Does the coolant overflow need to be a closed system
 

Or can it just flow and suck from a bottle? My current tank by the battery broke and it was old and just the hose stuck into the tank and the lid was loose or non-existent. I am probably going to order the washer tank to replace it but I am wanting to know if I can mount a bottle somewhere as a get me by.

Re: Does the coolant overflow need to be a closed system
 

The coolant recovery system is a simple bottle for expansion collection when hot. As the engine cools coolant is sucked back into the radiator. A temporary plastic bottle can be used until you replace the OEM bottle. The hose from the radiator needs to extend close to the bottom of the collection bottle.

Re: Does the coolant overflow need to be a closed system
 

I just re-purposed my washer fluid container as my wipers aren't working right now anyway. I re-mounted it on the passenger side fender and it already has a cap with a nipple and suction tube in it. I have seen older trucks with a Jack Daniels bottle and cork.

Re: Does the coolant overflow need to be a closed system
 

The lid or cork is not sealed. It is vented.

Re: Does the coolant overflow need to be a closed system
 

Coolant recovery tank should be open to atmosphere. Not present on stock 67-72 trucks, but feel free to add one. I will have one in my truck.

Re: Does the coolant overflow need to be a closed system
 

On my truck I bought a tank from amazon, mounted it on the firewall, it's not original, but it works fine, easy to see and out of the way.

Re: Does the coolant overflow need to be a closed system
 

You probably already know that you'll need a radiator cap for a closed system. A conventional cap won't suck the coolant from the overflow tank as it cools.

Re: Does the coolant overflow need to be a closed system
 

I bought a tank from a member here it works great.
pictures here https://67-72chevytrucks.com/vboard/...d.php?t=855434

Re: Does the coolant overflow need to be a closed system
 

Nice engine bay

Re: Does the coolant overflow need to be a closed system
 

I have the AC in mine so I am limited where I can mount a tank. I posted earlier that I just robbed the wiper tank off the driver's side and put it on the fender by the battery.

Re: Does the coolant overflow need to be a closed system
 

Thanks for the tip Stocker! I didn't know of the closed system cap.

How do I specify one that will work with a 69 radiator? I.E what year(s) etc.?

Re: Does the coolant overflow need to be a closed system
 

Yes, was aware of that, but a good point to let everyone know. I would have put it by the battery, but have some extra wiring there from the vintage air.

Re: Does the coolant overflow need to be a closed system
 

Not sure what year(s) closed systems became standard. Caps for a closed system have two rubber seals -- others have just one.

I just went to my local NAPA store & told them what I wanted.

Re: Does the coolant overflow need to be a closed system
 

After searching this forum a couple years ago, here's what I used:
OER coolant recovery tank #551448
Dorman vented cap #82590
3/8 ID x 9/16 OD silicon tubing from Amazon

Was even able to use an existing hole on the inner fender.

Works great. No more overflow to the pavement on hot days!

Re: Does the coolant overflow need to be a closed system
 

I really like this with how clean it appears! Too bad I didn't see it before I did my version!

Re: Does the coolant overflow need to be a closed system
 

Hi Everyone,

I've been trying to post a rather long reply for several hours and have been kicked off several times or received the notice that the server is too busy and then be kicked off when I try later!

I've saved the text but I have to hunt up the photos each time so I hope to get back as soon a possible!

Re: Does the coolant overflow need to be a closed system
 

Hi Everyone,

I've finally given up! Too much of my day has been wasted and I need to get to work. I can try again late tonight when things aren't so busy.

I have a 1986 4WD K20 chassis for another project. Does anyone know if the steering box and pump will fit this wrecker?

It's still hooked together so I can swap the assembly if the pitman from the wrecker will fit the other box.

I'll post this question in another thread to see if it gets more views.

Re: Does the coolant overflow need to be a closed system
 

Those that have done this, what's the approximate volume required for this kind of setup?
Presumably less than 750ml, since a JD bottle works ;-)

Re: Does the coolant overflow need to be a closed system
 

Dorman makes several styles of coolant recovery bottles to fit almost any vehicle. I’ve installed several on my 60’s and early 70’a vehicles that were originally open systems and allowed overflow to go on the ground. Another advantage is the radiator stays filled right up to the neck compared to the open systems where the top inch or so of the radiator is not filled, exposing that area to oxidation and corrosion.

To answer your question, approximately a quart of coolant is what I see in the bottle.

Re: Does the coolant overflow need to be a closed system
 

That's what I was wondering. IF I fill the radiator, I'll need enough capacity to displace n quarts of coolant, or it'll just end up on the ground again

Re: Does the coolant overflow need to be a closed system
 

A windshield washer tank with coolant overflow lid on it is 1/2 gallon. I believe the dorman universal ones are about 1/2 gallon. The tank serves 2 purposes, to replenish coolant lost through weeping leaks, and to catch and refill from expansion and contraction. When I put my dorman tank in above the electric regulator, I had about 70% green coolant to water mix and I noticed the tank was the same level hot or cold, so I was getting no noticeable expansion. And the cooling system was new and I didn't drop any of the level due to coolant loss over a year or two. Now I believe the water pump is probably giving up a little or I may have a small leak at a hose connection, because I need to re-fill the tank up to about 1/2 way full every few months. And with a 50/50 mix that my mechanic last put in, it does expand and contract by about 3/4 inch of fluid level between hot and cold.

Re: Does the coolant overflow need to be a closed system
 

When I got this thing, I just filled the radiator and it would use the ground under the heater core for expansion ;-)

Re: Does the coolant overflow need to be a closed system
 

I don't know the capacity of the OER #551448 tank I mentioned above, but I doubt it's more than 2 qts. Even after a drive on a 90 degree day, I've never seen it more than 1/3-1/2 full.

Re: Does the coolant overflow need to be a closed system
 

I was fixated on a smallish one for the front of the rad support, but it's 600ml, so probably a bit small. Most tanks aren't spec'd with volume, so trying for a similar shape with more capacity.
The two fender-curved options look good too:
OER 551448
OER 493072

Re: Does the coolant overflow need to be a closed system
 

I am kind of looking for a way to mount a large JD bottle on the inside fender and a stopper and hose for it.

Re: Does the coolant overflow need to be a closed system
 

Here’s how I have the Dorman 54002 mounted in my 71 Jimmy. The hose runs from the radiator overflow, under the fan shroud and up to the coolant reservoir. Don’t know why the pic is rotated 90*.

Re: Does the coolant overflow need to be a closed system
 

Here is some links for fabrication Ideas.

Bracket link: https://cnafabrication.com/products/jd-coolant-catch

Video:

Re: Does the coolant overflow need to be a closed system
 

Not a C10 but my 80 Camaro has a stock plastic over flow tank. One hose from the nipple on the radiator cap neck to the plastic tank on the fender. The over flow tank is vented. Pic.