Ford 4000 3 cyl Diesel Running Hot

3 cyl diesel running hot according to the gauge. I replaced the sender and that made no difference. Gauge starts out cold and as the tractor warms up it slowly goes to all the way to
super hot. I ran the tractor for 15 minutes and held my breath. It is not boiling and when I shut it off I was able to remove the radiator cap. Where was a little pressure but it was
not boiling. Started it back up and it seems to be circulating. Although, when I squeezed the top hose I could not feel water moving in it. Top of radiator is hot and the bottom is
noticeably cooler. Tractor is running fine and doesn't appear to be running hot. Water pump is turning freely and is not making noise or leaking.

I would replace the thermostat but I don't see how, without removing the radiator. Is that the best way to get to the water pump and thermostat. It was a chore just changing the
sender.

If I can find a candy thermometer I am going to check the oil temperature. What should it be if the engine is running/cooling properly? Is there something else I can do to check the
block temperature? If I opened the block drain by the starter, there should be water purging out of it while running. If there is no water draining, that would mean the block had
boiled dry. I just hate to look at that gauge and not know it the tractor is really hot or not.

Give us some history... is this tractor new to you and it was showing hot on the gauge after running some since you got it, or have you had it a while and this is a relatively new symptom?

First off.. is it hot or not... get a infared heat gun and shoot the themostat housing and check the temp there. It will show the engine temp. Shoot head in rear of head , middle, and front, on side away from exhaust manifold. see what is really happening. Determine if the gauge is correct or not. If this show engine below 200, typically 150 to 190, your gauge is wrong.


Usually I can see some water circulation. I would pull the thermostat and put it in a pan of water on the stove and and check its opening temperature if not able to verify temp.

Or run the tractor with out the thermostat to check whats happening. top of radiator should show around 160 to 190. Bottom should drop considerably 40 degree or so. top temp will be nearly the temp at the thermostat housing if the water is circulating properly.

You may simply have a bad temp gauge or a bad voltage stabilizer, or wrong sending unit for the gauge your using. There were 3 different sending units [b:6ed719dfb4]if I remember correctly[/b:6ed719dfb4][/u] to go with 3 different gauge units. Row crops had their own sending units. Some sending units were bigger for the older gauges again IIRC. So someone could have the wrong gauges on the tractor, a newer head on the tractor, or a host of other things like wrong wire to wrong place.


Fill radiator to very very top..while running... look for bubbles,, if it bubbles constantly you have a problem that will cause overheating,,, ie blown head gasket, cracked head or pin hole.

Good luck and let us know what you find.

Here is more of the story http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ford&th=597703 it is on page 4 . when I took the proof meter out there was a piece of rubber gasket near the needle, I didn't think it interfered with the needle but may have. After putting the proof meter back in the temp. gauge went to hot hot. Have had the tractor for 2 years and no heating problem, until I worked it too hard and let the radiator fill up with chaff and it did boil. I am thinking I cooked the thermostat. Can I get to the thermostat housing by taking the entire hood off or is it easier to just take the radiator off? Where do I find an infared heat gun?

http://www.walmart.com/c/kp/infrared-thermometers

walmart order section for about 17 bucks.eBAY HAS them for 9 to 16 bucks.

harbour freight, sears, walmart, ebay, etc...


I have serveral, for a/c work and lots of other chores... Keep on in the pull truck for checking tires and axles.

OK, so I got a infared Temperature gun coming. Back to my question about the thermostat, Do I have to take the radiator off to get to the thermostat housing? Or can I get to it by just removing the entire hood? I had a heck of a time replacing just the sender!

Lifting the hood is sufficient to get to the thermostat housing.... but I would leave that alone for the time being. I don't know why you're so worried about that.
You most likely have a problem with the guage.
When you get the IR gun, take the temp readings on the right side of the engine block just under the head. I find that to be the truest readings on these engines.

Rod

I have the same problem. Sometimes I just slap the gauge around a little and the needle falls back to where it belongs. I'm guessing it has to do with the voltage conditioner being old or maybe some kind of ground fault. I occasionally check the radiator temp with an IR thermometer to be sure.

It's just one of the many things I live with in a 50 year old tractor.