Radiator, no overflow tube

I

izze

Member
I've been working on my vehicle over the last few months. Fixing things here and there. The engine runs a little better after each repair. And with each repair, I drive the car a little more. And with each drive, the engine will overheat sooner then the last drive.

I tore apart the cooling system. And I found that the gooseneck is in pretty bad shape. After draining the system, I found a lot of junk sitting atop the tubes in the radiator. (2 tube core) I replaced the gooseneck. I back flushed the engine. Back flushed the radiator. I let the radiator sit in vinegar for a few days, and continued to backflush it once a day. Now the tubes look really clean. And when I get the system put back together, I'll run it with vinegar for a week or so. Continuing to flush as I go.

I'll check timing. Re calibration the carb mixture. Verify the correct coolant level, etc.

So, the radiator makes a hellova mess every time it overheats. Boiling over at the cap, and draining all over the front end. I thought I would take a look at the overflow tube when I took the engine apart only to find that there is no overflow tube. I have 3' of 1/4" brass tubing. And I feel like it would be really easy to drill a hole into the radiator top reservoir, and weld in the tubing to make my own overflow.

Any advice on adding in this tube?

And is it common to find no overflow on these older radiators?
 
The radiator might be a bad reproduction or a previous owner(s) might have adapted a radiator from another car. Someone here might be able to identify it if you post a picture.

You probably should replace the gasket in the radiator cap and run distilled water with rust inhibitor until you fix the radiator.

What model and year is your car?

David Serrano
 
I use a thick O ring for the radiator cap gasket. That stopped it leaking at the cap. But even a fix for the cap will not keep it from overflowing if you do not have the overflow tube. You can use plain soft solder to install the overflow tube. I think it works best if towards the back of the radiator but double check as my memory may not be accurate.
 
With the overflow tube missing you might be pumping water out of the radiator as you drive causing the engine to overheat.
 
I don't believe a two tube core radiator was ever put in a Model A. All radiators were either 5 row (28-29) or 3 (30-31)row cores. The cooling capacity of your radiator probably isn't enough to cool a Model A engine. I would recommend replacing it with an original 5 row core radiator.
 
Exactly nkaminar. The backside of the radiator has an overhang where I was considering adding the tube. Running it down the drivers side. I'll also replace the gasket on the cap.
 
Last edited:
I would add the overflow tube but go with copper instead of brass and soldering instead of welding. I also put a 2" roofing nail in the overflow tube of mine to help eliminate it splashing out while running at 45 m.p.h.
 
You must log in or register to reply here.
Back
Top