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Hi everyone, I’m new to this forum and was hoping you guys could help me with this problem. I love my caddy to death and would hate to have to get rid of it. I was reading some of the forum stickies and saw how you guys like specificity so I'm going to give you the whole story. I apologize for the wall of text in advance.

I have a 1987 Cadillac Brougham 5.0L(307) V8 4 Barrel Carb.

Let me start with the very first signs we had. A couple months ago my radiator leaked out some fluid over night in the driveway. When Ichecked the fluid level it was pretty low. So I filled it back up and checked for leaks, but didn’t see anything. So the next day when I came home I checked for leaks again, but this time when I opened the hood there was a small jet stream shooting out of the front side of the block where the left head meets the block. So I talked to my dad and we discussed Bar's Leak. So I went to the local parts shop and talked to the guy and he gave me some Bar's Leak. We put it in the radiator and the leak disappeared. So, I thought I was free and clear, problem solved.

Well on my way to the theaters a few weeks later I was cruising about 70 just floating down the road if you will,then we came up to the incline in the highway. This incline isn’t very steep, but its noticeable and long. So as expected I start slowing down about 5 mph with the same amount of gas. Now I'm not one to floor it to get it back up to speed I just let her do her own thing and I get there when I get there. That being said my friends weren't as patient as me so I heard a lot of grief. So I drove it harder than I normally would to get to the theaters. This incline is about 10 miles long. Once we arrived steam was pouring out from under my hood. Being a college kid I decided to neglect it and went into the theaters and figured I'd give it time to cool off. After the movie I put more water into the radiator and started the drive home which is down hill now, but about half way home my car starts feeling really sluggish and not very responsive. I thought I was running out of gas. So I pull off and head to the nearest station, but she stall's before I can get there. Once again steam is pouring out from under my hood. (my temp coolant light never came on and the drive home is about 20 mins or so) So me and my friends push her to the gas station and wait it out.(almost 2 hours I'd say) We poured more water in and took the back roads home slowly.

So after accessing the problem and talking with my dad we thought that the thermostat might be bad and not the water pump because it looked new and when we left the car running the bottom, upper radiator hoses were hot and the heatercore hose was hot as well.So waterwas flowing through the pump. Anyway, Iwent and got a thermostat and installed it next day. Let it run with the A/C on andit didn’t look like it was overheating. So I drove it into town(about 5-10 mins) and again it started feeling sluggish, so I pull over and park it and then my temp coolant lightfinally comes on. I opened the hood and the overfill is filling up with boiling water pretty quickly and the water was brown and had a very nauseating smell, like exhaust. So I waited it out once again and drove it home. We decided to park it until we could talk to a mechanic or the Cadillac dealer and see what they thought. Turns out most of the people we asked said the thermostat was a good start, but since that wasn't the problem they thought the next idea would be a blown head gasket.

So me and my dad tested all the compressions and the left bank had two really low ones at 138 and 142. All the rest were about low to mid 150's. So we decided we were going to tear it apart and replace the gasket. For the dealer to do it would be like an easy $1200 is what the mechanic said. I don't have that kind of money and my dad personally wants me to get rid of it, but I can't let that happen. I’m determined to fix my beautiful car.

For the next three months I went threw a learning experience of tearing apart an engine with my dad. We did it all by the shop manual. We get the block all back together with all new gaskets. I even replaced the bottom radiator hose. We may have switched or put some vacuum hoses backwards. Get it all back together with new plugs and the oil changed. Drained the radiator and filled it up with new water. It started up fine, but she was running a little funny, not as quiet as before. We sit there and watched it for about 20 mins. Then the overfill starts filling up with boiling water. Turned it off in disappointment.

We brainstormed some more and decided it's either the radiator, water pump, or a faulty thermostat. So we tested the thermostat in boiling waterand it was fine. Although the water pump looked new I went ahead and bought a new one. We replaced the water pump and started it and looked like she was running fine. Drove her into town and at the gas station the overfill started filling up with boiling water again. Waited it out and drove her home.

So here I sit stumped as to why she is overheating. Only thing left that I know of is either the radiator is bad or the engine is shot and has a cracked block. Any ideas? comments? I really hope you guys can help me, this is my first car and I hope to have it sitting in my garage when I'm 70.