Could a failing expansion cap be the cause of my overheating?

 

or a cracked tank that only leaks when car is turned off hot and builds up pressure,next time you run it til it gets hot turn it off and lift hood and watch where it's leaking from,if it's the cap change it or tank,sometimes the top rad hose will collapse and is also a sign of cap not venting properly,let us know

 

btw,you say this occurs when your truck is at 200 degrees,that's not overheating,sounds like a pressurization problem which can be blockage or above mentioned type conditions

 

Yes the viscous fan is spinning.
I have lifted the hood and have seen coolant coming from the overflow cap.
Maybe time to do a radiator flush with the garden hose.

Thanks!

 

i'll leave it here,if your draining rad mine as well take out t-stat and flush engine as well and reverse flush heater core,good luck

 

There's no mistaking the sound of the viscous fan when its enaged.

 

Nice video!
The viscous fan is working.

Does this mean to drain the coolant and replace with water with t-stat removed?
What is the process for reverse flush heater core?

Thanks!

 

My similar experiences...

1. A slow gradual increase in temp from a typical running temp of the the 190's to close to 230 was due to a seized electric cooling fan and it's blown fuse.

2. pushing coolant out overflow tube was found to be a crack in the block, which allowed the engine to pressurize the cooling system...

 

Hello again,

Got the the new expansion cap today. Did a flush and reverse flush. Took it for a drive and the temp got to 204F, once it got back in the driveway and the engine off the coolant came out the overflow again.

Could this be a clogged radiator?
Any inexpensive solutions to this or is there a a good aftermarket unit I can get that would be a plug and play without any modifications?

Thanks

 

get the tester fluid to see if you have exhaust gas in your coolant,if it turns yellow you'll know.btw just curious southern if you didn't run your ac [fans] what temp would your truck run at