[SCHOON]

I have an aluminum unvented overflow tank on my 69. It doesn't seem to be working the way it should. Do i need a special radiator cap when using this setup.

[dawg]

yes I found out you need the venting cap.
(cap with the handle on it)
i too have the same system and after using the venting cap the coolant gets sucked back into the radiator as the engine is cooling.

[SCHOON]

Can you get a vented cap in crome?

[SixtyAte]

Yes and polished aluminum also. Just use the search engine Google and type in chrome vented raditor cap follow the links. Most of you local Pep,Zone,Etc parts stores should have one.
Kev

[SCHOON]

Thanks, I will give it a try.

[JohnZ]

Originally Posted by SCHOON

I have an aluminum unvented overflow tank on my 69. It doesn't seem to be working the way it should. Do i need a special radiator cap when using this setup.

You need a radiator cap with a 2-way vacuum/pressure valve (common item) for a coolant recovery system to function, but more importantly, a coolant recovery tank must also be vented or it won't work.

[JimM]

here's a shot of mine. It tucks in so good you can't see much.
http://home.comcast.net/~Jimragtop/P0002588.jpg

you can't see it too good, but there is a valve on the bottom to drain it, a small vent hole in the top, and the inlet tube goes all the way to the bottom so the system can draw the coolant back out.

Don't know if Eric is still making them, but it's a fine peice.