Hey Scotty,
I have a 2002 Dodge Ram 1500 5.9 magnum. It will not get up to operating temperature. It tops out about a quarter of the way up. Heat is barely Luke warm. I have tested the thermostat and it is working and is the correct temperature. Hoses all get hot. Doesn't appear to be air in the system. Fan clutch is fine as the fan will spin by hand. I'm out of ideas. Please help.
I'm out of ideas
Are you sure it's not a bad sending unit or the gauge itself? IDK if a bi-directional scanner would work on a 22 year old Ram maybe someone here will know??? Still, you can use a infrared digital thermometer to confirm the higher coolant temps flowing through that top radiator hose. The hose's reading won't match the actual engine's temp (~200°) but it will give you a good insight as to whether it's simply a 'reporting issue".
Cool heat could be a separate issue.
I'm working on getting a hold of a thermometer of some kind to check the coolant temperature. Once I get the results I will update.
So I noticed that the lower radiator hose is actually not getting hot. It's barely warm. Thinking I'm going to get a radiator flush to boil any crap out. Worst case, replacement radiator.
If the radiator was clogged the engine would be overheating. Coolant temperature should be checked at the upper radiator hose. (Or better yet, at the thermostat housing.) Coolant reaching the bottom hose has had its temperature lowered by the radiator.
So I noticed that the lower radiator hose is actually not getting hot. It's barely warm.
@drewklq hold up as believe you've got this backwards. The bottom hose isn't supposed to be 'hot'. The top hose should be 'hot'. Look again at the photo above posted by @chucktobias . Hot coolant returns from the hot engine through the top hose into the radiator. The radiator cools that coolant and returns it back to the engine through the bottom hose. Your bottom hose IS NOT hot which means your radiator is working.
Top hose is hot, bottom hose is cooled
@chucktobias hopefully he'll catch his error before wasting his time & money on a radiator that's working correctly. (Upvote)
If I did down vote, it was accidental. Still trying to get a hold of a temperature gun.
Stuff happens, not a prob. Those infrared thermometer guns are inexpensive & can be quite useful. You can pick up a new one for $20 (Amazon or Harbor Freight) or just borrow one.
Did you put the thermostat in upside down?
I knew I'd forget to mention something. Pretty sure it is correct orientation.
Measure your actual coolant temperature. It's possible the engine is actually reaching operating temperature but your 22-year-old heater core is clogged, or if there is a heater core shutoff valve that may be malfunctioning.
If you are certain that there is no air in the system, go ahead and replace the thermostat. A weak thermostat not closing as it should will cause the exact problem you are having. I know you tested it, but it is the most likely culprit. Good luck.
So I noticed that the lower radiator hose is actually not getting hot. It's barely warm.
this might suggest that the thermostat is opening before it is supposed to.
So I noticed that the lower radiator hose is actually not getting hot. It's barely warm. Thinking I'm going to get a radiator flush to boil any crap out. Worst case, replacement radiator.
So I noticed that the lower radiator hose is actually not getting hot. It's barely warm. Thinking I'm going to get a radiator flush to boil any crap out. Worst case, replacement radiator.
You've got it backwards. The top radiator hose is supposed to be hot, not the bottom. @Hixster and @chucktobias are right.
in a well functioning system , the top hose should be around 195F and bottom hose around 175F, which is still dang hot!
The car would overheat if the radiator were the problem though, or at least be running hotter than usual.
I still have dish hands from my time working at a restaurant. The rinse cycle was 180⁰F, the restaurant used cheap gloves and provided no insulation. There were huge mixing pans, and only one at a time could be run through the dish machine. I had to tell myself it's not hot while I'd move 45 feet to its location in the restaurant, haha.
It appears it may have been a weak thermostat. I remembered I had an extra and it's pretty easy to replace so I did and the operating temperature has come up. I don't think it's hitting the full 195 degrees but it's enough that the engine light turned off.
I am still working on getting a temperature gun. Thank you all.
It appears it may have been a weak thermostat. I remembered I had an extra and it's pretty easy to replace so I did and the operating temperature has come up. I don't think it's hitting the full 195 degrees but it's enough that the engine light turned off.
I am still working on getting a temperature gun. Thank you all.
Glad you got it fixed. Thanks for the update.
You can usually hear when the fan turns on at a lower temperature. If it does, it's probably the thermostat. And he fixed it.