Fixing a Broken Radiator Overflow Tube: A DIY Guide

DIY Guide: Fixing a Broken Radiator Overflow Tube

A broken radiator overflow tube can cause the cooling system to lose coolant, resulting in overheating and possible engine damage. The tube connects the radiator to the overflow/reservoir tank, allowing excess coolant to flow when the engine heats up and then back into the radiator as the coolant cools and contracts. A break in this small yet critical part can disrupt this flow, leading to coolant loss and system inefficiency. Fortunately, fixing it is a manageable DIY task with the right replacement part, tools and knowledge. Here’s a comprehensive guide to help you repair this issue.

Why the radiator overflow tube breaks

Purchase a repair kit to fix your radiator

Plastic radiator tanks can become brittle and crack over time. One especially weak area is the nipple for the overflow tube that leads to the coolant recovery bottle or coolant reservoir.

The tube usually breaks off right here

In the past, if the nipple cracked or broke off, you’d have to replace the entire radiator. Not anymore. Just purchase an AirSept Permatube™ kit #65605 to repair the broken radiator overflow tube.

The kit includes a drill bit, stop, and two replacement overflow tubes. Simply drill out the old tube, then insert a curved insert through the hole in the radiator neck. Screw on the replacement nipple and O-ring and tighten. Re-attach the overflow tube, and you’re done. Find a full description on the DormanProducts.com site. Buy the kit on Amazon for about $21. That’s a lot cheaper than buying a new radiator.

©, 2019 Rick Muscoplat