Hi, Just did a GSR swap and its overheating and I noticed that
-Top Radiator hose is hot while bottom is cold
-Fan doesn't kick on (when I by pass the Fan cooling switch it kicks on)
so I replaced the cooling fan switch and thermostat assuming that it doesn't open...
still does the same thing.. I've inspected water pump its still spins freely.

What else could cause the problem?? Could any one give me some help?? I was thinking the "TEMPERATURE SWITCH" the one that goes on the head, but wasn't too sure .

 

Sounds like air in the system , bleed the coolant. Also did you use a oem honda thermostat?

 

Yes it's an OEM thermostat , and we did bleed the coolant all bubbles were out.

 

Either the thermostat is sticking or you forgot to fill your overflow, and you don't have enough coolant runnin through there. If that's not the issue you may have a blown head gasket...

 

make sure radiator isnt clogged up, I would be wasting my time right now if you have a new or known good radiator.
But if its old and crusty run the garden hose through the top and bottom tanks along with compressed air.
This has always worked for me if its the radiator.

 

if you see smoke coming out of the radiator then your head gasket is bad, you will know when you lose lots of coolant, and the air bubbles never go away. Overheating is caused by your thermostat

 

Thanks for the replies, the radiator is new, headgasket was also replaced recently (according to previous owner). So I replaced my temp sensor (the one on the head) and the fan cooling switch. Going to try again later to see if fan kicks on when its hot, otherwise I'll try running it with no thermostat.

 

Time to go H2B

 

we have same problem. have si 2000 and gsr swap.
my bottom hoses are cold and top is hot.