Coolant mysteriously disapearing
My name is Brett and I live in Ann Arbor, MI. I am new to this forum, so please be kind. I just recently, back in December, purchased a 2001 Disco II (69,128 miles) to replace my aging RRC. It now has 70,139 miles.
Up until a week ago, everything has been great. I was driving to work one morning (~3 miles), and never got any heat. Just as i turned into my parking lot, i noticed the temperature gauge started to rise above where it usually sits. Which seems to be just slightly over half way. It never got outside of the normal range. After work, I drove home with the same results. Temperature gauge starting to rise just as i got home. I let the engine cool then went to check things out. I determined that it was about 1/2 gallon low on coolant. This was not the case when i bought it. I topped it off, started it up, and everything was back to normal. The question is, where did the coolant go? It doesn't seem to make any puddles on the ground.
After scouring the web and reading through posts on this forum and others, it seems that it is not uncommon to need a head gasket replacement at 70k miles. With this in mind, i wanted to be sure this was the problem before conceding that I need to do such an undertaking. I took it to a local shop, and mentioned that I suspect a head gasket leak and I would like it checked out. They checked it out saying that it would need a new radiator, new intake manifold gasket, and new timing chain gasket for the cost of $3300. The mechanic mentioned that he had no reason to suspect the head gasket. For the most part I felt this as good news, since I could just top off the fluids from time to time and i should be able make it to warmer weather to start some of these repairs myself.
However, I have a very concerning feeling that the head gasket still may be at fault. One reason is that the oil cap has an awful lot of water/condensation in it. The oil cap also seems to require herculean strength to remove when the engine is warm. I have since put in on barely tightening it. The surface of the inside of the oil filler tube seems to be a chocolate brown. I don't smell anything out of the ordinary, but i also have a cold, and can't smell much of anything. Another reason is, since the temperature rose that one morning, I have been inspecting it almost every day. It is usually about 1/2" below the normal line on the tank. I usually fill it to the cold line and go about my day. It just seems to be consuming a bit too much coolant to be leaking it without noticing any puddles ever.
Later today I plan on changing the oil and see how that looks, I will take pictures in case i may need to post them.
My main question is, am i being a bit too concerned about the head gasket, or should i go with what the mechanic said? Any help, info, helpful criticism is most appreciated.
Sorry about the lengthy first post.
2001 Discovery II
1993 RRC <for sale if interested>
Ann Arbor, MI