Best way to fill a cooling system for the first time - 351w

[silver_pilate]

The last time I filled a cooling system on a new motor was over 20 years ago, and I made a huge mess. I wanted to see what everyone's step-by-step process was for filling a new cooling system. I have a 351w based motor with the FFR aluminum radiator (has an upper and lower drain valve in it), and I have a fill point on the upper radiator hose as the highest point in the system with a 16lb pressure cap. I'm not running a heater.

Thanks!

--Nathan

[Papa]

I used one of these:

Lisle 24680 Spill-Free Funnel https://www.amazon.com/dp/B00A6AS6LY..._qXLcDbD4BHSSH

Here's a video of the process:

https://youtu.be/BQk9HpuIrmA

[skidd]

After struggling to correctly "burp" my cooling system the 1st time after filling it from the radiator cap.. which is the highest point in the system... I said heck-with-it..
Now, when I fill my system with coolant.. after being empty of course..
I pull the radiator cap off. and I pull the 1/2 NPT plug behind the thermostat and beside the distributor... NOT the one in the thermostat housing, if you even have one there.
Then use a long skinny funnel and slowly add until it it tops up. I can easily get over 2 gals into the system this way with no air bubbles.
Put the plug back in, and add the last bit of fluid through the radiator cap.
Add the the "cold" line on the overflow tank.
Fire it up, and get it up to operating temps.. go for a drive around the block..
Check the level in the over flow.. it "should" have gone up, but might not have gone up much if there was still some air.
Let the whole system cool down, and make sure the overflow never goes dry.
When it's cool again, check the tank level, make sure it's at the "cold" line...
Do that heat/cool cycle one last time if you are so inclined...
Last time I did this.. just last weekend actually... it went smooth as butter, no mess.. no burping.. no fus.

[karlos]

Not cheap but works beautifully, especially for a first fill. Completely eliminates air pockets and the need to check/purge/fill. The reviews at the bottom of the web page pretty much say it all.


https://www.amazon.com/UView-550000-...gateway&sr=8-2

[CraigS]

Skid has it. The key is that plug in the manifold. I pull that and fill at the T-filler. It runs in very nicely as the air comes out the plug (on mine it is a heater hose nipple). As soon as coolant comes out there, put the plug in. Top up at the T-filler the last several ounces. Now put the pressure cap on (and I can't emphasize this strongly enough) and don't remove it again. Fill your overflow tank maybe 1/4 way. Fire it up and be sure to get it to temp and be sure the t-stat opens. You can verify that by the top rad hose being hot. I like to run the engine five minutes or so at 1500-2000 figuring the faster flow will help move any bubbles better. Shut it off and let it cool completely. 3-4 hours and be sure the overflow doesn't empty itself. Any further coolant goes into the overflow tank as some is sucked into the engine. I usually do 3 hot cold cycles and I will admit I drive the car on the last 2 cause it's too boring sitting running it in the garage. But I am never more than a mile away so I can head back if needed.

[Bob Cowan]

Drill a small hole in the base plate of the thermostat, 1/8-3/16". Install the thermostat with that hole at 12 o'clock. Then just fill it with a bucket. It will be pretty much self burping.