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Cooling issues (kinda long)

  • Thread starter Thread starter Lyonmt
  • Start date Start date Aug 23, 2007

Lyonmt

Member
Nov 17, 2004
110
7
18
Tampa, FL
Aug 23, 2007
#1
  • Aug 23, 2007
  • #1
It all started last week. The serpentine belt cut through my lower radiator hose. After replacing the hose, I put a gallon of coolant and what seemed like about two gallons of water into the radiator. Since then my temp has been all over the place and I keep losing coolant. Two days later, I added coolant. Then I didn’t drive it over the weekend and on Monday it wouldn’t start when I got home from work (I suspect it was heat soak), however it started later that evening and has started every time since. I added coolant and let the car run with the cap off. Some coolant came out and I added a lot more. The next day the temps were up and down again. So I bought a flex fan. I couldn’t get the flex fan installed, because of interference issues with the fan shroud. The next day was the same thing, temps all over the place. I drove home without the A/C and the temperatures were stable, but when I turned on the A/C, it got hot in a few minutes. When I got home, I installed the flex fan and beat up on the car a little for testing purposes. It mostly stayed cool, but went up a little bit at one point. I also found that the oil was a quart low, as I seem to have a valve cover gasket leak. I added the necessary quart of oil. Today it is all over the place again. So I picked up a thermostat and more coolant. I don’t see any coolant coming from the heads. When I got back from lunch, the temp gauge read about 210 or so, but when I opened the hood and touched the cap it was warm, not hot. So I flipped the lever on the radiator cap and nothing vented. I then removed the cap and the fluid looked about a half gallon low in the radiator.

When I say “all over the place”, I mean the temp starts off pretty stable at around 195 and then when accelerating, the temp will sometimes go up to about 210 and then slowly drop down as I maintain cruising speed. Sometimes it will start to climb while sitting at a traffic light. Sometimes it will go down at a traffic light. It will usually go up when the A/C is on. Usually it will level off or go down very slowly at cruising speeds.

I plan on replacing the thermostat with a 180 degree unit, not before I drill a small hole, so that it can burp itself.

Any thoughts, suggestions or help would be appreciated.
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Aug 23, 2007
#2
  • Aug 23, 2007
  • #2
How long did you let the engine run with the radiator cap off. You may still have air packets stuck in the system. I would run it with the cap off until it comes up to operating temperature that way the thermostat opens and can burp out all of the trapped air. As far as replacing the thermostat with a 180* stat, i'd make sure you found all of the issues. Changing to a lower stat might just cover up a real issue.
 
F

Fox8950

Member
Jun 29, 2007
247
2
18
Aug 23, 2007
#3
  • Aug 23, 2007
  • #3
I agree, I had that same problem just because of a few air pockets I failed to get out in the garage. Popped off my radiator cap to find it a gallon or so low more than once. Hopefully its that simple for ya, besides if it was leakin or burning THAT much fluid you'd see it or smell it.
 

Lyonmt

Member
Nov 17, 2004
110
7
18
Tampa, FL
Aug 23, 2007
#4
  • Aug 23, 2007
  • #4
I changed the t-stat (drilled a small hole in it first), replaced the bypass hose that ripped in half when I took it out and let it run until it hit operating temp. The problem persists. Next is the water pump and then a radiator if it continues...
 
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