AvRog

Did the search for expansion tank on the forum, can't find the answer. Is there a pickup tube in the expansion tank?

oldsarge

Don't know what year you are talking about, but yes, most of C3 have a pic up tube.

DonnieP73

There is on my 73 to pull back into the radiator and the other side of the cap has a
over flow tube on the outside but not on the inside so if the tank fills up it can escape.

Donnie

Mike Ward

No. None. Ever.

DonnieP73

If you are referring to a true expansion tank, then Mike is right.
If a coolant recovery tank, then yes.


Donnie

Mike Ward

OP has a '69. No coolant recovery tanks prior to '73.

DonnieP73

I didn't see what year he had, that is why I just said my 73.
You are correct about the coolant tanks, sometimes the names
of parts are incorrectly called something else.
Sorry about the mix-up.

Donnie

AvRog

Thanks again Mike, I ask the question because when the system cools, if there is not tube sourcing from the bottom of the expansion tank then the rad would be fed air rather than the fluid. Am I missing something?

Mike Ward

Yes, you promised to post a pic of your set up. Doesn't sound stock.

Easy Mike

The expansion tank should never be empty. If you empty it, you've already lost coolant.

AvRog

I don't care if its stock. I have an aluminum rad, no rad cap. A line to the expansion tank that has a 16 lb. cap that would, if required vent to atmosphere. My question is should the pick up in the tank that connects to the rad have a feed tube to the bottom of the expansion tank?

AvRog

Its not empty and I have been previously running with an incorrect rad. 2 cap set up. I got a dewitts aluminum no cap. Now that I am relying on the expansion tank to work, I want to ensure it will. I'm having trouble seeing proper operation without a pick up in the tank.

The car is a 1969 L68 (427 Tri). I believe it to be functionally correct.
Mike W. I'm working on the pic. Camera U/S due to kids, and I need to fire up my photo bucket account.

AvRog

Check this ?
http://s1049.photobucket.com/user/Av...?sort=3&page=1

MelWff

there should not be any feed tube to the bottom of the tank. The tank is higher than the radiator, as the fluid expands in the radiator it goes through the small hose into the tank thus the radiator is totally filled with fluid, no air pocket in top of radiator. There is a fill line on the tank about half way which is the level when cold. Looked at the pictures and am somewhat puzzled. Dont you have two small necks on the bottom of the tank? If so are they connected inline to one of the heater hoses? The small neck on top of the tank should have a hose going down for any overflow.

AvRog

Interesting, should my tank be connected to the heater hose?

Mike Ward

Ah. You're trying to force a round peg into a square hole. That's an expansion tank that you're attempting to use as a coolant recovery tank. Won't work.

That style of tank should have two connections on the bottom:


The connections are essentially spliced into the heater core hose.

AvRog

Cool, It looks like there are removable plugs on the bottom of the tank. I wonder if I can pop them off and make connections.
What if I Bubba a tube so the into the tank will pick up from the bottom?

What if I leave it as is?

Easy Mike

Order the assembly instruction manual (AIM); make the correct plumbing connections shown in the AIM; and your tank will function as it was intended.

You would not need to Bubba anything.

Mike Ward

I'm trying to figure out how you filled the cooling system.

MelWff

You dont seem to be clear on how the tank functions. The bottom pipes should be connected to the appropriate size heater hose and putting a tube in the tank will do nothing.