over heating b/c of thermostatt?

[felskee]

okay. we replaced the heads. then when we put the thermostat in it over heats? i bought a 2 core rad insted of the single. and it works well,when theres no thermostat. when its in there it heats close to 260. i dont understand. please help.

 

[SunlitComet]

Didn't we already see this movie?

Is your water pump function and ports fully up to par or perhaps you have a severe blockage somewhere in the bypass passages/hoses or intake manifold?

 

[felskee]

im not sure. how would you check this

 

[SunlitComet]

By taking it apart and inspecting pump impeller and every passage you can for the pump and manifold. I boroscope would be helpful too.

 

[felskee]

okay, so theres no possible way its because of the thermostat(s)?

 

[SunlitComet]

I can't see several different thermostat failing every time unless it is the wrong part. Post your vehicle info and a picture of the ones you have been using if you can.

 

[felskee]

1999 tahoe 5.7. and i think its this one.http://shop.advanceautoparts.com/we...-P_133_R|GRPCOOLAMS_1715285105____#fragment-2
or this one.
http://shop.advanceautoparts.com/we...ant_5650076-P_133_R|GRPCOOLAMS_1698590574____

ill get the real pictures inna tommarow.

 

[Chevyrider619]

Why are you putting a 195? it's summerrrrput a lower thermostat man..

 

[SunlitComet]

Looks correct. But if your pump, passages and fan clutch can't keep up it won't matter. If you are overheating it does not matter what temp you use. Something else is seriously wrong that needs addressing such as the inability a fan to cool it down or motive flow to move the heat.

 

[felskee]

but it works perfectly w/o the thermo. and when i first put it in it stayed cool. barly reading on the gauge. i watched it for bout 20 mins. stayed the same. left it a little longer it went to 260.