# No pressure in upper radiator hose



## trimfixer (Sep 29, 2009)

My 65 GTO overheated for the first time yesterday. The engine was rebuilt recently, and everything is new including the waterpump and thermostet. After it cooled down, I refilled it up and started it again. It climbed over 200 and the top hose had no pressure in it. It continued to climb to the point of pushing water out. I removed the thermostat and tested it in hot water and it did start to open at about 192. Looked to be fully open at about 210 or 215. It is a 180 stat. I have a new one ready to go in, but am looking for other suggestions to fix this. Thanks.
Steve


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## Eric Animal (Oct 28, 2007)

No offense, but was the stat installed upside down? I would try to run the car with no stat and see if you get good flow....a good trouble shoot, and only cost a gasket. Eric


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## trimfixer (Sep 29, 2009)

*No offense taken*

Thanks Eric. I appreciate the help. I did make sure that the thermostat was installed correctly when I removed it. This car was fine for the first month or so after the restoration and just yesterday it did this for the first time. I will try your idea.
Thanks again.
Steve


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## Eric Animal (Oct 28, 2007)

anytime...post the results....could just be a bad stat


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## pontiac (Mar 6, 2011)

180 should open sooner than your temps indicate. Get another thermostat. also do final fill radiator when engine is running after initial done just enough to cover the tubes. downflow radiators are never completely filled to the cap, just so the tubes are covered.


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## trimfixer (Sep 29, 2009)

Thanks, I will be installing new 180 stat today. Didn't know about the fill level. I should know if it fixes problem this afternoon.


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## GTO JUDGE (May 14, 2005)

What kind of shape is the radiator cap in? If it's got some age on it may be worth your while for a few $$ to replace it.


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## trimfixer (Sep 29, 2009)

Thank you GTO Judge. I did have an older cap on it. I have already replaced it with one that I had here. It appears to be in good shape. If thermostat doesn't work, new cap will be next. PS the Silver Judge is beautiful!


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