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Coolant Refill

f10088

New member
Joined
Dec 21, 2019
Location
Chicago
TDI
Golf
I had to replace the radiator on a 2015 Golf following an incident with a curb. When refilling the system I could only get about 4.5 liters into the system and the specs are that it should take 6.5 liters. Is it possible the system retained 2 liters even though the rads drained completely?
 

ticaf

Veteran Member
Joined
Nov 15, 2018
Location
baltimore, MD
TDI
2015 Golf SW S Manual TDI
Oh yes, you won't completly drain the coolant by just draining the radiator.
You should vacuum fill, use VCDS or unplug the switchable coolant pump to get the coolant to circulate.
Some here, just refill and kept refilling while air gets out over a few days.
 

f10088

New member
Joined
Dec 21, 2019
Location
Chicago
TDI
Golf
Thanks for the response. I don't have a vacuum kit and want to ensure that the system is filled to the correct level.It comes up to temp fine and holds at 200 degrees so I might be overthinking this?
 

JM Popaleetus

Veteran Member
Joined
Mar 15, 2010
Location
Connecticut
TDI
Signature.
I would personally do another drain and fill, and call it a day.

But, as long as temps/level are fine in the interim, you should be good.
 

f10088

New member
Joined
Dec 21, 2019
Location
Chicago
TDI
Golf
Is the switchable pump the one under the engine? I have it up to temp but the hoses on the drivers side :larger diameter ones) don't seem to have any heat in them. Thanks
 

ticaf

Veteran Member
Joined
Nov 15, 2018
Location
baltimore, MD
TDI
2015 Golf SW S Manual TDI
Is the switchable pump the one under the engine? I have it up to temp but the hoses on the drivers side :larger diameter ones) don't seem to have any heat in them. Thanks
No, on the side, timing belt driven. If you have already driven the car to temperature, you probably should be fine. Just watch the coolant level. You'll get a MIL if coolant goes too low.
 

adjat84th

Veteran Member
Joined
Dec 13, 2008
Location
Virginia Beach, VA
TDI
'01 Jetta TDI/'15 Golf TDI
Oh yes, you won't completly drain the coolant by just draining the radiator.
You should vacuum fill, use VCDS or unplug the switchable coolant pump to get the coolant to circulate.
Some here, just refill and kept refilling while air gets out over a few days.
You know, I've had the coolant drained a couple of times on my car and never thought to do it this way! It makes total sense that the coolant never dropped in the reservoir until up to temp since the shroud doesn't move until all the way warmed up. If I recall, it took several top ups to finally get all the air out.
 
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