L35 Unusual Engine Temps

[SLOBuds]

I have a year 2000 L35 with 1025 hours. Bought it used and been very pleased with its performance.

The tractor was showing low engine temperature which I verified by using a temperature gauge - it was 135 at warm idle. About 50 degrees off. The tractor would keep at this temperature seemingly forever. Bought new thermostat but did not install yet.

Last 2 days I've been brush hogging my 10 acre parcel. It's a hilly site, so the tractor's been worked pretty hard going up and down hills, towing a brush hog. Lots of shifting, changing direction, up and down with the 3ph, etc.

After running a few hours, the engine temperature started to ease up towards the red mark. When the needle was close to redmark, I shut it down.

Took lunch for 30 minutes. Got back in, started up, needle was low again. Not cold-morning low, but about 1/4 off bottom mark. Then started creeping back up again.

Outside temperature is high-60's. Oil topped. Radiator topped. Radiator screen clear of debris. No funny sounds anywhere. No leaking fluids. Everything looks good except engine temperature.

I really would not expect an overheat on this tractor after 2-3 hours of work. Especially when the engine typically runs too cool from the malfunctioning thermostat.

Any ideas?

 

[hutch4472]

I also have a 2000 L35. I cant get the needle to move past 1/4 hot. Even in our 105* August days while working it hard. Were you lugging the motor at all? I would think either dirty radiator fins (you said that looked ok), thermostat sticking, water pump going, or radiator needs to be boiled clean or replaced do to internal clog. Also did the motor seem hot as in radiating alot of heat so as to eliminate a fault temp gauge?

Hutch

 

[SLOBuds]

Did you ever try another thermostat for yours?

I pulled off the front cowling and noticed an hydrolic fluid radiator - small one, to the left of the battery - and it was about 1/3rd clogged with dirt. But I would not think that such small area would cause the over-heat. I cleaned it anyway.

The brush hogging was not gentle on the tractor. My parcel is full of hills that aren't even themselves. Frequently the mower would gouge into the ground, which caused the engine to lug.

I do think that the thermostat is stuck - but stuck open, giving me a cold-run engine.

Maybe that was it.

I checked my engine temperature with a gauge, twice. Spec for our engine is 185, if I recall correctly. It's not good for the engine to run cold for long periods of time. So I'm going to try the new thermostat. Maybe that could be part of the overheat problem too, but not sure how.

Thanks for the other tips.

 

[Wombat125]

When the needle was close to redmark, I shut it down.

I'm certainly not a dieselologist, but I think in this situation I would be inclined to take all load off the tractor and run her at idle speed for a few minutes to keep the fluids circulating and to see if the temp needle starts nudging in the right direction.

The small diesel manufacturers that I've dealt with frown on shutting down a hot worked motor without a little cool down time.

I'd hate to see you put unnecessary wear on your tractor, although your problem is strange enough, that we're not even sure that idling back would cool her down.

 

[ray66v]

The small diesel manufacturers that I've dealt with frown on shutting down a hot worked motor without a little cool down time.

Amen, I would not sleep well if I had to shut it down in the red. Can you lightly spray the radiator with a garden hose and get the temp. down first next time?

Have you had to replace missing antifreeze recently?

 

[blagg]

Thermostats can stick through out their operating range. They can stick open partially causing temp to not come up, then cycle and not open but very little and overheat. One third of the surface area of your fins plugged can cause overheating. The manufacturer designs enough radiator capacity to cool the engine at full load all day long. They dont give you much extra! Change the thermostat and clean out radiator and hyd cooler fins very well. Should take care of your problem.

 

[SLOBuds]

I'm certainly not a dieselologist, but I think in this situation I would be inclined to take all load off the tractor and run her at idle speed for a few minutes to keep the fluids circulating and to see if the temp needle starts nudging in the right direction.

The small diesel manufacturers that I've dealt with frown on shutting down a hot worked motor without a little cool down time.

I did that but not long enough to my satisfaction. The engine was actually stopped left of red, but after a short idle-at-rest and then shutdown I heard boiling in the radiator. Just let it go but didn't feel all that comfortable. No odd noises on restart, and temp was running back down in the low zone again as mentioned.

OK, I'm thinkng it is the thermostat and maybe the partial block of hydraulic cooler fins. Plus I didn't mention before another 10% blockage on the front grill itself. Cleaned the cooler and grill yesterday and will post update today or tomorrow. The heavy work is done though. So work conditions are not as hard on the machine.

The water radiator has a nice screen in front of it to catch dust. The hydraulic cooler doesn't. I'm thinking about rigging something for in front of it similar to the screen. Maybe something like one of those black fibre screens that are used over ranges and window air conditioners. Put that in front of the grill somehow. The L35 is designed pretty nicely in that respect. The grill has large screening on it, the water radiator has fine screening in front that is easy to clean. The hydraulic cooler is not protected though.

Thanks againfor the tips.

 

[john_bud]

My L3410 has the same engine as your L35. It has always run at the bottom of the temp range when idle. It will only get past the 1/4 range when the screens get clogged up. There are 3 on the tractor (may be different on L35). The grill is full of small holes and that stops lots of leafy seedy stuff. Then the hydraulic cooler has a screen then the radiator has a screen. After a day of hogging, I blow the radiators out with compressed air and always get huge clouds of dust. Every 3-5 blow outs, it gets a hose out and there is still dirt coming out then too.

I would wonder about the water pump if the radiators are clean and the new thermostat fails to fix.

jb

 

[SLOBuds]

My L3410 has the same engine as your L35. It has always run at the bottom of the temp range when idle. It will only get past the 1/4 range when the screens get clogged up. There are 3 on the tractor (may be different on L35). The grill is full of small holes and that stops lots of leafy seedy stuff. Then the hydraulic cooler has a screen then the radiator has a screen. After a day of hogging, I blow the radiators out with compressed air and always get huge clouds of dust. Every 3-5 blow outs, it gets a hose out and there is still dirt coming out then too.

I would wonder about the water pump if the radiators are clean and the new thermostat fails to fix.

jb

Same exactly as my year-2000 L35 except for the screen in front of the hydraulic cooler. Missing. I'm going to try to find a picture of your 3410 setup and maybe fabricate the same thing.

I tested the temperature by infrared thermometer on the thermostat housing, a few hoses, and a couple other places. Showed around 110 degrees. Spec I believe is 180 or 185. It kind of bothers me that a couple of us are reporting low operating temperatures. It is not good for the engine to run below its design spec.

Yesterday and today after my clean-out the engine was showing it's same low temperature. No run-ups. It is also interesting to me that 1/3rd blockage of the hydraulic cooler, and 20% blockage of the front grill 'small holes' would cause an overheat.

But we'll just fix one thing at a time and go from there. Thermostat first.

Thanks.

 

[john_bud]

Next time I pull out the tractor (forcast is for 5 -7 days of rain ) I'll try and remember to snap a picture.

From memory, the hydraulic screen has 2 brass eyelets and hangs from hooks, unlike the rad screen that slides into a groove. Then again, it's from memory!

On the temps, diesels do idle cool. Much lower than gas engines. I probably should zap mine with the IR stat and see what it is at idle....

jb