Mf150 radiator spews

Had my new Massey Ferguson 150 out for the first time since December running around the field. As I was getting ready to park it after about 20 minutes of hard work climbing a couple of hills, I noticed the radiator was overflowing. Over the winter I drained the radiator flushed it with vinegar water refilled it put a new radiator cap on it. I have run it for 10 minutes or so at a time just to get it broken and it never overflowed.

I took the hose loose where I believe the thermostat should be. Just behind the radiator fan at the front of the engine. Nothing in there. I intend to get one but I thought no thermostat meant no over heating since coolant circulates freely.

Radiator fan ran the entire time. Somebody said that perhaps I filled it too full and it's just blowing off water to find it's happy place?

Without a thermostat the engine won't get to operating temperature, which means the engine won't run as efficient. It also may cause abnormal engine wear as parts are designed to run at certain temperatures.

How many hours have you ran / operated this Tractor since you purchased it?

When a machine has had the Thermostat removed, that can can indicate there was a cooling problem with this machine in the past?

Owners for some reason remove the thermostat....faulty or other wise and believe they have cured the cooling problem.

Once you have replaced the thermostat you may have to start eliminating the source of pressure building in the cooling system?....if indeed there is a problem?

Bob...

u said you drained it over winter and refilled it if u filled it to the top it will spit some water out because it expands when it gets hot. u might just have over filled it just as long as the core is covered it will be fine it don't have to be full to the cap

I only have ran it a couple of hours since draining and filling the radiator.

As I came back to the shed, the temperature started getting hotter and hotter. Started spewing and I parked it. It continued to spew until cool.

More diagnostics. I started it cold, let it run with no radiator cap. As mentioned previously, it has no thermostat.

Watched the water pump, hoses, and connections carefully. No leaks anywhere. Water pump turning, fan turning fine. Radiator fins are clear top to bottom and I can see clear through them.

Watching in the radiator, the coolant never seems to move. No bubbles.

After ten minutes, temperature gauge began to rise and coolant spews out of open radiator top.

I detected no bubbles in the mixture such as a failed head gasket. Once it started spewing, though, it was pretty much impossible to tell anything.

Why does it spew? If I filled it too full, wouldn't it eventually reach a comfortable level and quit spewing? I had drained, flushed with vinegar water, and filled in the last couple of months. I even drained the coolant out of the block.

Bad radiator? Lines blocked? Bad water pump?

This seems to be a one man conversation, but just in case someone runs into the same or similar problem--engine over heats--I'll share my results. I'm a newbie tractor owner, so I'm learning as I go.

As I understand it, the cooling system consists of:

1. Coolant
2. Radiator where hot water gets cooled off
3. Thermostat, which opens when water gets too hot from engine allowing coolant from radiator to flow through engine.
4. Radiator cap which keeps pressure in the system and will overflow when pressure gets too high.
5. Water pump which for the MF150 is driven by a belt from the engine, which also wraps around to drive the generator.
6. Hoses
7. Holes in the engine block where the real cooling work occurs. Coolant flows through the engine block and carries the heat to the radiator. This is where the infamous warped head can occur.

So, my quest was to determine which of these parts could be failing to cause overheating. I had installed a new temperature gauge, which was important since I could catch problems before they got out of hand. I'm told that overheating the engine can warp the head, which would be a major repair. I had also installed a new radiator cap and flushed the radiator with vinegar and water back in the winter. You have to use the correct pressure rating for your radiator cap.

I checked for obvious leaks in hoses, etc. Nothing.

Warped head or bad head gasket can cause overheating as coolant leaks from the tubes drilled in the engine block instead of returning to the radiator. Coolant can even leak into the engine oil. Two checks for this. First, take the cap off a cool radiator and watch for fizzy bubbles as the tractor runs. In my case, nothing. Second, look for "chocolate milk" in the oil. In my case, nothing. I checked both possibilities a couple of times. This was my most feared problem, but it seemed I was safe.

I checked the thermostat. Easy to reach. This tractor had none. Sometimes they get removed when engines overheat. People think this cures the problem, but I've read that the thermostat needs to be present to let the engine reach good warm temps thus operating more efficiently. It's a $10 part people! I bought a new one to install, but not just yet.

Hoses can collapse under pressure, etc. but watching the engine didn't show this problem.

Water pump could not be running which would mean the coolant doesn't circulate--just gets hotter in the engine block. I tucked this away in the back of my mind. The water pump on my MF150 is easy to reach, so I was willing to replace if needed. About $125 part.

BUT, before I did that I read that the radiator can get clogged. A way to determine is to take the lower hose off and let everything drain off. Then pour water in the top. If it runs out immediately from the lower hole, then water is circulating through. Seems easy enough and doesn't cost a dime. In my case, when I poured water in the top, nothing came out the lower hose hole. AHA! The radiator is blocked. So I look in the top of the radiator where I can see through the clean water to what looks like gunk covering some metal sheet. I got a screw driver and scraped/scrubbed. Hey, I uncovered some holes! and the water drained out the bottom hose hole!

So, I saved myself the water pump replacement and determined that it wasn't a warped head or bad head gasket.

Instead of vinegar, I bought some Blue Devil radiator cleaner to leave in a while and thoroughly flush the radiator. After that, I can reinstall the thermostat.

Yay, me!

With no evidence of coolant moving is a strange, and not very common problem. I would pull the water pump, and have a look at it. It's possible something could have happened to the impeller in the water pump.

DUH , I should have finished reading your entire post before replying, a clogged radiator would do it! With radiators these days radiator shops charge more to repair them than it costs to get new one. I would think a new radiator is in your future as chances are it was leaking, and they put all kinds of junky coolant leak sealers in it rather than fixing it properly, or replacing it.

Great job figuring it out.