Over heating issue

iamalienru wrote:
i changed the radiator because i picked up a bolt on the freeway that caused a small leak in it. i have changed the radiator cap. fan speed looks to be fine rotating at high revolution. i did notice that the site glass to the fluid tank had a slow leak from its O ring i replaced it now i just have to get warmed up and pull a grade with it because it won't get over 185 degrees just running it. when it heated up i was pulling with my boat so i may have to recreate the situation any grade would send the temp to unsafe heat level. As soon as i got off the grade temp goes right back down to 190 thank you for all of the information you all provided

all Diesel MH,s will run considerable hotter when loaded pulling a steep hill.Your,s getting to the boiling point indicates you may have a combustion leak(maybe) or your fan is not engaging when it should and not full force.There is a fan control switch right at the fan hydraulic drive unit.DISCONECT the wire harness.This will default your fan to high speed.Try it like that and see how the temp goes
believe me its certainly not as simple as a rad cap or anything silly like that

i changed the radiator because i picked up a bolt on the freeway that caused a small leak in it. i have changed the radiator cap. fan speed looks to be fine rotating at high revolution. i did notice that the site glass to the fluid tank had a slow leak from its O ring i replaced it now i just have to get warmed up and pull a grade with it because it won't get over 185 degrees just running it. when it heated up i was pulling with my boat so i may have to recreate the situation any grade would send the temp to unsafe heat level. As soon as i got off the grade temp goes right back down to 190 thank you for all of the information you all provided

iamalienru wrote:
I have a 1998 American Eagle has about 60 k miles on it. it over heats when climbing a sustained grade. I know it is heating because when it got hot it was boiling over. as soon as i get off the grade it cools down to normal operating temp of 190 and it does it pretty quick. I have a new radiator not more than 9 months old. it has a side radiator i can see the fan working. just can't figure it out. yes it has the proper fuilds that i top off before every trip If you have any ideas please let me know thanks

Have you cleaned or had it cleaned in a while. These radiators require periodic cleaning with a solution of some sort and a water hose and you might want to research the many existing threads concerning this.

We just had this with our Jeep (older). Replaced the radiator cap ($4.99) and the problem stopped. The old cap wasn't doing it's job anymore. Love these cheap fixes.

iamalienru wrote:
i thought about that but i just got done running it 600 miles you would have thought the air would have disapated in the system running it that long

Running it will not remove the air if it exists, If you have an air bubble you must purge the air from the system manually.

iamalienru wrote:
i top off before every trip

This sounds like you have a leak, maybe internal. How's the oil? In 10 years with 2 diesels I've never added coolant.

You said the radiator was fine before it was changed out. If it was fine then why did you change it?

Try a new cap. Does the engine have bleed lines to remove the air? I'd suspect the thermostat or the fan isn't turning fast enough. Maybe the fan thermostat or wiring? Probably a remote possibility that something happened to a vane on the water pump.

Do you have a hydraulic powered fan? Does it speed up when hot? Have you tried downshifting when it gets hot on the hills?
Bill

The radiator cap comes in different pressures. If it is sealing properly, the increased pressure will raise the boiling point of the coolant. For every pound of pressure with a radiator cap, the boiling point goes up 3 degrees. In other words, a 15 pound radiator cap will increase the boiling point 45 degrees.
A weak cap can allow coolant to blow out of the radiator when it reaches operating temperature and will not allow coolant from the overflow tank to be sucked back in. A weak cap also lowers the boiling point closer to 212 degrees which might explain the coolant boiling over sooner and explain why you have to add coolant before each trip. That is a cheap item to attempt to solve the problem.

iamalienru wrote:
it worked fine it is the exact same radiator that came out of it. the one thing i havent done is replace the cap could it be that minor of an issue?

Yes, a cap is critical.