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Discussion Starter #1
Ok, so I drained the radiator and engine block in order to replace the water pump. The water pump replacement went fine but now I've added the new coolant (Zerez G0-5) the temperature gauge reads 100+. It used to read around 87 on a hot day before. I tried burping the system using a funnel by setting the heat to high (I have the latter climate control system) and the heat system to vent. I also raised the front of the car. The thermostat is a couple of years old, it's a 79 degree one that I checked was working before I put it back in. The top radiator hose gets hot so I know the thermostat is opening. There's little heat coming out of the defrost vents. I'm flummoxed as to why this is happening, is there some trick I'm missing?
 

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Check for something you may have not tightened correctly such as a hose clamp or perhaps a hose may have been damaged during removal. Replaced the drain plug washer on block?

Other than that, have you hand pumped the upper radiator hose with radiator cap off, engine at 1200rpm? 2.5 gallons to fill...close to that?
 

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Discussion Starter #3
thanks, yep the engine drain plug washer is new, I've revved and pumped the upper radiator hose, all clamps and hoses are good, and it did take two to two and a half gallons. I'm pretty sure there's an air pocket in there I've just no idea how to get it out
 

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Replace the tstat to make sure it's good. Drill some small holes in the flange to help it heat up and open. It's tough to get that upper hose full and hot.
 

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Did you install the thermostat on the same position it was? I am not sure about the t-stat on the M110, but on the 617 it has an arrow that must be facing some specific direction so air can escape the system.
 

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Did you install the thermostat on the same position it was? I am not sure about the t-stat on the M110, but on the 617 it has an arrow that must be facing some specific direction so air can escape the system.
He is right. I had a problem with my 280 getting hot after I replaced the thermostat. You need to make sure that the arrow is facing the right way. Mine was 180 degrees out. I pointed the arrow the right way and am having no problems with cooling.
 

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Discussion Starter #7
thanks but i tested the thermostat before putting it back in and it was the correct orientation with the hole at the highest point, just as it was when it was working correctly. I've ordered a vacuum flush tool and will be trying that out this weekend.
 
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dave33333
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