Coolant loss in reservoir

MELINDA JACOBS MAYR

MEMBER
2005 HONDA CRV
4 CYL
4WD
AUTOMATIC
158,000 MILES

Two days in a row I have noticed my coolant reservoir doesn't show coolant in it. Doesn't overheat. Fill it up to max line, drive maybe one and half hours and later check reservoir and it's gone. Nothing on driveway or on engine under the hood. Where and what is going on with coolant?

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Hi Melinda,

If you don't find any on the ground then your engine is burning it. This is a pretty good sign that your head gasket has failed and needs replacement.

Here is a guide that will help test it. Also, I attached the process for replacing it if you want to do it yourself.

https://www.2carpros.com/articles/head-gasket-blown-test

In short what happens is the coolant needs to flow from the block to the head of the engine and back again. This is the cool the complete engine. In order to seal the coolant passages and oil passages from the combustion chamber, they use a head gasket. Over time, these fail and allow the oil and coolant to mix, the oil or coolant in to the combustion chamber, or all of the above.

When this happens the only repair is to replace the gasket. If you notice while driving or when you start the engine there is probably a large amount of white smoke coming out of the exhaust. This is the coolant being "burned" in the engine.

Please let me know if you need anything else. Thanks

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