This is my 3rd one thats had the bottom section of the cap get sucked off in about 4-5 months...

1. Ive changed the thermostat already
2. I have no leaks
3. Ive bled system properly an have no bubbles
4. Compression was fine on all 4 cylinders

The radiator will spew coolant out from the cap "even before the cap took a ****" and the overflow would randomly start boiling outta nowhere while just cruisin.. Also, the caps they sell at autozone dont fit to good either, i have to smack it pretty hard or push down hard on the cap while turning it to close it because its so snug on there... Anywho, could this b a bad radiator...? Doesnt seem like many people have an answer to this from my searching...

Thanks in advance...

 

what pressure cap are you using?

also, what water temps are you hitting?

 

sounds like a bad head or head gasket I realize your compressions is good I would try a leakdown test, I had the same issue on my d16z6 i changed the head gasket and had the head decked and my problem was solved. Im guessing your super heating your coolant with a small leak from one of your cylinders. Does the car warm up really fast?

 

Make sure a peice f the old rad cap rubber is not stuck to the neck of the rad had this happen before capt the cap from sealing right. But if thats not the case I to would look at the hg being the problem go have the coolant tested for exhaust gasses in it. Its an easy cheep test you just need to find someon that does it

 

buy a cap from honda orr even better get like a spoon one that is made for higher temps...

 

thanx for the quick feedback guys... once i get off work ill try those tests... also, stoppin by honda on the way home for a new cap.. hope they come with warrantys lol..

 

also, if it were my HG wouldnt coolant/oil be mixed..?? because my oil is fine... i just got back from the stealership where i got my 25$ radiator cap so we'll test that as soon as im done work...

 

Hondas tend not to mix the coolant and oil due to the design of the block. I have worked on many blown hg on honda and not one of them had mixing of the oil and coolant. Thats not to say it can't happen I am sure if you run on a blown hg long enough it will fail in that way.

 

So what step would u take first if u were me..?? Leakdown Test, System Pressure Test, Exhaust Gas in Coolant test..???

I was just reading someone with similiar symptoms as me and they said it was their IM gasket...???

 

its hard to tell just by looking at the oil. check the color of your coolant...my coolant was still green but had black swirls in it, the oil looked normal...

 

well since i flushed my coolant 2 weeks ago i've just been using straight water, but that turns brownish in a matter of days... i figured that was normal since its burning up so fast tho, and my cars not smoking at all... but i do smell coolant inside the car while im driving tho...

 

water doesnt burn

 

Why don't you use the pre-mixed antifreeze? It's pretty cheap for a large container...

 

your dumb.... you know what he meant.

If there is air in your coolant, your headgasket is mostly likely damaged.

 

ya kno, my car does heat up rather quick now that u mention it.... thanks for pointer...

 

i do use premix, but since my cars been doin this **** "couple weeks" i've only used water so im not spending 10 bucks every couple days... once issues solved i'll 100% go back to antifreeze..

 

after i top off my radiator and let it chill a couple minutes, the bubbles seize.... leadin me other ways from my HG but than i hear everyone sayin its HG lol so im re-convinced...

 

so last night i finally did the coolant bleeding steps and after about 35-45 minutes i'd still have a bubble or 2 come up to the top of the radiator... so after that for about another 10 minutes i closed the cap, an cracked the bleeder open an it starts bubbling everywhere for about 15-20 minutes, well than it'd almost like foam/bubble around the top of the bleeder valve an than stream coolant for a minute or two, than it'd foam/bubble again, ect ect... but my compression was perfect so im stumped...

 

maybe your radiator is jacked up where the cap sits.

 

Yeah, i'll second that, maybe you need a new radiator?? Second, you can get a pump or have a shop do it. It will pressurize your coolant system and you'll be able to find leaks easier that way and you can look down into the cylinders and see if there is coolant in them.

 

i thought maybe it was my radiator and also maybe it was the radiators of all the other fellow HT guys who had this problem and replaced "head gasket, water pump, ect" and still had the issue... anyone have any luck with the ebay dual core ones..?? I'm going big boost so i'd like to upgrade a bit..

 

so after 2-3 hours of driving my car felt fine, than i pulled into KFC and heard a loud whistling..?? so i pop my hood and there was steam and coolant spraying out real crazy from under the resevoir cap and was shooting everywhere!

i let the car chill for 45 minutes, i filled it up with about a gallon of water than it was topped off.. drove it 20 minutes home & it was fine the whole way & when i got home.. WTF..!!! i might just take my **** to my uncle on this one "certified 35+ years auto/airplane mechanic" and see if he can help me with this one... i dont feel like one by one by one replacing every single little suspected bad item for it not to be the right one... im just suprised theres not 100% answer on this one yet lol..

 

X2

There are very few instances where there is a problem and there is only one cause. If your getting air into your coolant, it can only come from one place, a leak. Honestly man, if your radiators fine, and you don't have any external leaks, than its internal. Ether your block is cracked, head or block surface is warped, or your head gasket is failing.

 

...i would do what he said...CK!!!

 

Sounds like it's your radiator from this