640D cold blooded!!!

[cutter88]

Since I bought my 640 a year ago I noticed the heat gauge never worked, assumed it was broke so I put a compete new system in gauge, sensor and water line between them... Started working in hot temps this week and the gauge never moved,,, it starts at 130 degrees is it possible that the engine is not getting that work? Is that Normal or should I be looking for a problem?

[Brleclaire]

You could run the machine till you figure it should at operating temp then very carefully take off the radiator cap and put a meat thermometer in the coolant and see what the temp is this will verify if the gauge is not working. If temp of coolant is cold I would think your thermostat is stuck open if coolant is between 170-180 F then you know your gauge isn't working. It's not good to run a engine cold all the time you get a lot of sludge and soot build up.

[dnash]

I have the exact same problem. I can get it up to about 140 but not much more. I've often wondered whether or not there is an air pocket around the temp sender unit (mechanical gauge) causing a faulty reading. I don't figure this is normal. Once we are done the next woodlot, I've got a bunch of maintenance etc. to do so hopefully I can tackle it then.

[cutter88]

Ok ill check it in the rad with a probe first if she's cold ill tackle the thermostat

[HiTech]

maybe you should check to see if it has a thermostat in it.

[36 coupe]

Since I bought my 640 a year ago I noticed the heat gauge never worked, assumed it was broke so I put a compete new system in gauge, sensor and water line between them... Started working in hot temps this week and the gauge never moved,,, it starts at 130 degrees is it possible that the engine is not getting that work? Is that Normal or should I be looking for a problem?

That ls not a water line.The sensor has ether in it.Ether expands when heated so your temperature gauge is actually a pressure gauge.Ill bet Bubba took the thermostat out thinking it would stop heating.Thermostats can be tested for opening temperature in a tuna can on the stove with a meat thermometer.Dont boil ,just watch the temperature rise to see the opening  temp and the full open temp.Thermostats  can stick open or shut.You dont have to open a hot pressure system to check the temp with a meat thermometer.Just take the cap off before starting the engine.

[cutter88]

I picked a set of stats up and a housing gasket yesterday ill take that on satetday also have a new tranny temp sensor and gauge to install