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strange acting thermostat

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  #11  
Old 01-28-2008, 08:47 PM
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Default RE: strange acting thermostat

No, not while its running, all the antifreeze will squirt on the ground, Remove the radiator cap and start the truck up and see if there are bubbles in the radiator. If there is let the thermostat cycle a few times and if their is air in the system, THe radiator will kindamake aburp noise and you will have to put more coolant in the radiator
 
  #12  
Old 01-28-2008, 08:50 PM
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Default RE: strange acting thermostat

I have never experienced this problem but have heard about it. I was told that it is caused by a pocket of air that is stuck under your thermostat. The fix for that is to buy a thermostat with a bleed-by hole or just drill one in it yourself(old school).
 
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Old 01-28-2008, 08:56 PM
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Default RE: strange acting thermostat

well, nothing obvious is jumping out at me, and it sounds like you know what you're doing
new rad, 2 new therm, 1 new temp sending unit, and new hoses.
the only thing not new is the water pump, right ?

it shouldn't do what its doing.

sorry, shotgunning a bunch of questions..
1. sorry, i have to ask.. you are installing the t-stat sensor down, inside the manifold right ?
2. and you install t-stat first, down inside the little dimple in the manifold, and then the gasket on top of that, right ?
3. any sloshing sounds behind the dash. air can disrupt things.
4. rad overflow tank full up to min or max.
5. rad cap all the way on good and tight.
6. no leaks anywhere.
7. both new t-stats have acted exactly the same right?
8. what did the original t-stat do ?
9. how old is water pump ?
10. does wp feel ok ? no play, no slop, no leaks, no rattle.
11. did it appear to overheat and act this same way with the orig temp sensor, or is this one unique ? if its unique, i quess it could be bad, if it acts the same as the old one, then i doubt it.
12. have you still got t-stat #1 or #2. test them in a pot of water on the stove with a meat thermometer. see where they 'begin' to open and where they are 'full' open. this is usually only about 5-10* apart at the most.
13. does it act the same way sitting in the driveway as it does driving down the road.
14. when starting up cold, how long does it take the temp gauge to get up to about 190.
15. when it hits about 190, does the top rad hose get warm fast, like there is water flowing, or does it remain cold until temp hits 230-240.
 
  #14  
Old 01-28-2008, 11:35 PM
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Default RE: strange acting thermostat



sorry, shotgunning a bunch of questions..
1. sorry, i have to ask.. you are installing the t-stat sensor down, inside the manifold right ?

the sensor i broke i unscrewed out of the manifold near the thermostat and the heater hose. i just screwed in the new one and plugged it in.

2. and you install t-stat first, down inside the little dimple in the manifold, and then the gasket on top of that, right ?

i did put the TS in first and then the gasket.

3. any sloshing sounds behind the dash. air can disrupt things.

i do have the gurgling near the core but now my heat works again even with it.

4. rad overflow tank full up to min or max.

it's up to max now.

5. rad cap all the way on good and tight.

that's another thing i replaced. new cap.

6. no leaks anywhere.

i seem to smell antifreeze (under hood, not in cab) but i can't find a leak. i'm hoping it's just burning off some i spilled.

7. both new t-stats have acted exactly the same right?

they both did exactly the same thing.

8. what did the original t-stat do ?

it acted normal. it went up about 200 and just stayed there.

9. how old is water pump ?

less than a year. the old one started to leak i swapped it out.

10. does wp feel ok ? no play, no slop, no leaks, no rattle.

haven't checked it.

11. did it appear to overheat and act this same way with the orig temp sensor, or is this one unique ? if its unique, i quess it could be bad, if it acts the same as the old one, then i doubt it.

these problems started with this most recent work which included the new TS and the new sensor.

13. does it act the same way sitting in the driveway as it does driving down the road.

same thing

14. when starting up cold, how long does it take the temp gauge to get up to about 190.

oh it takes a couple miles of city driving i guess. it seems like a normal time. but then it just keeps going up to 240 until it comes back down to 210. freaks me out everytime.

15. when it hits about 190, does the top rad hose get warm fast, like there is water flowing, or does it remain cold until temp hits 230-240.

i will check that. good tip.

thank you for your help.
 
  #15  
Old 01-29-2008, 12:30 AM
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Default RE: strange acting thermostat

ORIGINAL: greenmachine

I have never experienced this problem but have heard about it. I was told that it is caused by a pocket of air that is stuck under your thermostat. The fix for that is to buy a thermostat with a bleed-by hole or just drill one in it yourself(old school).
Thats a common misconseption. That will only take air out of the engine block while the thermostat is closed. Once it is open the air will leave. Either way, its going to warm up and open.

The reason air needs to be "burped" out of the system is that water (or antifreeze) has a cooling capicity 13 times greater than air (13:1) It doesnt take Einstine to see why that would be an issue.

ORIGINAL: danm9




4. rad overflow tank full up to min or max.

it's up to max now.
Dont worry about the overflow tank....how about the radiator? When you start the truck, look in the radiator with the cap off. Is fluid level at where the cap screws on, or can you see down into the radiator a tad? Make sure that is filled (once the truck gets to temp especially)

 
  #16  
Old 01-29-2008, 06:22 PM
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Default RE: strange acting thermostat

so does burping only involve running the truck without the cap for awhile? and topping it off as i bubbles? sounds easy enough.
 
  #17  
Old 01-29-2008, 10:48 PM
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Default RE: strange acting thermostat

yes.
the only reason you want to have the overflow tank between min and max is that if it does push out some pressure, and then sucks it back in when cool, you want it to suck in some coolant instead of air from an empty tank. i had a little air trapped last year with the heater gurgling sound, and as it worked itself out, the level in the overflow tank dropped a little each day.

hey, sorry, but i got to ask one more time, when you installed the t-stat did you put the copper colored sensor thing down, so the little round dome was pointed up. i hate to say it but the initial overheat sounds like something that would happen if the t-stat was upside down.

did you try feeling the top rad hose when temp gauge hits about 190. should get real hot if t-stat is opening up.
 
  #18  
Old 01-29-2008, 11:46 PM
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Default RE: strange acting thermostat

i knew someone would ask so i took a picture while i did it. i think it's in correctly. i hope the pictures shows up.

[IMG]local://upfiles/82448/480F489EC7794D6FA3ED50464238FE43.jpg[/IMG]

[IMG]local://upfiles/82448/B342CBD86D5147198B256024B743DC10.jpg[/IMG]
 
  #19  
Old 01-29-2008, 11:49 PM
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Default RE: strange acting thermostat

i haven't had a chance to check when the hose gets hot. i'll try tomorrow.
 
  #20  
Old 01-30-2008, 12:08 AM
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Default RE: strange acting thermostat

installed correctly.
 


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