Ok, I drive a 96 ex turbo (8-10psi) and just a few days ago it started to overheat and boil over.

When I press the gas to full throttle the coolant will flow into the reservoir until it starts to overflow. What would cause this to happen? I don't know what else to try...

I have already:

-Replaced thermostat twice.
-Replaced the single core radiator with a dual core.
-New water pump.
-Back flushed the coolant system.

I don't know what else it could be... The car does not smoke at all under full throttle/full boost so the head gasket is not blown, and I do not think the head is warped...

Somebody help me!
Thanks

 

smoke or not, sounds like a head gasket

 

Thanks,
I will check my compression tomorrow...

I don't see how it could be the head gasket though, there is no sludge in the radiator, there is no smoke in the exhaust, how could that happen?

 

My crx did the same thing under boost. I read some place that the d series heads lift under boost.
I finally ended up rebuilding my motor and using arp head studs, A little extreme of a fix, but it hasn't done it since

 

Well I am not really trying to rebuild the motor because its my daily and that would take it off the road for too long. But I will change the head gasket and I just bought some arp's. If this does not fix the problem I guess I will just swap the whole motor out...
Thanks

 

I bet you got air in your cooling system. Also test the thermostat.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B16aDasher &raquo;</TD></TR><TR><TD CLASS="quote">I bet you got air in your cooling system. Also test the thermostat.</TD></TR></TABLE>
Not sure about that. mine did the same thing. I blead the system countless times

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by yellowrexsi &raquo;</TD></TR><TR><TD CLASS="quote">Not sure about that. mine did the same thing. I blead the system countless times</TD></TR></TABLE>
Just throwing it out there. My car did the same thing. It was air in the system.

 

Good point and info. I over look the simple stuff sometimes

 

Unfortunately my car does not have a bleeder valve.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CivicManLs &raquo;</TD></TR><TR><TD CLASS="quote">Unfortunately my car does not have a bleeder valve. </TD></TR></TABLE>
?? you can remove the air without a bleeder valve.

 

I would suspect that the system is self-bleeding?
I am not sure if they changed that in 96 but I am about to swap the upper radiator hose housing with one from a 92-95 just for the bleeder valve.

 

I checked my compression today...

cyl. no 1-4 are at 180, 185, 190, 190 in that order.

I believe the head is lifting under higher boost (above 7psi), how would I be able to tell? I will re-torque my head bolts and make sure they are all at the same tq.

The head has never been removed before and I don't really see how it could be warped since I never let the car run if the needle gets too close to the red H line...

 

yeah true...but if it is the head...just have it shaved...not too costly and it'll save you some headache.

 

I have a built z6 head that I will be swapping in place of my stock y8. I ordered ARP head studs, I was told to order them for the head that I will be using, in this case the z6... Is that correct?

 

It could be air in the system or the wrong antifreez to water mixture. since the car is under boost i would up jump the antifreeze in order to lower the bloiling point of the coolant in your car

 

I use pre-mixed 50/50. The car does not overheat unless I floor it and the boost psi goes up above around 5psi. I can drive as far as I want without having to worry about overheating but as soon as I hit boost all the water rushes into the overflow and the car will start to overheat...