Coolant/Oil Question, long post. Knowledgeable people please

I changed my oil today after I returned from an hour and half highway trip and found a couple things that I didn't quite like/understand. The car is a '98 camry 4cyl 2.2 auto, with 75k miles on it, or 130 000 kilometers

First off I lift the hood, no coolant in the tank. I check my fluids once a week and this car never drank any coolant, pretty much always at the Full mark. The car had been sitting for half an hour so I remove the radiator cap and sure enough it's full of green so I say no big deal I'll buy some tomorrow and fill the tank cause I only have Toyota red and they gel up when they mix. What exactly does that tank do? Why would it be empty all of a sudden after a highway trip, while when I'm city driving during weekdays the tank is always full? The radiator was full however.

Proceed to change my oil, then I notice little crystals in the funnel I use to recover the oil after it's done dripping. They look like they might be white or transparent. I had been running seafoam in the gas for this trip to clean up the injectors, but is it possible that gunk or crap got all the way down to the block and oil pan?

Needed gasoline so I drove to the gas station, the car got to normal operating temp, no overheating. When I got there I looked under the hood and there was now a little bit of coolant in the tank, didn't remove the cap obviously.

Drove back home and decided to take a better look. Got the car to idle for about 10 minutes in the driveway while I look and it seemed like there was very faint smoke coming from the bottom of the fans sometimes but I couldn't pin point where it was coming from, and there was some snow and ice accumulated there, so I cleaned that up.

Then realized that after ten minutes, the fans hadn't come on once, but then again it's winter so I don't know what to think. the oil didn't look milky

Can it happen sometimes that the coolant tank is empty, but the rad is full?

This is just a guess, but it sounds like you have a small coolant leak at the bottom of the radiator or the lower radiator hose. It's very hard to be certain without actually being there in person to observe what is happening, especially since you mentioned there was some snow and ice down there. What I would do is fill the radiator and overflow tank with a 50/50 mix of antifreeze and water, when the engine is cold. Observe the level of both for the next week or so. Always check when the engine is cold. If it goes down again, then you are leaking coolant from somewhere. If that is the case and you can't see the leak yourself, I would take the car to a professional who can use a device in place of the radiator cap to presurize the system and find the source of the leak. Some techs will put some dye in the cooling system, run the car for 15 or 20 minutes, and then look for the leak with an ultraviolet light. The dye will show up under ultraviolet light. Once the source of the leak is determined, you can decide on whether you would like to have the tech repair it, or try to do it yourself.

As far as the fans not coming on, you may have to let the car idle when warm for some time until the fans come on. Take a drive to warm up the car and then let it idle in the driveway for up to 30 minutes. Carefully observe the temperature gage on the dash to make sure the car does not overheat. 1 fan should eventually come on. Did the fans ever come on? You can make sure the fans themselves work by turning on the A/C. When the A/C is on, both fans should come on automatically. Remember, this is a different system then the one that turns the fans on from engine temperature; turning on the A/C is just to make sure that both fans operate.

I can't say about the crystals you found, since I have never used Seafoam. Maybe someone else who has used Seafoam can comment on that.

Mike

Thanks a lot, I'm going for a coolant flush tomorrow morning, I'll keep an eye on that. I'll try the AC method too to be sure the fans actually run