Should I be adding coolant to overflow tank directly?

[menotti]

Searched around and couldn't find a definitive answer. Say my overflow tank when cold is quite low, like at the minimum or below minimum but the expansion tank is topped off.

Should I be adding coolant to the overflow so it goes to about midway when cold?

Before I owned the Vanagon I rented one and the person renting it to me advised to fill the overflow tank if it looked too low while cold. But haven't seen that advice elsewhere.

Thoughts? Thanks!

[Zeitgeist 13]

Yes. But you'll want to monitor the frequency in which you're having to fill it. Since the it's a mostly closed system the coolant level shouldn't be varying much if everything is in working order.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[0to60in6min]

make sure that the main tank is full to the brim...

[Ahwahnee]

If you are referring to the tank behind the license plate then yes, it should be kept about half full. As I recall there is a MIN and MAX mark on there (faintly).

If it repeatedly needs topping up then you will want to know where is it going.

Possibilities include:

You have a head gasket issue that is sending coolant into the engine and out the exhaust

You have a leak

You have air in the system that is gradually self-bleeding

It is puking coolant when you are not looking

[menotti]

Thanks folks, yes was referring to the overflow tank behind the license plate.

Expansion/pressurized tank is full when the engine is cold.

After getting the van back from service, mechanic told me he topped off all fluids but the overflow is basically at the min line.

[Eric_Taylor]

Yep if everything is functioning correctly the coolant system should draw necessary extra coolant from the overflow tank, therefore you fill it there.

If it's not drawing it over, the first place to check is the cap, which seem to fail with a decent frequency. If the cap works properly, then the pressure of the system should create suction which will draw over fluid from the overflow.

[E1]

Coolant does expand a little when getting hot, too. If I fill to the Max line when cold, it gets to be too high above the Max mark when hot.

At least in my system, which is absolutely bled of air, filling it to the dead-center between Min and Mad is ideal, when hot it's barely under or right at the Max mark.
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‘84 Westy, 2.1L with Digijet, 5.43 R+P, GT Gears
"Adding power makes you faster on the straights.
Subtracting weight makes you faster everywhere."
— Colin Chapman

[Nickel_Nackel]

[WestyWanter]

Search function!

But a sweet smell coming from the exhaust, seeing physical leaks coming from the motor, milky looking oil, sometimes exhaust.

Use the search function to find out how you can diagnose a HG leak.

Expect around 2,000$+ to have a shop do it

[dhaavers]

Get, or ask your shop to use: https://www.amazon.com/Block-Tester-BT-500-Combust...stion+leak

<fingers crossed>

- Dave
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86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS>

[WestyWanter]

[Wildthings]

All the Vanagons I have owned seem to like to have the level in the refill tank at the minimum level when cold. Seems if I fill it higher it just gets blown out. I will fill it above the minimum when I have just bled the cooling system and know it will still take a bit more, otherwise I consider the minimum to be just fine.