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Car radiator and over heating

Hi,

I own a 2001 Hyundai Elantra. Recently it was pointed out to me that there is a leak in the top tank of the radiator. This appears to result in dried coolant deposits around the leak and the area surrounding the radiator cap.



The thing was that I noticed this pattern of mess at least 1 month ago but did not realised that it was anything to do with a radiator leak. In fact in that last month, I have driven the car for over 600 miles and have not seen the temp gauge go over the typical half way mark.



Is it possible for the radiator to be broken and yet not to result in any visible over heat (assuming the temp gauge/sensor is not broken).?



When opening the radiator cap (after over night cooling of car) I can still see a low level of coolant in it.

Yes, it is possible to have a small leak in the radiator and not have an overheating engine, but you can’t count on this to last forever.

Eventually the coolant level will become too low and the engine WILL overheat.

If you know the radiator is leaking I suggest you have it repaired or replaced before it gets worse and damages your engine. The radiator should be completely full, with coolant all the way up to the cap.

I agree with the other poster. Last summer the radiator on my 2000 Blazer started leaking at 95k miles. There was a small crack on the side tank near the top. The coolant only dropped an inch or two lower in the radiator so there was no overheating. However there was no guarantee that the crack wouldn’t increase in size, so the most prudent thing to do was to replace the radiator before it failed completely.

It’s not cheap, but it’s much less than replacing an engine and radiator.

Ed B.

I agree that it would be better to get it fixed. However, here are two tips in case you decide to tough it out:

  1. Keep the radiator full with proper coolant (not plain water). This means checking it regularly and having coolant available, even while travelling.

  2. If the engine does start to overheat, pull over and stop IMMEDIATELY.

Do you really want to deal with the hassle of #1 or the risk of #2?