After blowing a T connector I started looking for "why". I dismissed the water pump (replaced last year). I did find the radiator was restricted. Cleaned and flushed it as well as h-core, changed hoses, thermostat and r-cap. But still running hotter than normal. After driving for about 45 minutes it got hot enough that I had to run heater to keep from overheating. Put sealer in fluid by chance there was a head gasket leak. Checked oil and fluids and did not find any evidence of a gasket leak. However, I did find that when the engine would get hot...that if I stopped, ran the heater, and increased engine rpms that the temp would come down.
?1. could I have a gasket leak and not notice it.
?2. based on the rpm mentioned above, could the w-pump need to be replaced (when I first start the engine I hear a squeek like a dry pulley).
?3. could the radiator still be plugged.
I would really appreciate some advice.
Best regards,

 

I would assume stuck/faulty thermostat ( I've seen a couple thermostats that were bad right out of the box ) or thermostat may have been installed backwards.

 

Thanks BV. I'm sure it is installed correctly...but I never thought about it NOT working out of the box. Will check it out tonight.

 

Get the engine hot and then feel around the radiator. It should be hot all over, cold spots mean it is plugged and needs to be replaced.
Steve

 

BV - thermostat was ok.
SteveR - Radiator had a LARGE cold spot that I could not feel until I removed the shroud. Replaced it over the weekend...temps are now "on the money". Thanks!!!

 

I'm glad it worked out. I have the opposite problem, the temperature gauge almost never goes up unless it is crazy hot. I always thought it was a dash problem but now I suspect I may have a locked-open fail safe thermostat. Not looking forward to pulling it out for a look...
Steve