overheating problems....sometimes

Ok, here's my situation. My b16 overheats on occasion. Once sitting in traffic, everytime i make a hard run, and AFTER extended drives at semi-high RPM's (like on the interstate). These are the steps have have taken so far....

New thermastat
Fushed out the cooling system
New Fluidyne Radiator and fan (yes, the fan is moving air the right way)Checked water pump (coolant flows fine with radiator cap off)
Ran compression test (within 3 psi across all 4 cylinders)

Now the car does give off some white smoke at times, mainly on start up. And my tunner said because of my Hondata unit, its gonna smoke a little. But it has me worried. There are no external leaks.
But the thing that has me puzzeled the most is, after i run the car hard, the temp climbs up to about 3/4 to 2/3 on the temp gauge. It boils out the coolant over into the resivor (and even out of the resivor), BUT IT DOESN'T FEED BACK INTO THE RADIATOR after it cools. Not even after overnight.
My fear is that I might have a cracked head.

Does anybody have any ideas before I start taking this thing apart?

did you replace the cap ?

u probloably have air in the system thats y its not going back into the radiator maybe idk u need to have a airless cooling system in order for it to work properly.

I replaced the cap before the new radiator went it. Plus the new radiator came with its on cap.

If i do have air in the system, where is it coming from? There are no visible external leaks. So I'm thinking if air is leaking in, fluid will be leaking out, right? And if its not coming from anywhere, how do I get the air out? There's no bleed off valve on a 2000 Si. I know you refill the system with the cap off and let it cycle through, then refill it again. But if there's something I'm doing wrong please let me know. Man, this is driving me crazy.

whenever your flush your cooling system theres going to be air in it. and it will overheat till all the air is out

at the top radiator hose where it comes off the block there is a bleeder valve.. bring the car to operation temp. and then remove the cap. open the bleeder valve and let all the air out. close the valve make sure you keep the radiator topped off so you don't get more air in the lines.. bleed it a few times to make sure it's all out..

head gasket?

I'm really hoping its just air in the system, but i dout it. I ran a compression test and all 4 cylinders were within 3 or 4 psi of each other. Doesn't seem to be any coolant in the oil, or the cylinders themselves. I'm not too sure what the signs are for a cracked head, but I assume there along the same lines as a blown hed gasket. So I'm kinda at a loss. I wondered about my ignition timing. I let my tunner set up the Hondata system cause he's a lot more familair with it than I am. I'm just wondering if its possible to have too much timing advancement to cause overheating, but still have no signs of detenation.

what are the comp #s like in order ? sounds like you got a leak some where if white smoke comes out. it would be internal also with no visible signs outside. if you keep overheating you will defintely
warp the head. if you do take head off check for
warpage. but still something is not working right to over heat. could be sticking parts and not actually faulty.

One thing thats got me a little puzzeled is that when i go to bleed the air out of the system (with the cap off), the coolant runs out the top of the radiator before the thermastat opens. And I don't mean a little. It gushes out. I cant remember the exact numbers across the cylinders. I didn't bother to write them down. They were like 162-165 psi. (that is with 8.5:1 compression pistons). And I don't no what parts could be sticking. They have all been changed out. But anyway, I'm all out of easy fixes. I'm just gonna have to take the thing apart and check it out. Plus it gives me an excuse to have the head (or probably a new one) worked. :biggrin:

you need to make sure the car is at operation temp before taking the cap off so it wont make such a mess all over the radiator....

sounds like you got a combustion leak. water should not gush out like that. if anything it should go down with water pump flowing. try taking a pressure tester if you have one and test for leak. (follow instructions to attach tester head to radiator neck, and start vehicle and watch it build up. if it spikes immediately shut off. BLOWN HEAD GASKET. if slowly rises, leaking. good luck

Thanks for the advice. I'll find a tester somewhere and give it a shot.

I had a b18b motor in a DA once and it was over heating sometime just like you mentioned. It also smoke alittle too, I found out that it was a leak in one of those SMALL coolant hose located around the intake manifold. There are about 3-4 of those little ones and 2 large one of course. So you should check your hose from my experience, I had to buy a new motor because I drove it continuosly and ignored it. So yeh, the hoses should be replaced every 5 years, it cost around 15$-20$

i recently had a cooling problem too. a few of my smaller hoses had cracks in them and were leaking coolant. i drove the car until it would start overheating then pop the hood and look for the leak. luckily i found the hoses and replaced them. i also added some radiator stop leak solution and some coolant cooler, supposed to lower the temp by 20-40 degrees. it does help ecspecially in the summer when its 90 plus. good luck with your heating problem.