Still getting hot

[jamesh]

Thanks to all who helped last time I posted about my Case 850D getting hot.I thought I had the problem licked after burping the air out of the system.It ran cool for exactly 1 day before getting hot again.It has new(used)engine,new thermostat,new belt,refurbished radiator,and hoses all look good.What am I missing?
 

[WayneB]

What blend of coolant?

With some of the military equipment I worked on, we experienced overheating if the coolant had pure antifreeze

Second: Have you pressure tested the cap and coolant system?

for every pound of pressure created in the cooling system, the boiling point of the water is raised by three degrees. A 15 PSI cap boils at 257 deg versus 212, etc. This does not factor the benifit of glycol, nor the detriment of pure or too much glycol

Are there bubbles forming in radiator? Does it push coolant out (when cool) running?
 

[Dennis K (WA)]

A couple things come to mind.
Is your fan shroud in place? If it is not you will heat. Rule of thumb is 2/3 of the fan should be inside the shroud.
Is your fan on backward, if it is not a reversable type? If it is it will heat.
I didn't think the 621 and 850D had the same engine but I could be wrong.. Are they compatable? RPM and HP
Good luck
Dennis
 

[AJ.]

The 621 wheel loader and the 850D share the same engine a Cummins 6.590, as mentioned the fan shroud is an important as is the correct spacer between the fan and carrier,remove the thermostat and use the machine without it and see how it goes,if its still getting hot check the coolant for air bubbles,this is best done when it is hot,slacken off the fan belt so the water pump and fan will stay still, fill the rad to the top,start the engine and keep it at 800/900 rpm,watch the coolant for at least a few minutes,if you see air bubbles coming through it that indicates compression is leaking into the cooling system.could be head gasket,cracked head or cracked cylinder,if there is no air bubbles you can eliminate those things,had both the engines turbos on them,the pump settings would be different for a turbo and none turbo,is the transmission temperature staying in range.
Good luck
AJ
 

[jamesh]

Still gets hot even after checking shroud,coolant,and for air bubbles.Engine will stay cool when in neutral but once you put it in gear and start working it gets hot in a hurry.
 

[AJ.]

Do you know the history of the engine,was it ok in the shovel,was your old engine overheating,the problem is you have an engine that is ok when the machine is in neutral but starts to heat as soon as you work it,so either the cooling system is not man enough to keep it cool under load or there is a mechanical reason,thermostat not opening enough,water flow through the rad too slow,rad not cooling the coolant enough,is the fan blowing enough,a heat gun can save a lot of hassle by taking a reading from the top and bottom of the rad,there should be a noticeable difference between the two even by touch if you don't have a gun.
Good luck
AJ