Freshly built b16a2 is overheating after 5-10 mins at idle and its driving me crazy... Ive bled the system by starting the car with the radiator cap off and adding coolant as needed, once it gets hot coolant gushes out the top. The fan doesnt kick on, the bottom hose stays COLD, and the heater blows cold. Ive jumped the ECT connector to make the fan stay on and it still overheats.
The thermostat is new and so is the water pump. I was told the radiator could be clogged since its been sitting for 2 months for the engine build. But i can squeeze the bottom hose and coolant will come out the water neck.

Another thing could be the headgasket(new) or warpage, 185 psi across all 4 cylinders, no coolant in the oil or vice versa. So im thinking its not that.

I thought i had the bypass hose(U shaped hose) and heater hose switched but one is bigger than the other so unless im stupid i think they are right. If anyone has a pic i would greatly appreciate it.

 

So burped the system and wired up the fan to stay on all the time so that eliminates the air in the system and a bad relay or thermoswitch.

I would flush the system out to check for clogs. Also, are there any leaks?

Open up your overflow tank, is there a black film inside?

 

Temporarily remove the thermostat - see if that helps (I know you said it was "new") - just temporarily remove it.

Also, make sure your CTS (coolant temperature sensor) is reading normal values.

Temporarily I'd do what 95ProjectEJ1 said, hardwire it to the battery or just buypass the switch.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Syndacate &raquo;</TD></TR><TR><TD CLASS="quote">Temporarily remove the thermostat - see if that helps (I know you said it was "new") - just temporarily remove it.

Also, make sure your CTS (coolant temperature sensor) is reading normal values.

Temporarily I'd do what 95ProjectEJ1 said, hardwire it to the battery or just buypass the switch.</TD></TR></TABLE>
I would agree with this. It sound like you have a bad termo or its in backwards... I don't even know if that is posable on these engines but I have seen it done on Chevy's and Ford's before

 

The onl issues I ever had with an oem t-stat was the rubber gasket was somewhat loose and didnt fit snug around the t-stat. Then again I am a dumbass sometimes and possibly didnt install it correctly.

With all the grounds the op covered I think those are his only options...

bad tstat
possibly clog *shrugs*

Compression seems fine, but who knows

 

I really appreciate all the help ... I know the thermostat is installed correctly with the pin up, im going to remove it today and see if that is the problem. If that doesnt solve anything im going flush the radiator and pressure test the system.

And there is no sign of any leaks.

 

Yeah, flush and pressure test the system. If you can, look into the thermoswitch and relay. If you need to know how to test them let me know, you could eventually just wire it back to normal and run the fan off the thermoswitch.

 

The thermoswitch, you talking about the ECT thats on the thermostat housing?

 

Yeah, you can unplug the connector and run a paperclip fron one port to the other on the female side. That will engage the relay and activate the fan if its working.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95ProjectEJ1 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, you can unplug the connector and run a paperclip fron one port to the other on the female side. That will engage the relay and activate the fan if its working. </TD></TR></TABLE>

Ok, yeah i did that and it still overheated so i know the relay is good.

 

All the ^^ above post will do is let you know that your thermoswitch and relay are good. If the thermoswitch never sends the signal the relay and fan will not be able to do their job. If you did the paperclip trick and the fan didnt come on then one of the problems is the bad switch

 

Yeah, im not sure if the ECT is good or not because the lower hose isnt even getting hot which means hot coolant isnt reaching the the ECT to activate the fan. I could take it out and measure resistance.

Went to autozone to rent the pressure tester and none of the damn adapters fit Guess ill move on to removing the thermostat, such a pain in the *** removing the vortech aftercooler just for that.

 

They finally found an adapter i could rig to make work. Found a pin hole in the upper radiator hose. Could this be the culprit?

 

That could cause a small small leak and a loss in pressure I would imagine.

 

I hope its the problem, i figured it would leak before anything.

 

I replaced the upper hose, and it still overheated. After alot of swearing and cold bud light. I took the aftercooler off, popped the brand new autozone thermostat out and ran the car without one. No overheating, the fan kicked on, and i got lots of heat. Needless to say im going to honda tomorrow to pick up a t-stat.

Autozone thermostats FTL

 

damn no wonder they give lifetime warranty on everything, its all crap.

 

Tstat FTW! If your lower hose isnt heating up then your tstat isnt opening up. You could test the "new one" by boiling it in water. It should open up around 190. If it doesnt then theres the problem. The fan will not kick in because the tsat hasnt opened thus not allowing the ect to see 190 and thus overheating the vehicle due to no fan operation. Replace,bleed and drink a beer