Ok guys i know everyone is sick and tired of seeing another overheating thread but this one might be a lil dif. Possibly cracked CYLINDER HEAD?
Well since it was overheating i decided i need to make sure its fixed so i decided i was gonna put a lil more with it. So i went out got some full race traction bars put the new EG rad in it with new slim fan. Replaced the water pump, thermostat, rad cap, thermo sensor, and throughly cleaned the system. I also did a compression and leak down test. ALL GOOD. Compression was about 270 on all 4 cylinders and and leak down was no more than 8% on all 4 cylinders. I then bleed the system with heat on full blast extremly well about 2 times about 30 min a piece Well i thought this was def going to fix my overheating isssue. WRONG. The bastard still overheating. Its advadently building pressure somewhere becuase it fills the resivor completly up.

My heat only comes out sometimes but when it blows out cold air then it overheats. As soon as the heat blows again it begins to cool down. So obviosuly theres air in the system which causes no heat to come out when the air passes threw the heater core. THATS MY OPINION!!


So to sum it up i cant figure out what the crap is going on. Do you think theres a possible crack in the cylinder head causing air to get into the system? Thats the only thing that can be left. PLEASE HELP!!!!!

THANKS!!!




Modified by doublek at 7:34 PM 7/28/2005

 

How about the head gasket?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GDR888 &raquo;</TD></TR><TR><TD CLASS="quote">How about the head gasket?</TD></TR></TABLE>

Head gasket should be fine since i did the compression test which showed all cylinders at about 270psi. And leak down test was about 8% on all cylinders.

I guess it still a possibility. But highly unlikely. No oil in coolant or visa versa.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doublek &raquo;</TD></TR><TR><TD CLASS="quote">
My heat only comes out sometimes but when it blows out cold air then it overheats. As soon as the heat blows again it begins to cool down. So obviosuly theres air in the system which causes no heat to come out when the air passes threw the heater core. THATS MY OPINION!!
Modified by doublek at 7:34 PM 7/28/2005</TD></TR></TABLE> If it does that, heats blows warm air, and it cools down, then air is cool, it heats up.. it kind of sounds like the thermostat is opening and closing for no apparent reason..

 

Ive also changed the thermostat twice. Becuase i have heard of them being bad right out of the box. I just got the OEM replacement.

 

then.. i'm going to have to say you have a pocket of air in the system..

 

What would be causing that to happen? Besides a cracked cylinder head?

 

someone has to know or have had a this problem.....i cant be the first.....

 

bump

 

run a pressure test on your cooling system-
problem 1 - thermostat-
problem 2 - waterpump
problem 3- air pockets
problem 4-head gasket
problem 5-cracked block( car most likly wouldnt run)

answer it enough check each one in that order and problem will be discovered