I was out doing a check over on my fluids, besides oil, since I've put a new clutch in and I noticed that my overflow bottle was pretty much bone dry, at least far enough down that the tube was not moist when I pulled it up.

I was just wondering if this was an issue, is it normal to lose a bit over time, I'd say 2-3 months since I did the clutch job? I haven't checked my rad or upper cap yet as they are still warm, was cleaning the oil pressure sensor connector, since I'll occasionally get pressure readings at random times, and warmed it up to see. Anyways, I filled it back up and was just worried if this was a problem or some sort of early warning of a problem, coolant seals or something? I'm hoping I'm not nearing a rebuild, she's only got about 70k original miles and I really don't beat on her, except for the rare idiot on the interstate thinking their fart can just gave them 1,000,000hp.

 

Did the coolant light ever come on? Probably not a big deal... You could have a tiny hairline crack on the bottle cap/bottle, or the hose is aging and ever so slowly losing a bit. Coolant will evaporate slowly itself though. Fill it to low, then drive around a bit. Is it higher than low after? If so, let it cool and come back a few hours later. Is it back to low?

 

No the coolant light/buzzer never came on. I guess it could be a hairline crack, but the car is only driven 5 days a week to college and back and is always parked in the exact same spot, I would think there would be a small spot on the concrete right?

Which hose are you referring to? During that clutch job I did replace the upper rad hose with a CorkSport silicon one. Also, I didn't think coolant itself evaporated just the water. I did refill the overflow bottle though when I noticed, though I'm not sure as to how high as I also have the CS rad panel on and can't really see the bottle. But, based on what you said, wouldn't it get sucked back in after the car cooled down? I can't quite think of what that would prove right now though.

Oh, now that I think of it, the rad cap was cool, but the thermostat cap was hot so I did try opening it up to see what was up and I think some got sucked in somewhere cuz it started overflowing and got warm and I decided to stop until it cooled. Which I could probably go check now.

Edit: Just checked and rad is full and it doesn't seem like the overflow level has dropped any. I guess I'll have to check tomorrow after I get back from class.

 

Not necessarily.
I once had a rad with a very small leak that only manifested after the car was shut off and the rad built up pressure. It sprayed a very fine mist onto the hot core which caused it to evaporate...no traces after a few minutes.

That scary story nonwithstanding, I wouldn't worry too much, just keep an eye on level and see what happens.

 

I would think that the overflow bottle couldn't get pressurized like that, at least that's what I'm guessing the second tube coming out of the top of that cap is for and that it would just pour it out. At least that's my understanding/reasoning behind why I thought there would be a spot on the concrete.

So, let's just say that the rad and overflow and various hoses are perfectly fine. (I know, not a perfect world, but I like to be prepared.) What internally/externally on the engine could be the issue? Just so that I know what to possibly expect and what I may need to keep an eye out for.

 

I wasn't talking about the bottle being pressurized.
After the car was shut down and pressure built in the radiator- which should overflow to the bottle, right?- coolant was instead being blown onto the rad core and evaporating. Then, as it cooled the leak stopped and the rad would suck the bottle dry.

I doubt that's your problem though (but worth investigating if this continues)...maybe you had some air that finally evacuated and the system sucked up the bottle to fill the vacancy.

Don't always suspect the worst if a simpler explanation will suffice.

 

True, I'll keep on eye out for things. Hopefully it was just some air, though that would have been an awful lot since I made sure that thing was pretty much topped off after I drained and filled it, just for that reason alone.

I do tend to jump to the worst conclusions with this car specifically. Too much sentimental value in it, my grandfather gave it to me back in September before he passed in February and I never got to give him the ride I promised him after I fixed it up.