My wife drives a 91 Accord Wagon that I have had more than a few issues with since we bought about a year ago. I am not sure, but I believe it may have been in water for a short period of time, due to died mud I found in several places it should have been.

I had a very puzzling problem this last summer with it overheating, which caused two hosed to burst, and eventually found that the elbow tube going into the overflow bottle was melted shut. After fixing that, no more overheating - life is good, right?

But, it is still losing coolant somewhere. I don't smell it anymore, like I did when it was overheating, and I don't see any tell tale signs of overflow or leaking on the engine or hoses. The only thing I can think of is that there is an head gasket leak and it is going into one of the cylinders and burning off. But, it is happening so gradually, and there is no overheating like you would expect with a leak, that I am baffled on how to troubleshoot this further.

Anyone with experience with a problem like this, I would appreciate your advice.

 

When the engine is warmed up sniff the exhaust, coolant will have a 'sweet' sort of smell.
Do not take big gianthuffs of it, carbon monoxide can damage brain cells; I am living proof
Another thing you can do is to run the engine to operating temp, this pressurizes the coolant system, then let it sit for 15-20 minutes. Remove the spark plugs and use a strong flashlight to look down into the pistons.

As far as underhood leaks, again, sniff around the engine when hot, and look for small white tracks[underside of hoses]where the coolant has evaporated from heat.