Radiator overflow tank: bad idea?

[JBNeal]

Has anyone tried to install a radiator overflow tank for their flathead? I've seen a small cube tank at JC Whitney and O'Reilly's and wondered if anyone had tried to keep the pavement clean with a similar contraption. I stopped for gas with the 1 ton during the summer and it watered the pavement purty good...an old timer nearby quipped "yep, I got that problem too"...didn't know if he was talkin'bout himself or his buggy.

Anyhow, yeah I know this cube tank is plastic and would hardly look original. I was thinking that I could fab up a bracket to put in front of the radiator area or above the radiator under the hood. Maybe feeding a hose from the bottom of the radiator overflow tube to above the coolant level line...my concern would be that once the overflow began that it would siphon out the radiator eventually.

My aim is to keep this truck as close to stock as possible, but with small improvements to keep it clean, such as the PVC system and possibly this overflow tank. I've seen several of the paper air filter conversions and I'm leaning towards trying this...back in July 2008, I got in a hurry & forgot to tighten the clamp on the oil bath, and the first right turn I made at speed I realized whut I had done...
 

  

 

Constructive input is much appreciated

Edited February 4, 2022 by JBNeal
revised picture

[MBF]

Good morning. I believe that the overflow tank is designed for a pressurized cooling system-which our flathead vehicles do not have. Since the system isn't sealed-it wouldn't be able to create a vacuum to draw the fluid in the overflow tank back into the cooling system if and when needed. The overflow tube's purpose is to get rid of excess coolant that would otherwise boil out the cap and cover the engine once it "hit the fan". If I'm wrong-someone here will surely correct me. Just my 2 cents. Mike

[4852dodge]

The overflow tank is supposed to catch the excess coolant as it expands and return it to the radiator as the system cools keeping the radiator full. As long as the radiator cap has a seal to the radiator the recovery tank should work. The system in our trucks were designed to have an air gap at the top of the radiator, if the tank is too full it will send the excess out the overflow tube, unlike the modern motors that are designed for a catch tank and a full radiator.

[Young Ed]

The 66 wagon my Dad bought late last year has a metal round recovery tank. I think the previous owner said it was summit. Looks like it would fit in a little better. Certainly would if you could get it plain and paint it black. You can just see the top of it in this picture.

[chopt50wgn]

what you can do is ....take an old plastic coke bottle, hang it in the motor compartment........fill the rad and drive it, when the coolant goes into the bottle, empty it into another jug. Keep doing this until no more coolant goes into the coke bottle. Then you know that all the expansion is taking place within the radiator and pissing it out.

[lugnut123]

On my B3C it has a pabst blue ribbon beer can stuck up on the radiator overflow.

[pflaming]

Hey Lugnut: Do drink the liquid in the beer can cold or straight up!

[lugnut123]

Heh heh just hope I don't get a DUI for open container law.

[1949P17BC]

Budweiser Can worked for me.

[cwcars88]

I have a stock Model "A" that I just let it blow intell it finds Its owen level and it stops blowing. That said I have fellow "A" club members that have catch can's that do work on the non pressureized sytem. What they did was mount a container on the support rods that go from the firewall to the radiator, which is a little higher then the radiator. It is a vented container, the water just drains back to the radiator.

Wayne

[JBNeal]

Catch can, that's the ticket...I knew there was a term for whut I was thinkin'. Yep, pressurized systems use the overflow when pressure builds & whutnot. Putting the reservoir above the main reservoir would prevent siphoning and allow excess coolant to exit the radiator without makin' a mess like an excited dalmation.

[John-T-53]

Danchuk Mfg in Santa Ana, CA makes a tank for $45. These tanks are made for 55-57 Chevys but their vertical design would fit many applications. They're stainless with a billet aluminum cap. The hoses connect at the bottom of the tank for a clean install. There's also an overflow line out the tank should things get too hot.

[Flatie46]

I've seen some in the speedway catalog.

[Dan Babb]

You could use a Jack Daniels bottle (or whatever your favorite beverage it) to use as a catch-can. Once you use the 2-liter bottle trick, it would most likely not get much use, but I agree it would be nice to have if you're out on a really hot day and driving the engine longer than usually or stuck in stop & go traffic.

Then if you notice the bottle has some fluid in it, you can judge when it's time to put some extra coolant in the radiator.

[JBNeal]

I'm leaning towards fabricating a 'tank' out of a piece of 3" pipe (possibly PVC) capped on both ends, with one end tapped with two fittings. One fitting would be a barbed NPT nipple for a rubber hose coming off of the overflow tube. The other fitting would be a vent of some sort...it's a work in progress

[Dan Babb]

You could go with something like this from Summit:

http://www.summitracing.com/parts/SUM-G1473/

It's under $20 and would look better than pvc pipe.

Or spend more money for the flashy aluminum piece (close to $100).

http://www.summitracing.com/parts/MOR-85505/

[cwcars88]

I have to same overflow tank on my 57 chev that John-t-53 shows in the picture, but I don't see how it will work on a non pressure system.