Me, if there was no sign of circulation when it is hot, I'd suspect the t-stat. Do get a quality T-Stat, preferably from Jeep. There really IS crap for sale there, and it matters. My renix is "closed system", so I can't clearly see the flow change through the Rad cap when the t-stat opens, like you could on yours.

Also, DJB has posted photos of water pump impellers that where just a flat disk, no "business" left on it's business part's.

 

I would rather have springs in my lower radiator hose so I purchased some.

 

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That's fine that you choose to have springs (we won't worry about the metal composition). I am perfectly happy living in a "spring free" household.

 

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