Running Hot

[railroader]

I have a 350 Isc cummins engine. Had a new radiator put in and the temperature is around 225 deg. Before new radiator 180Deg. It starts to heat up as soon as I start down the road.

[rbturner]

I bought a Ford tractor one time that was sold to me because it had chronic overheating. It too had undergone a radiator replacement before I got it. I eventually found that when they replaced the radiator, they had neglected to remove a plastic cap/plug on the inlet that the manufacturer installed to keep dirt and crud out of it.

[MEXICOWANDERER]

ROW COUNT

TUBE COUNT ACROSS THE RADIATOR (Tubes closer together or further apart) Total Count

FIN COUNT PER INCH

A THREE ROW high tube count, high fin count radiator will cool ONE HUNDRED THIRTY PERCENT BETTER than a FOUR ROW low fin count, low tube count fraud.

[jwmII]

smkettner wrote:
Did you check the core rows were the same number?
Did all fan shrouds etc get properly reinstalled?
Did you verify coolant level?

You should not only have the same number of core rows but you also need the same number of cooling fins per sq. inch as the older radiator had.

[randallb]

My guess is that the antifreeze concentration is to high. Antifreeze does a great job of dumping heat and a poor job of absorbing it. When the concentration is to high insufficient heat is absorbed from the engine and when the coolant hits the new radiator it "dumps" what little it has absorbed. This effects the opening point of the thermostat, cooler upper hose and coolant, and if there is a fan clutch involved the cooler radiator causes the clutch to engage later. The result is a warmer running engine. If the engine has a fixed fan the heat is pulled out of the coolant even more and the engine runs even warmer. It could also be as simple as a failing thermostat if it was not replaced or an incorrect or faulty one if it was. As for the air pocket theory, if the coolant level is correct the system most likely has purged itself. If the level is low it definitely purged itself and needs to be topped off. All later engines have a purge hose that runs from the highest point in the cooling system to the surge tank. Earlier engines with a catch tank sometimes needed to be run with the cap loose to purge air.
Randy

[Mike_LeClair]

I would agree with the air pocket theory. Some of the Cummins motors have a bleeder valve somewhere close to the t-stat that you can crack open and then idle the motor until anti freeze comes out of the valve. Failing that you can as stated above drive a bit with the rad cap 1/2 tight although you have to watch it very carefully (somehow). I would take it back to the installer if that is at all feasible.

Cheers!

Mike

[robsouth]

What say the person that replaced the radiator?

[Jerrybo66]

mdamerell wrote:
Just a guess but it sounds like they put the wrong thermostat in.

Or defective... We all know where most aftermarket parts are made... 😞 Why did you replace the rad? Was it clogged? Would the new radiator allow more flow, resulting in a "vacuum" in the lower hose causing it to partially collapse, restricting flow ? Just a wild guess.. ("Been there, done that")..

[time2roll]

Did you check the core rows were the same number?
Did all fan shrouds etc get properly reinstalled?
Did you verify coolant level?

[mdamerell]

Just a guess but it sounds like they put the wrong thermostat in.

[powderman426]

My guess would be an air pocket.

Sometime it can be corrected by driving it with the radiator cap loosened to the first notch. This will keep it from building pressure and allow the air to be expelled.