yea yea i searched but want a more specific answer.

Cars temp guage has been going rather high lately, popped the hood today at work and coolant was leaking onto the ground. Looks to be coming out of the top of the overflow tank and the tank was shaking from pressure i assume, even after the car was off. I know the coolant needs flushed but I have a hard time believing thats the root of the problem. b16 does smoke when vtec kicks in and have caught it shooting flames at the track

head gasket?

im hoping for the radiator cap but i know thats not it

 

Well I guess do the obvious.

Drain radiator and fill up with good coolant.
Remove old thermostat and replace with a new one.
Bleed the cooling system.
Check if fan comes on.

Work from there. If problem still comes up, check water pump.

 

Overpressurization of the overflow tank is a sign of a blown head gasket.

Certainly try the things listed above, but IMO you're probably dealing with a blown head gasket.

The easiest way to check for a blown head gasket is to get one of those funnels that screws on top of your radiator like a radiator cap does and has an overflow portion on it. You fill the funnel up and actually leave more coolant in the top and have the car running. After the car reaches operating temp and the fans cycle (if they ever do) then a car with a blown head gasket will continue to burp bubbles up through the funnel. A normal engine will not burp any more bubbles after the fans cycle.

The funnel alao has a stick with a rubber o-ring on it that you insert to prevent spillage upon removal of the overflow funnel.

Another check is to have one of those cool dye testers. You get a reading of the gasses coming through the radiator where the cap is supposed to be, and if the blue dye senses any exhaust gases it turns green.

These are the two ways my shop checks for blown head gaskets when they are not 100% obvious, and sometimes we can catch the slightest of cases and save the customer an engine replacement.

Ask around your local shops to see if they have either way of checking your head gasket.

 

Thanks Tom, I was hoping you would respond. Luckily I have the day off work tomorrow too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 &raquo;</TD></TR><TR><TD CLASS="quote">Overpressurization of the overflow tank is a sign of a blown head gasket.</TD></TR></TABLE>

 

i'm with Tom that your problem could very well be head gasket related...however,a few years ago,my rad cap spring was so worn that it wouldn't hold hardly any pressure.when the car would warm up,coolant would push right past it,into the overflow.if you kept driving the car,it would do until the overflow had boiling coolant spewing out.
anyways,you might want to try a $5 rad cap before spending any more money-it could just be your problem.
Chris

 

jus went and bought a new radiator cap from a local shop for $4

now im jus waiting on the engine to cool down so coolant doesnt spray all over... i have a bad feeling that this isnt the reason though.

 

ok so i have bought two radiator caps so far and neither fit correctly. I got one for a sohc radiator(stock from my car) and one from a b16 dohc and the dohc is wide enough but will not turn to 'latch' properly like the piece STR cap that i currently have...any idea?

 

fan is not coming on at all it seems. I popped the hood after a 20min drive and temp guage was hot and no fan.

 

so anyone have any more ideas? today the i drove the hatch to work today and the temp guage was hot, but no coolant leak. Im going to rent a car today after work so I can take her in to get tested. blah

 

im sorry but the pistons really suck!

 

dont clutter up my post w/ your noob mindless bullshit.

 

this is what caused my D15 to blow... the fan switch went bad and the fans didn't turn on while driving on the highway.

 

an overflow at the tank means that the motor is running hard therefore making your pump run hard too. which means your system isnt necesserily getting hot, but its not flowiing wright. you can do two things, hook a toggle switch to your fan, just tap it in the positive wire so just in case you forget to turn it on, it still kicks on. but if you start running your car hard, turn on the fan. and the other is to drill holes in your thermostat. what is what i did and my car runs a lot better, not necesserily too cool but just right.

 

The same exact thing happened to me in my A4. I checked the thermostat, and headgasket but it was the water pump. Try one of those there only a hundred bucks and its always a good thing to replace before it goes out and breaks something else.

 

so it turns out its the coolant temp switch....