John Deere M overheating

RHV

New User
I have a 1949 John Deere M that runs hot.
I"ve flushed the cooling system out and replaced the temp gauge. The rad is in good shape,nice and clean, and have 50% antifreeze mix. The temperature goes well above 200 and a bit of coolant usually leaks out the overflow tube.
I"ve checked the timing and it"s right on.
Any ideas? Thanks.
 
I will assume you don't have a rad thermometer ? This temp reading is not unusual, mainly because of the location of the sensor. I'd suggest you take out a quart so it doesn't overflow and let it idle with the rad cap off. If it doesn't boil and spit out a bunch more water, it will be ok. Mine (and most others) reads high on the gauge, but it never boils. Keep us posted - RonMC
Tractors and Mexico
 
As long as you premixed the antifreeze and the muffler isn't stopped up you have nothing to worry about.

The temp guage on an M is pert near useless. Pay it no attention unless there's a reading that isn't normal for your tractor. Late models moved the sending unit location because of inaccurate readings, but they still weren't very accurate.

My M runs around 210 puttering around and 225 when she's working hard.
 
These are thermo syphon systems meaning there is no mechnical pump to circulate the water.
They will not cool properly if they are either under filled nor OVERFILLED. The fact that you have antifreeze coming out of the overflow says that you may have it too full and/or may have a bad rad cap.
The water needs room to "waterfall" out of the return line at the top of the rad in order to work.
 
Agree with the others that the temperatures run high; temps run over 200<sup>o</sup>+ on our 51M and both our 51MTs.

Got Nancy's cooking thermometer and checked temperatures one day; thermometer read lower than the gauge.
 
Looks like I had the rad too full. I removed some coolant leaving 3 gallons in the system. It still shows hot but it doesn't boil.
Thankyou to everyone who responded to my query. RHV.
 
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