Radiator spits via overflow tube

Gregster613 · Jul 13, 2012

Hi guys,
I've got a question for all. I was moving some dirt yesterday [outside temps were warm but not excessively hot] it was dusty when loading & dumping bucket and after about the fourth haul I started smelling antifreeze sizzleing; I jump down - look - and yes the overflow spout was spitting out antifreeze? The tractor temp gauge was only in the middle - ie not overheating at all?? - I'm going what the heck is up with this?

I had checked the radiator screen before I even started up the tractor and it was clear & clean. I learned to to that shortly after I first owned & began operating this beast. I keep the screen clean and I usually also flush out the radiator with a slow stream of water from the hose after cleaning the screen. Except in the lower middle area that I just cannot get anything in to reach adequately. However, this is not the first time that it's spit out the overflow tube. So I wonder if I've got something going on that I need to check out??

Should I just add more antifreeze? Not worry that it does this strange thing? What more is there to check on? Anyone find a way to reach the lower middle area of the radiator with a water hose? Has anyone else with a 273 experienced this happening while radiator screen is clean? Need I worry? Has anyone replaced the stock radiator cap with an after-market? (I haven't, but am wondering if maybe the cap is suspect?) Open to sugestions, ideas on this weird issue.

Thanks, Greg

BobRip · Jul 13, 2012

Not familiar with your tractor, but I have a cap tester and have found that every cap I test after a year old reads low in the pressure release. You might have some trash in the cap which could be cleaned, but now I just replace them ever year.

BobRip · Jul 13, 2012

Check the belt driving the water pump.

Gregster613 · Jul 14, 2012

Well, it wasn't the radiator cap.
I just did my 250hr oil/filter change, changed out the cap with a new one fron Napa ($7.49), went and moved some more dirt [4 bucketfuls] - not even 45 minutes work - and it was spitting out the overflow tube again!

It must be the thermostat? The belt is tight, fan blades are good, water pump doesn't leak [like in an auto, when the water pump goes bad, it usually leaks] screen is clean, radiator is clean also. Soooo, I am going to let her cool down and then dissamble the thermostat and "hope" that that's it.

Fustrating that in only 250 hrs the thermo goes bad, but I guess that can happen. I'm curious tho, there are others who've owned this model TYM far longer than I have and I've yet to read about faulty thermostats?? Hasn't yet happened to anyone else? Strange! I'm well within warranty area yet but to find a dealer in an even remotely close range is next to impossible -- it'd take more time & $ to haul it anywhere than to just tear apart and replace what's needed.

I've gotten all my current tasks done so I'll not need be in a large hurry, but I don't like my "backsaver" to be unavailable at a moments notice! I'll try to repair as soon as possible and I'll be sure to report back with any news. Hopefully Good news!! Until satisifing results are at hand, Greg

flyerdan · Jul 14, 2012

I don't think you have an overheating problem, what's happening is that if you fill the radiator right to the top of the neck the coolant expands when at operating temperature and has to go somewhere. That's why all the newer rigs have the recovery bottle; it spits it out when hot and sucks it back when it cools off. If you can fasten a 1 liter soda bottle with a hole in the cap for the overflow tube there is a chance it will cycle, if it doesn't have the vented radiator cap.

Gregster613 · Jul 15, 2012

Hi Flyerdan,
You have a valid point I believe. However, I bought my TYM brand new and it didn't come with a recovery bottle. So I am unsure if it is supposed to be a cyclic recover system? I can add one, that's not hard..but is it actually the problem?
The service manual is rather vague in that regard. It explains about pressure testing of the cap, and lists the cap, thermostat, and water pump as suspects for overheat problems.

Yet, as I said, my temp gauge is only in the middle section of its range - just dashes, no actual numbers. So, according to the gauge it's not overheating?

But it is spitting out antifreeze! This tractor never gave these symptoms or problems until recently. The level has always been at the base of the filler neck when checked cold. It certainly is baffling.
Thanks for the input. Greg

boggen · Jul 15, 2012

on the old allis chalmers CA. i have. if i over fill the radiator. just a tiny bit. over top of the mesh down inside, i end up getting water/anti freeze coming out of the overflow tube. (as if things over heated)

if i do a wrong mix of antifreeze / water, and lower the boiling point. i will quickly get a boil over. causing the mix to come out of the overflow tube.

antifreeze / water mix tester are fairly cheap. there was a recent thread about using a regular multi meter you might use to check volts with. to also check antifreeze as well.

all antifreeze / water mix heat gauges i have seen normally have some sort of numbers on them. kinda like an odemeter in your car for how fast you are going. but may only show 0, 180, 210, 240 or something like that for how hot things are. with green to red sometime yellow in between them.

boggen · Jul 15, 2012

one last thing, make sure your "oil cooler radiator" for the hydrualics, and radiator for antifreeze / water mix themselves, are clean of debris and muck and like. to many times, i have had to let things cool down, and then take air compressor with blower nozzle attachment and blow everything out.

not knowing your tractor you may or may not have a hyd oil cooler on your tractor.

flyerdan · Jul 15, 2012

I think if it was overheating you'd know it, it would be venting steam and making sounds like an old percolator coffee pot. I'd rig up a recovery tank, fill the radiator to the top and leave the overflow tube submerged in about an inch of coolant in the tank. Mark the level for full cold and then see where it is after running it a bit, that will be the full hot mark. To ease your mind, you could get one of those IR thermometers from Harbor, they're not that expensive and are useful for other things as well. Then you can put a number to the gauge reading.