I have been having coolant issues now since december and have been all over s2ki looking for a solution. First let me describe my modifications after blowing my engine up with a little to much nos( im not going to post the whole story it is way to long) i had the engine sent to my local shop and they ended up sending the block off to get sleaved. at the same time i decided to add an aem standalone, low compression cp pistons, inline pro rods, and clutch and flywheel. after 6 months of not being able to drive my baby i finally had it up and running. The car ran great for a year and suddenly started to overheat the following winter. I was lazy and took the car to my local shop where they diagnosed it as a thermostat issue.
Unfortunetly one of the downfalls of the aem ems is there isn't a temp guage so i didn't know what the car was doing as of temp before this all started. The shop replaced the thermostat with a gates thermostat which i now know is not the same as a oem honda stat. (no bleader hole for air to get through) after getting the car back it would boil over up front from over heating again. after trying to blead the car for a week i gave up and returned the car so the shop could replace the thermostat under waranty. Again my car overheated, after a little research and pulling the stat out myself i noticed it didn't have a bleader hole in it. I replaced the stat with a honda one, and after a complicated bleading session i had the car back to normal temp. So with my computer in had i drove around for a week and the car would stay at 189 to 190 degrees.

Now at the end of the week my temp started steadaly increasing, so i then went to my friend who had the chemical to do a co2 test to see if my headgasket was leaking, this test turned out negative which really put a smile on my face but didn't solve my cooling problem. After hrs of searching online i redid my bleading proceadure and it didn't fix my problem. The next thing i turned to was my water pump and after removing that tonight it seems like it is in good working order. I am lost guys, am i simply not bleading it correctly? Do i need to do more tests to see if it is a head gasket? Any information would be greatly appreciated. Let me know if i can provide any more information, i really dont want to take the car to honda with the modifications i have done to it, i am worried i will end up with more problems.

 

I am having similar problems. I have replaced the thermostat, hoses, radiator cap, radiator and checked the water pump. I have done a lithium test and pressure checked my cooling system. I have also drilled my Intake Manifold Gasket.

After each invasive procedure I have bled the system as best I know how and the damn thing still overheats intermittently.

One thing I would recommend though is an AEM Serial Gauge. It plugs into the AEM and gives loads of information including the Engine Coolant Temperature.

 

Here's my thread on the issue:

https://www.s2ki.com/forums/index.php?showtopic=681309

 

https://www.s2ki.com/forums/index.ph...pic=666773&hl=

read this. we had the problem and mine was the worst. i fixed it. it is almost 100% you thermostat. go to honda and buy an OEM thermotat. if it does not have the bleeder hole in it it will not bleed all the air out of the system resulting in a small sir pocket. this air pocket at this point is very small resulting in no problems. shorty after running the car for a day or two the bubble will grow. what happens is that this bubble's air gets superheated. this means that the air inside it is hotter than the water around it and is actually causing the coolant to flash off into steam resulting in a little bigger air pocket. this continues to happen until now you have enough air in the system to show up and cause a problem. i have wasted about $500 trying to find this problem and almost had a new $1200 headgasket. dont make this same mistake. please if you have a question about bleeding the system shoot me a pm and ill will give you my method and the method the mechnic used in the end that has fixed my problem. this was about a 5 month search for me. i hope my fight to find it will help you save the headaches

 

Thanks for the fast feed back, i will take you up on that bleeding procedure. I just found the post that is right below mine which explains alot of the problems i am having. i am almost posotive it has to do with air pockets. I have a new thermostat and i am going to replace the radiator cap once more to see if this helps. I also might be screwing myself on my bleeding procedure i would like to know how you have done it. thanks again

 

well the way i did it was sit in the driveway and let the car heat up to running temp. turn the heat to full. pull the cap off the bleeder on the firewall and let it gurggle out. stop after a little bit and cap it back off and shut the car off. check the coolant level in the radiator and the overflow. top it off and repeat until you get on a steady stream out of the bleeder. make sure you top off the fluid after your done. this makes a bit of a mess, but it worked. the coolant is hot, but not too hot just be careful.

is this the way that honda tells you to do it? no....did it work? yes.... this is the way i did it as well as my mechanic. give it a shot i bet you will get it.