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Thermostat testing

  • Thread starter Thread starter Celeb
  • Start date Start date Jan 18, 2010

Celeb

20+ Year Stangneter
Sep 8, 2002
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Jan 18, 2010
#1
  • Jan 18, 2010
  • #1
So after a cam swap, my car starts overheating. With car warm, upper radiator hose as well as lower radiator hose stone cold. Radiator as well, and heat stopped working. (Well it comes and goes) When the heater rarely works, the engine temp cools off but goes back to cold when engine runs hot.

Bench tested the old one and while it opened, it seems to barely open, maybe 1/8". New one opened almost twice that.

Haven't cranked the car yet, waiting for some permatex to dry. Probable culpret though based on the symptoms?
 

timeless2

Vi Veri Veni Versum Vicus Vici
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Nov 29, 1999
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Jan 18, 2010
#2
  • Jan 18, 2010
  • #2
No heating issues whatsoever prior to the cam swap?
 

Celeb

20+ Year Stangneter
Sep 8, 2002
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Jan 18, 2010
#3
  • Jan 18, 2010
  • #3
timeless2 said:
No heating issues whatsoever prior to the cam swap?
Click to expand...

Nope, heater worked fine and engine remained cool. Perhaps some type of debris made it's way to the tstat while I had the engine open (scraping off old gaskets etc) Installed a new water pump as well. Old one worked but it made an awful racket.
 

timeless2

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#4
  • Jan 18, 2010
  • #4
Next, check for air in the system. Burp time.
 

Celeb

20+ Year Stangneter
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#5
  • Jan 18, 2010
  • #5
Hopefully the new tstat fixes it. If not I'm worried that my new water pump isn't moving water. I'm wondering if there's a bench test for that. Maybe pull the smaller hoses off the top of the pump and get someone to bump the engine?

Good call on burping the system also.
 

timeless2

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#6
  • Jan 18, 2010
  • #6
T-stat is an easy, cheap fix...if it's truly the culprit. Rule out those really easy ones first, then go from there.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jan 18, 2010
#7
  • Jan 18, 2010
  • #7
If you don't have one, a burping funnel makes burping the system a little easier and a smidge safer. I always run the cars for a bit with no rad cap installed (this is where the funnel can help). Otherwise the buried air has a tough time surfacing.......

I also like Tim's thoughts on the stat. FWIW, air in the system can damage the pellet (especially true on a non-balanced stat). That could be another reason the old one went south.

Good luck bud.
 
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