Hi
I'll start by saying I know nothing about car maintainence. Today I opened the hood for the first time since taking delivery three and a half months ago. The coolant tank shows a half an inch above the minimum level mark. So I opened it and tried to add some more coolant, but when I opened it, some spilled out and it was actually full to the top.
My question is how come the tank shows minimum level when it is actually full? Am I doing anything wrong?

I'm assuming you mean coolant reservoir when you say coolant tank?

If so, you're fine as long as it's above the bottom line (i.e. between the full and low lines). Coolant expands when it's warmed up, so the coolant in the reservoir will keep the radiator full.

Now, if it falls below the line or after you top it off, then that means there's a leak somewhere (i.e. the hose between the reservoir and radiator may be loose or damaged, the pressure cap may be faulty, or there may be a leak elsewhere).

Oh, and when did you check the coolant level? Was the engine cool or was it still warm? Because that might be the reason why coolant spilled out.

Thanks for the quick reply.
I checked it when the engine is cool, but it was 4pm and it was like 90F and sunny, (couldn't get away from that, I have no garage). Would outside temperature have any effect on that?

The outside temp(90F) shouldn't affect the level when the engine is cool.

More importantly what kind of coolant did you top off with???

When the engine is cold, its OK for the level to be near the MIN mark. As engine is run, temps and pressures increase forcing some coolant out of the engine. The excess goes into the reservoir tank. You have to leave space in there for these conditions which are part of the normal operating process.

When the engine is cold, see if you can't remove some of the coolant from the tank to bring it near the MIN mark again. The tank should lift straight up.

Please dispose of the coolant safely. You can put it in a small water bottle and drop it off at a recycling center. (Many Walmart locations offer this.)

On a related note, what kind of coolant do you use when you topped it off? I highly recommend sticking with Honda's own undiluted coolant.