582 cyl head venting tube? closed? doubt it...

[wildirishtime]

On my recently acquired Kitfox 3, I decided to replace
the coolant with DexCool (who knows what it had!)

I pulled the cyl head vent tube and found that the
metal nipple where the 1/4" tube plugs on the RADIATOR
side of that vent tube is CLOSED.... it was NOT drilled into
the inside of the metal neck just below the fill cap?

Shouldn't that nipple be open to the inside of fill cap neck?
It's not an obstruction - it simply was never drilled.

I hope my question makes sense, please let me know your
thoughts before I drill it thru.
~Wild

[Mnflyer]

Are you talking about the overflow tube to goes to thew recovery bottle? If so yes it needs to be open, why in the world would you put Dexcool in your system?

[wildirishtime]

No the cylinder head vent tube. See attachment - tube on bottom right is not drilled thru into the vertical neck.

Why not Dexcool? 582 guys have been doing it long before I got into 582's since it's silica free.

[Mnflyer]

The cylinder head vent has to be open to vent and if it doesn't vent the engine will not cool. Just curious about the Dex cool I'm not a fan (It has caused serious problems in GM autos) I used the regular old green antifreeze and distilled water and it was fine for my engine. It's been 4 years since I converted my plane from the 582 to the HKS and I can't remember just how the vent tube from the cyl head went but I know if it doesn't vent the coolant will not circulate properly.
http://www.sancarlosradiator.com/dex-cool.htm