Technical Radiator overflow tank

I need to put an overflow tank on my 34 Dodge and I have read some of the posts here and can't quite figure out what is correct. Most of the tanks I see for sale have two tubes, the guy from Speedway told me one is for overflow. It looks like they feed from the bottom with a cap on top. Just looking for some input on what works best.
thanks, Carpenter Joe

 

The one that ends close to the cap is for venting if the overflow tank gets over full.

 

http://www.speedwaymotors.com/Speed...-Overflow-Expansion-Tank-3-x-10-In-,2953.html
Here is a link to the kind of tank I am looking at. Both tubes are on the bottom.

 

Looks like this on the inside...

 

Now I understand thanks Moose!

 

One line is for inlet, the other is to expel over-flow. If you looked inside, you'd see how it works. It's actually a fairly simple process. Fluid enters the inlet tube (which goes near the top) and rises accordingly. When the tank is full, the over flow expels from the other tube, which also goes near the top.

 

that style tank is properly used as a recovery tank - when running proper radiator and cap the fluid will expand out to the tank and when system cools fluid will be drawn back into radiator. some just have a tank/can/bottle, etc to catch fluid that is pushed out to hopefully prevent it from just going onto the surface below.

 

the short tube on that one goes to the radiator, the long tube drains (to the ground) when it gets too full.

Do you really need one? an alternative is to not fill the radiator completely full, leave an inch or two of air in the top radiator tank, and don't worry about it.

 

I use a $10 Dorman tank, 1 hose from the radiator, and it works well.

 

I use a 16 oz. Pabst Blue Ribbon can on my built 318 in my 33 Dodge coupe and have never had a problem. And I had the benefit of being able to drink the original contents.

 

Everyone knows Schlitz is where it's at

 

I still use an old gas can or reasonable collecting device and a dip tube, IE let my hose lay in the bottom of the receptacle. A catch can is just not that technical.

 

when someone said something about the PBR can I just knew Squirrel would chime in!

 

My preferred overflow bottle is a GM Optikleen bottle and mount. Mount it on the inner fender or core support, put a little antifreeze in the bottom and plug a hose into it. Works great. and you can take the bottle out and clean it if it get nasty real easy. I have found several over the years in junk yards .

 

I made my own out of exhaust tube(body) and brake line(tubes) and powder coated it when I was done. I have the inlet tube coming out of the top, over flow out of the side at the top and a drain petcock on the bottom.

 

Do you really need one? an alternative is to not fill the radiator completely full, leave an inch or two of air in the top radiator tank, and don't worry about it.

Absolutely correcto mongo!

 

made one from pvc tube with 2 end caps...
should have gone through the bottom as the heat beat the daylights out of the threaded holes on top...

 

I put one on because it seemed like any time I parked in some bodies nice driveway it would decide it was going to puke a bit. With the tank installed I only have to worry about the oil spots I am leaving.

 

An aluminum water bottle works for me.

 

Best reason outside of needing one to run at the drags I can think of. That and if it leaves a puddle with antifreeze in it some animal may decide to drink it.

 

Generally they won't leave a puddle after they find their level. But if it keeps puking, after it's down enough to allow for expansion...well, I guess you need one. Or fix the problem that's causing it to puke

 

Anyone had any bad luck running a glass bottle/Can and having it crack and break on them?

Sent from my SM-J727T1 using The H.A.M.B. mobile app

 

Depends on where you race I suppose.

 

Most folks don't race, I was talking to them.

 

I was just answering blue moon's question.

I am trying to remember the first car I owned with an overflow, I am guessing that it was a '70s Olds. I think the first late model car I owned was a '68 Mustang and I don't think it had an overflow as I recall. Most of the old hoopties that Jim and me started out with didn't have them, they are more of a modern deal, I don't recall any of my old cars puking unless they were overheated and those were usually hot enough to up puke past the radiator cap. A good stiff cap keeps a lot of that overflow tube stuff in the radiator. Also raises your boiling point.

 

Just a thought here, if you fill the radiator with oil and grease remover it would self clean the oil spots in the driveway.

 

Question on the overflow tube

Is there a recommended heighth to mount the tank in relation to the radiator ?

 

It doesn't really matter.

 

i use a WWII ALUM CANTEEN

 

I use a spun aluminum bottle I found in the lab garbage. it still has the sds stickers on it.