Replaced my thermostat and drain the radiator. Trying to pull a vacuum on the system but it runs forever and nothing happens. About to burn my air compressor up. Do I have still too much coolant in it? How do you get it all out. I feel something going on at the bottle and hoses.

 

Initially, I made silly mistake of NOT accounting for drain hole in coolant expansion tank filler neck. I needed correct adaptor to cover up this hole and then pulled good vacuum.

 

my filler tank has two smaller hoses at the top. Looks like the overflow one could be on the left. I did discover that the thermostat seal was the wrong one and leaking badly when I put water in the reservoir. I have to order one at the dealer, coming tomorrow. Thanks

 

why would you drain the radiator to replace a thermostat?? Its right up front... easy to swap out in under a minute. Then simply run the engine at idle with the heat on full blast for a few...

 

Looks like someone put a leak sealer in it. That’s why I drain the radiator.

 

Got the right thermostat ring from the dealership and it is thicker than the aftermarket one. No leaks now and vacuum tool worked but could only pull up to 15. It held so I opened the suction and filled it up with coolant and distilled water. Haven’t tried it on the long run yet to see if it solved my problem.

 

The overflow hole in the coolant tank is rectangular and molded into the plastic in the neck where the cap is. I cut a piece of hard rubber into a wedge to place in the hole, there is also an adapter available with an extra long plug that goes down into the coolant tank a couple of inches to plug the vent for pulling vacuum, Cutting a rubber wedge was easier and much cheaper. Drawing a vacuum to refill coolant is such an efficient way to do it though.

 

I really don’t have a neck where my cap goes. My overflow tank has two small hoses, one on the left and the front facing the engine.

 

That's too bad. Start looking for a new radiator when you find your truck starts overheating.