So a couple weeks ago driving down the highway, Ultragauge temp warning went off truck got hot trying to get off the road. Once off the road noticed coolant spraying out of the overflow tank. Found the bottom radiator hose was significantly cooler than top hoses and figured thermostat failed.

Got the truck towed home called Lucky 8 and got a new 180 thermostat installed. Tried my best to bleed the system but keep getting the waterfall effect and the system is over pressurized. Now I have never had issues bleeding this truck.

Kept looking for issues and found that the bottom radiator hose looked kinked, so called Lucky8 and ordered new hoses and filled the system up. At this point can still hear air in the system even after bleeding for multiple days. Bottom radiator hose gets warm but still significantly cooler than the top hoses and system is still over pressurized.

At this point I assume that the initial issue may have cooked the gaskets. Figure this could also be the reason for air/gas getting into the system. Ran four separate gas test on the cooling system and they all passed. Heater core hoses are both same temp.

My question and the only thing that has stayed the same is the cooler bottom hose. So my question is can a clogged radiator cause the system to be over pressurized and because it may not be cycling the coolant allowing same amounts of air back into the system?

 

Have you used a pressure gauge to verify over pressure? Have you replaced the reservoir cap and inspected reservoir closely for leaks? Ativan and Prosac may work too.
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Replaced thermostat, cap, and hoses at this point. Both caps were allowing coolant to pass from the reservoir overflow tube after a short 1 mile drive. The truck idles all day perfectly fine, once you start moving the temps start to climb though. With what I have done it takes a little longer to get to 210 and pull over.

The other thing that makes me think it could be a clogged radiator is it will not overheat at higher RPM's just lets coolant out the overflow.

 

Once moving the engine produces more power/heat. Water pump might not be circulating enough coolant if impeller eaten up, slipping on shaft or system restricted. Cooler lwr rad hose may indicate good rad?

Doing armchair troubleshooting I'd think about a new water pump and a good flush cleanse of your rad & cooling system to start. Pulling block drain plugs while doing a drain/flush/cleanse might be wothwhile if you're man enough.
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Yeah, I'd go with the route suggested by number9. At this point, I'd do a complete rebuild of the cooling system. At 210F you're still okay--should not have any issues with the head gasket.

- Replace all rubber hoses, at 134K they need to be changed anyway
- Take out the radiator for an inspection, cleansing, and potential replacment
- Replace the water pump
- Flush, flush, flush!

When it comes to older vehicles, I pursue the "while I am there..." methodology. Typically, when a single part of the system fails, it may make sense to re-do the whole thing.

 

When you reach 210, does it go pass that temperature? Does it go down when not on highway speed?

 

The coolant system was all replaced 3 years ago. It will go above 210 driving unless the revs are kept higher than 2k.

The water pump not working would not result in over pressurization.

 

Stupid question but are you blasting the heater to maximum for every bleed procedure?

 

Doesn't make any difference. The heater core passage ways are open either way on these trucks.

 

I never knew that.. Good to know.