Hello all,

I'm brand new to the board, which I feel fortunate to have discovered, but unfortunately it's as a result of a recent run-in with dealership service. First I'll intro with a bit about myself and my ride. Please feel free to skip to the part labeled "mechanical breakdown" in bold towards the bottom if you don't need the background info.

I live in Phoenix, AZ which means this Blazer and I have endured 116+degF routinely over the course of the last summer. Humidity here fluctuates between about 10 and 40 percent. I handle this vehicle with care and consider myself mechanically savvy. How savvy is up for debate *lol* but I have rebuilt both '66 Dodge Dart and VW Bug engines from the split cases up. My Blazer is from Colorado and shows minor (read surface) signs of rust on the lower exposed framework. It is a white, 4dr/4wd, with 125k miles, and no mechanical problems other than routine wear and tear like some soft rear shocks etc.. I am the third owner and I bought the car 5k miles ago. The second owner purchased the vehicle at 102k miles from a dealership. He was not very mechanically aware but did handle the vehicle gingerly.

Okay so now that you know the two of us lets begin with my nightmare. The heat here during the summer contributes to a debilitating medical condition. As such I have to work on this car from 4AM to 7AM when the temperature momentarily drops below 90. I've even let my poor Blazer go a month past her oil change due date as a result. I finally caved when I found a local Chevy dealership in Glendale doing a $8.88 oil change special. I handed them a working Blazer and what they handed me back left me stranded on the side of the road 2 hours later. She overheats within 1 mile of driving now, pinning the temp gauge at 260, and sets off the check gauge warning light. Long story short: They won't fix it, I'm unable to work, and I have little cash reserves at this point. I have reported to the Attorney General, BBB, Media, GE Motors, and the dealership's management.

Looks like its up to the kind folks on Blazer Forum to set straight some karmic injustice. I know that I could figure this out on my own given good health and an abundance of money. I need suggestions to make the labor and cost as "un-impactful" as possible. Please try to keep in mind my responses and work times will be slow. Apologies to all ahead of time.



Mechanical breakdown:
The vehicle starts fine and runs normal for the first mile.
The temp will run up to 260degF triggering the dash warning.
Sometimes at this point the temperature rapidly returns to a "normal" 210degF. If it does not I try to shut down the engine w/i 60secs.

There is either coolant or A/C discharge leaking on the driveway but it is not noticeably depleting the reserve tank. The dealership claims there was evidence of a leak before they began their work. There is a faint coolant smell when she gets hot. There is no coolant in the exhaust.

A film is beginning to form on the inside of the windshield that leaves it looking permanently foggy until I wipe it off.

When the A/C is not turned on while driving there is an immense amount of heat coming into the cab. This gets hot enough to burn your feet with sandles on.



My personal diagnosis:
There may be a hose, pump, or gasket leak but I don't think this explains the rapid degradation in cooling performance w.o a large loss of fluid.

There may be a "sticky" thermostat. This troubles me as sticky and engine are not words I care to hear in the same sentence. If this turns out to be true I'm worried about what may have happened to my heater core, radiator, hoses, and block cooling passages.

There may be a heater core or attached hose leak. This explains the film on the windshield according to several threads I've read.



Standard response:
The standard response to overheating is to replace thermostat, temp sensor, radiator cap, check for air in the system, try again, then look much harder for leaks and obstructions to be handled accordingly. I do NOT have the money to guess on even a single part, nor will I likely be able to purchase tools. I do have access to a decent array of tools and materials so I may be able to rig some things up. I also do NOT have the good health or extra hours required to dig around endlessly disassembling and reassembling this engine.

Any advice that may help me to get this fixed in an efficient manner would be greatly appreciated.

Good meetin' ya'll!

 

well if u think its the thermostat take it out and boil some water and see if it opens up. are you loosing any coolant from anywhere if not how sure are you that maybe the coolant sensor hasn't gone bad. lots of what ifs.

also as far as the dealership paying for something they never touched your screwed. they did an oil change so they didn't touch a/c or coolant thus making this problem all yours which is why they wont pay. you made it out the shop and driving 2 hours or so means it could be very random coincidence but not their fault. I'm not trying to sound mean but from an outsider looking in you have no case in that.

 

Thanks for your reply Lune.
On the legitimacy of this case: It wasn't driven FOR two hours it was driven IN two hours. It took them two hours to provide a $8 oil change. The vehicle broke down within two miles of them handing me the keys. I had to go one mile at a time with 30 min cool down periods just to make it home. But not before they told me what to do with myself and my problems...
The thermostat is of course one of the first things I am planning to check, however, I'm trying to develop a full game plan with cost and time analysis before I even begin taking things apart. (Did I mention I'm in college for engineering *lol*) This approach is necessitated by my lack of funding and poor health.

 

Best I can tell your is thermostat, from your description of the "jumping" temp and you will definitely need to replace the heater core. Neither part is expensive, considering. The thermostat is simple to change, the heater core is not. You can bypass the heater core easily until temps cool down. Simply pull the hoses off at the fire wall and insert an elbow between them. Keep in mind the hoses are different sizes and you'll need an elbow to match.

 

Yes thermostat and heater core i'm sure of from reading your description.

Things to look for as far as your coolant leak. 1 check the weep hole on the water pump. 2 make sure all hoses are tight and not cracked or dripping at seals. 3. if all else fails get you a little flashlight and check the front and rear of the engine as well as the valleys around the valve cover/ intake manifold areas for any wetness. (Lower intake manifold gaskets are a common failure on these vehicles but check other areas first). Another common failure point is the plastic end caps on the radiator, where the upper radiator hose attatches to the radiator check around it and on the opposite side (toward the radiator support on the front of the truck) for cracks.

Obviously what you check depends on WHERE the puddle is forming. I'd replace that thermostat and heater core first though.

 

I had the same problem and it turned out to be a blown head gasket. had to tear down the engine and get the heads cleaned and refurbished. Now Im having problems witht the timing and the battery cables keep getting hot and draing the battery down to nothing.