How to temporarily fix a leaking car radiator
Radiator leaks caused by a puncture, loose component, or speed bump impact cause coolant to spray or drain rapidly, leaving the vehicle at risk of overheating. Liquid stop-leak additives can temporarily seal minor holes, but they are only a short-term patch before the radiator must be repaired or replaced.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Getting the vehicle towed to a mechanic
- 2Checking fluid types and colors to identify the leak source
- 3Avoid using leak-stop additives to prevent clogging or gumming up system lines.
- 4slapping the hose back on to drive short distances
- 5using multiple clamps
- 6applying silicone RTV or J-B Weld plastic bond to the radiator neck
- 7bypass the internal transmission cooler to an external one if the radiator still holds pressure
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“I went over a speed bump in my 2005 Ford Fusion, something snagged and now it’s leaking smelly yellow fluid, fast.”source ↗
“Radiator hose detached back in march cus the clamp broke so I got a new clamp and everything was fine up until tonight it came off again and coolant went everywhere but the clamp seems.. fine?”source ↗
“I slapped it back on and drove home cus I was less than a mile away but when I got home it was off again”source ↗
“New radiator time”source ↗
“There is no easy fix for this. Its time to replace the radiator.”source ↗
“I recently discovered that my truck has a tiny hole in the antifreeze compartment and started shooting out fluid. Any recommendations? I’ve been told that there is some additive to stop that leak temporarily…”source ↗
Where this came up
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