You have a second cap in the top hose iirc.How do I verify coolant is circulating. Pop the cap and let the car get to temp and see if it starts moving
Take the cap off
If you have no restrictions the coolant will stay below the level of the cap while ideling. Once the thermostat opens you will see flow.
To reduce a potential mess get a piece of rad hose that's big enough to go around the cap opening and is a few inches long to extend the hight a bit.
Now if coolant starts flowing out of the cap hole on the hose you might have a very restrictive rad.
Some questions...
No particular order.
- How much coolant did you put into the engine?
- Did you test the new thermostat
- Is the thermostat installed correctly
- When ideling is the fan coming on
- Is the pump housing designed for the inlet to be on the lower passenger side. I'm assuming you have a cross flow rad.
- You could have a big trapped air pocket. It happened on a 318 I had. I filled the rad till coolant came out. Put the cap on and went for a test drive. The temp gauge rapidly got to the oh **** range. I headed home and shut it off. I could hear boiling on the engine. After it cooled off I was able to add about 3/4 gallon of coolant.
- Should always test before putting it on. Boiling water here in CO is more than hot enough for a 180 or even a 190 stat to open
- The bulb of the stat should be facing the block, can the stat open on the pump housing and the t stat cover? I recall an engine ( Ford?) that required a specific stat or it could not open. Take your previous stat and force it open with a wedge of some kind and set it in the housing opening, does it sit flat in the housing
- I think you answered that already is the airflow the correct direction
- If you have a cross flow rad and the inlet and outlet are on the same side the rad has to be internally baffled to force the coolant to snake through the rad. If the internal baffle is missing the flow will go from inlet to outlet without going through the core
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