Cooling water temp. measurement and possible engine shutdown.

[cb750k8]

Hi All
I am indebted to Alexisferos in his submission on cooling system tests done on a B7100. (address below)


My tractor B7200 was loosing water and it turned out the fan belt was touching and eroding a hose and spreading the water and I could not find the leak. When doing something else I noticed the damaged hose.

This got me thinking about how vulnerable these old engines are with no temp. supervision and there are a few bad stories on this and other sites about meltdowns when water runs out or the radiator is blocked and cooling fails. I understand that on later models the horn blows if water temp. exceeded set levels.

So I purchased a digital thermometer (ebay or alibaba) for all of 5 dollars. It was shipped from China to Dublin and took about one month.

These things are available at trivial prices but you need to look at voltages, ingress protection IP rating, mounting and probe location.

I installed the 3mm stainless steel probe (thermocouple) at the plug no 140 shown and located the LED temporarily on the bonnet near the steering wheel. See Photo. 12 volt power supply was taken from the Key Switch.

The system works well and for 5 bucks it is probably a good investment, however, I intend to improve the system by purchasing a digital thermostat with relay which can be set to close contacts at preset temp. This can be used to blow the horn. A 12v unit is on order (China for about 10 dollars and after Christmas)

More modern tractors (and cars) have automatic shutdown if temps. are exceeded and there may be a solenoid shutdown on more modern D950 engines. If anyone is aware of a shutdown solenoid for this engine I am interested.

I will report on installation of the latest Mark 2 10 dollar upgrade!!













http://www.orangetractortalks.com/forums/showthread.php?t=16639&highlight=thermosyphon




http://www.ebay.co.uk/itm/12V-Vehic..._Measurement_Equipment_ET&hash=item3ce4c6c17f

 

[North Idaho Wolfman]

The B1750 had the parts needed to make it a solenoid controlled shut down.
It wouldn't be cheap, solenoid is around $100 and relay around $65 not including all the linkages and new stop plate.
I have that setup on my B7100 with a D950 upgrade but it was out of a Jacobson lawn mower and already had all the needed parts.

 

[ShaunRH]

Considering my near meltdown on my 2013 L3200, I think this is something that I need to incorporate into my system (auto shutdown) but I think I might make it fluid level based and not temp based.

I have the temp gauge but still nearly boiled all the fluid out of the external fill tank. I think the boiling effect keeps the unit from overheating dramatically (it's what notified me of a problem, it does whistle a bit like a tea kettle - at least I know the sound should trigger a glance at the temp gauge and you can smell the anti-freeze too) but as a final "What? Still not looking at your temp gauge idiot?!" thing, maybe a fluid level float added to the tank that triggers the solenoid fuel off function. This would also serve as a 'do not start' safety if you haven't got fluid in your overflow tank.

Not sure if it's a good idea or bad but even these new tractors don't have all the safeties they should on the coolant side.

 

[brmax]

That's a great idea and digital, On my generator here a Kubota 4cyl it has the thermostat base resembling your above inset picture. A factory hi temp thermo switch it has in the 140 #, I cannot make out a part number but im sure it goes to high for my liking.
Anyway it is wired to dis connect the "hold in" wire on the injection pump fuel solenoid. On this motor I have its not a computer operated system, I would be interested in thermo switches of different temp openings also.

great post, and thanks to ya there
good day

 

[Alexisferos]

nice and cheap add to the tractor.
well my opinion about the meltdowns and the other temperature problems that have reported is that the human operator is responsible for everything.
you see if you don't clean the radiator, you don't check the fluids, etc then the tractor is gonna leave you one day.

as for the emergency auto-shutdown in older tractors like mine is little difficult and expensive to be done,
now everything electrically driven or shut off, it can be done with just a simple installation of a temp gauge with warning light and some relays.

cb750k8 look plz at this temp gauges with the warning light, the cheap ones are not more expensive from your 10$ gauge and the expensive ones they adjust and the temp warning light.

18$ gauge with red light and 212f

70$ gauge with settings

you can connect the red light signal with a relay and just make your tractor do what you want, play the horn , open lights, even if has electrically shut off from a switch shut it off.

 

[ShaunRH]

...
well my opinion about the meltdowns and the other temperature problems that have reported is that the human operator is responsible for everything.
you see if you don't clean the radiator, you don't check the fluids, etc then the tractor is gonna leave you one day.
...

While it is ultimately the responsibility of the operator, conditions do arise very rapidly that an operator paying attention to their implements, terrain, or whatever, doesn't get eyes back on the temp gauge often enough to catch it. You might want to read this thread:

http://www.orangetractortalks.com/forums/showthread.php?t=16747

There is not much overhead temp room on some of the newer L series units and you can go from 'normal' to 'overheat' in the blink of an eye even doing everything properly.

Automatic shutdown would be nice in these conditions, so it's not just the older units that can suffer the problem.

 

[brmax]

Fwiw I don't think I want a tractor that's going to shut down automaticly, but I would totally agree to have some blinking lights as most have had since the 90s. This conversation is forcing me to check the temp switch opening degree, again its on a gen but just to much going on for me to let a tractor shut down without certain warnings in a series. Even in my faults I would prefer to get to a certain area of the field or such.
Someone could use the same setup to switch a cube relay operating a flasher setup.
Good day