Yes , I tested it and it seems to be working . I just took it out again and it only got to 150 . I checked the upper hose and it was hard so I believe it is holding pressure . The radiator was hot but touchable as was the upper hose . I'm at a loss .

 

There is no such thing as having too large of a radiator. The thermostat regulates the flow of coolant through the engine. If the coolant is too cool, the thermostat will close down and wait for it to warm up.

Are there any holes in the thermostat? Is your heater core plumbed correctly? Anything that could allow for flow to bypass the valve in the thermostat?

 

Latest news ... Finally got it warmed up . I had to completely block off the radiator with cardboard . Once i removed the cardboard it took about 5 mins to drop the temp back down to 150 . It was about 85 here yesterday so outside temp wasn't a factor .

 

My statement still holds true. You have something that is bypassing the thermostat allowing coolant to flow through the system at all times rather than being regulated by the t-stat.

If you can, take some pictures of your engine including any lines to/from the engine that are thought to be coolant lines and post them here.

 

Ok . Here is a couple of pics . If there's different views you need let me know .

 

Replaced t-stat again . No change . It's about 80 here today and temp will not go above 150 still . Hot air comes out of the heater but upper hose is not hot . This sucks .

 

Is there a fan clutch? It could be stuck/dirty? Would that cause it? Google that one os may not apply. Centrifugal release between fan and pump?

 

When mine had a bad fan clutch it ran hot so I would think that wouldn't be a problem.

 

I can spin the fan by hand . I had a buddy hold it while I started the enginge so I think the clutch is ok .

 

I took it to a shop today and they claim that it had 10 codes in the computer . I had checked it earlier using the jumper method and there were no codes . They are claiming i need a new ECU or chip . I will get the codes and post them later .