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I just refilled the engine coolant reservoir about 4-6 months ago to max and the level is back down to the minimum level again. It doesn't seem normal to drop to the min level so quick does it? It's been staying there so just wondering if I should be concern to refill it to the max line again if it will go back down to the minimum level again as a normal process.
 

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That level will change between hot and cold, too. If the engine is hot it will be higher, cold it will be lower.
 

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That level will change between hot and cold, too. If the engine is hot it will be higher, cold it will be lower.
I always check it when it's cold, the level drops after a while.
 

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Did you check it when the engine was cold? If you filled it to max when the engine when cold, all those extra coolant is just going to spill over when the engine is hot, so you will be back to min in a short time.
 

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I think that filling the reservoir to the line labelled "Max" is safe. That still allows plenty of room for any foreseeable normal expansion of the liquid.

If you are filling it when cold and it drops in a few months then you probably have a small leak.
All the cars I ever had never needed any extra coolant under normal circumstances, except perhaps once every five years or so. Whenever I had a drop like that it turned out to be a leak. Sometimes a small leak in the beginning, which I would just keep like that for years. In most cases the leak eventually got bad enough that I would notice drops of coolant where I parked. In my case seems like the leaks would eventually become significant enough to spill on the ground on some colder winter morning (at least as cold as it gets in California). Perhaps that is when the rubber and seals shrink the most and the leak is more likely to become worse.
 

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Assuming the OP is saying exactly what he did, there is a fairly serious coolant leak. The #1 thing we don't want it to be is a cracked head. The next worse thing is a blown head gasket.
OP, check your oil and look for tan-colored scum on the dip stick. If none, you might have a harmless leak like a bad water pump or hose. Check the floor under the mat on the front passenger side - if coolant is there, it's the heater core. If you're lucky it will just be a loose clamp or a bad hose.
If you find the scum on the dipstick, you might be looking at an engine. At best the coolant hasn't harmed the bearings/cylinders and you just have head/gasket work.
 

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Having the coolant level drop from max to min on the reservoir (which is a very small amount of coolant) over a 4-6 month timeframe isn't really a cause for concern. Not sure if it's common on these cars, but I do know that on Toyotas, sometimes an old radiator cap that's not very tight can cause some coolant to evaporate slowly over time.
 

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Also not disclosed (this thread is 10 months old as I type this) is if the timing belt/water pump had been replaced (and/or the current miles on the van) I have had this issue when the system has not been properly "burped" after replacing the fluid. Once brought to the proper level, it does not go down.
 

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Good point about water pump replacement. I just had mine replaced and my mechanic filled the coolant to the top line in the reservoir. After a 500 mile drive, the level fell down to the low line since the system got all the air out, I topped it off and now it hasn't dropped from the top line.
 

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Good point about water pump replacement. I just had mine replaced and my mechanic filled the coolant to the top line in the reservoir. After a 500 mile drive, the level fell down to the low line since the system got all the air out, I topped it off and now it hasn't dropped from the top line.
In general, this is what I would expect for a car without problems. (y)

Whenever the cooling system is opened, air will get in, and it may take some time for the bubbles to work their way to the coolant overflow reservoir. And that's not a problem at all.

But once the bubbles have escaped and the true level shows in the coolant reservoir, it should stay that way for a long time unless something is wrong.

So losing 1" of level over a few months is not normal. It should be steady. I'd expect a leak vs. a head gasket issue as my first guess. A HG would be likely to be much faster.

(I know the original problem / situation is ancient history, so this is general advice here)
 
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