Ok, I'm not exactly sure how to describe all this, but I'll give it a shot:
1991 Montero, freshly rebuilt 3.0/auto. Runs like a champ, but has now developed some strange behavior with the cooling system. Was driving home and the temp gauge started climbing way out of its normal condition. It did not overheat before I got home.
Opened the hood for a visual and the coolant overflow bottle is bubbling like crazy and spewing out everywhere. Hmmmm. After it cooled down, I checked the level and it was almost a half gallon low. I topped it off, sealed things up, and no more issues, until about a day later, the same thing. Temp is rising, overflow is puking, coolant is low.
This time I checked the radiator immediately after shutting it off and I'm finding cold spots. I got bit by this in my Raider. Ordered a Chinese aluminum radiator(yeah, yeah, I know), swapped it out, changed the cap, and now I'm thinking I've got it all fixed. Wrong!
A couple days go by and I've got temp problems again. This time, coolant is leaking out of hoses that were never leaking previously. Checking the coolant level and again, I'm down about a half gallon each time. I've re-tightened the hose clamps, but then it starts puking out the overflow again.
This morning I do my check/add water routine and as soon as I vent the cap, the bottom tank of the radiator is leaking. This is with the engine cold and obviously no pressure on the system, since the cap is off. Anytime I shut the engine off, I do a quick underhood/under car check and if the overflow isn't overflowing, I don't see any coolant on the ground. If it's going into the engine, it must like running on anti-freeze as there's been no exhaust steam or cylinders mis-firing.
Two more weird things:
1) I have intermittent heat inside. Earlier in the week, I had pulled over to take a phone call(engine still running). I had plenty of heat when I stopped, but as the temperature started to climb, the air from the heater got colder, and then no heat at all as the temp climbed higher. When I drove off, the temp came down and the heat back on.
2) When I open the radiator cap to refill, it smells like exhaust. I am thinking this is not a good thing at all. Seems to me the only thing that could cause this is a cracked head, but the machine shop checked them out and said all was well. I've watched for bubbles with the cap off and the engine running, but I don't see anything unusual.
Any ideas what's causing all this strange behavior? It's certainly not making much sense to me at all. I'm wide open for ideas/suggestions. Thanks!
