Ok heres the background:

- JDM B16a2
- 1 piece thin head gasket
- Its in a 96 civic coupe
- Stock radiator
- The radiator cap is replaced


Why would it be overheating all the time? Its not excessive, but it barely overheats....

 

Leak in the coolant system? How's your coolant level? Air in the coolant system?

Try flushing the system and refilling/rebleeding it.

 

You're not losing any coolant, are you?

 

no, the coolant isn't going away. What happens (forgot to mention this) is that when he pours in the coolant, most of it goes straight to the overflow. We dont think that there is so much in there that it would need to go to the overflow.

 

So you're not *losing* any coolant, but it's getting displaced out of the ratiator and into the reservoir? Sounds like a blown or non-sealing headgasket to me.

 

Holy **** are you serious?? I am experiencing the exact same problems!! What the hell??? Is there anything else that could be causing this and if not, WHY would it be the head gasket? Thanks

 

If the ehadgasket isn't sealing, compression from the cylinder(s) will leak into the cooling jacket. Since the cooling system is sealed, that extra pressure has nowhere to go, but past the radiator cap and into the reservoir. If that happens for a long enough time, it'll displace enough coolant to the point where your engine isn't sufficiently cooled, and it overheats.

 

Insyral, that is EXactly what happens... then the resevoir OVERFLOWS! Also, when i go to dump the resevoir, there is milky browish-black sludgy stuff at the bottom of the tank. Could this be oil leaking into the coolant?? help please! The car is about to go to Daytona and i need to be able to drive it back to Atlanta....

 

That could be oil mixing with your coolant. Sometimes if you let the engine idle with the radiator cap off, you can see bubbles in the coolant, but not always. You could try a compression test, but when my headgasket was blown, my compression numbers were fine, and my reservoir only overflowed when i boosted.

 

yeah the car actually runs pretty well! Pulls just fine... ive just noticed coolant leaking in the car (floorboard) also.. could that be related to the pressure buildup maybe?