidecarFlip

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Go to Harbor Freight and get yourself a 25 buck IR digital temp meter. I bet the gauge is off or the sending unit is past it's prime, or both.
 
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85Hokie

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Ditto what Flip said
 

MrPeabody

New member

Equipment
L285
Apr 17, 2017
13
1
3
Pleasant Plain
Ok, thanks for the advice. Unfortunately I'm pretty much done using it for the season, but I will get an IR thermometer and check the actual temps next time I run it.
 

85Hokie

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Ok, thanks for the advice. Unfortunately I'm pretty much done using it for the season, but I will get an IR thermometer and check the actual temps next time I run it.
Check at the neck of the top of the radiator and at thermostat housing.
If you do not see a temp close to 175 - 200 F - then (after a hard working of the engine) you need to find a way to limit air movement a bit. Diesels are cold running beasts - BUT a cool running engine is almost as bad as a hot running one. You want the machine to get up to temps - burn off all the moisture in the oil - a warm engine is much more efficient than a cold running one
 

MrPeabody

New member

Equipment
L285
Apr 17, 2017
13
1
3
Pleasant Plain
Hi, Just wanted to post an update.

I bought a IR thermometer as suggested (handy little device) and I can report that the engine is running around 180 degrees on a cool day not working too hard. So that seems normal to me.

Therefore, the sensor most likely needs replacing. However, now that I have a handy way to check the engine temp, and I know where on the gauge 180 degrees is, I doubt I'll spend the $60 Plus for a new sensor. Heck, my Ford 8N has been running for over 70 years w/o any temp gauge and it hasn't been a problem :)

Below is a shot of me taking the temp near the sensor at the rear of the engine.

Thanks for all the help !!
 

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85Hokie

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One thing to know on those - closer to source THE better the accuracy.

WHILE you are playing with it ..... lol ...... once hot, measure the lower neck of the radiator too.
If 180 F at top of NECK not the top of cap, then measure the bottom neck - I would think you will see 100-110 F or so...... lower is great - higher not so great!!!
 

SidecarFlip

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Hi, Just wanted to post an update.

I bought a IR thermometer as suggested (handy little device) and I can report that the engine is running around 180 degrees on a cool day not working too hard. So that seems normal to me.

Therefore, the sensor most likely needs replacing. However, now that I have a handy way to check the engine temp, and I know where on the gauge 180 degrees is, I doubt I'll spend the $60 Plus for a new sensor. Heck, my Ford 8N has been running for over 70 years w/o any temp gauge and it hasn't been a problem :)

Below is a shot of me taking the temp near the sensor at the rear of the engine.

Thanks for all the help !!
Looks JUST like the one I have................
 

Orange L285

Member

Equipment
L285 1200FEL
Jul 14, 2014
49
20
8
Texas
Hi all,

I bought an L285 a few years ago and I've been slowly working through some maintenance needs.

It has always run cold according to the temp gauge. Recently I had the radiator boiled out, replaced some bad looking hoses, and replaced the thermostat while I was there.

It runs the same temp now as it always has. The needle barely gets above the cold mark. Is this normal ?

I know it's getting fairly hot as the oil filter get so hot I can't keep my hand on it.

Here is a picture, that's as hot as it has ever been.

Thanks.

View attachment 50344
Good morning Mr Peabody,
I too have a early L285, 1975 model year I think. Always looking for insight on this tractor, look forward to seeing your maintenance projects posted.
FYI, I just finished a water pump and fan belt. Not too bad but I have a crankshaft mounted Hyd pump that made changing the the fan belt a little more difficult.