You left your radiator cap off and its boiling over.

 

no i have my radiator cap on....It happens in bout 10-15 mins of drivin

 

hey, where did my post go?? oh well i'll write it again. I have an '88 13bt manual and its overheating quite alot. All the water seems to be goin into the radiator overflow, where it over flows out the overflows overflow.
I've checked for bubbles in the coolant when the engine is idling and i dont think there is any but, it jus happened then and i think there may have been very small bubbles but ill have to look again later cos they werent there last night and its done it quite a few times before but its getting VERY frequent now. I HOPE its not my seals...

 

Sorry, I was just being flip when I wrote the first time. Was not a lot to go on then. Tell you what, Fill up the radiator, and I know you'll be sure to bleed it with that bleed screw on the side of the radiator if you have it. Put only enough water in in the overflow tank to get it to full mark which is somewhere in the bottom quarter of the overflow tank. Go drive the car for a while, and when you stop, leaving the engine running, get out and open the hood to look at your overflow tank. If the car is spilling its guts into the overflow tank, well you might buy another radiator cap and maybe a thermostat and try again and see what happens. If it still overflows, well I'd say bad water seals. Another tack is to fill it up with water, run it a while. Park for the nite. Next morning get up and pull the bottom plugs prior to starting the car. Water, if leaking into the rotor housings, will collect and pour out when the plugs are removed. Welll maybe not pour out, but dribble out. If you see water, too bad. Rebuild. No radiator stop leak allowed whatsoever.

 

u might have a little puncture in the hose running from the top of the radiator to the over flow bottle. when the coolant gets hot, it will overflow into the bottle some, and then when it gets cold, it will suck some of it back into the radiator. if there is a little puncture, it could be keeping it from sucking the coolant back into the radiator. just something else for ya to check.

 

I had a leak that would set my buzzer off after about 10 miles of driving. Found out I had a hairline crack in my thermostat cover (it's plastic).

If you're not sure where this is, it's connected to the end of the upper radiator hose at the front engine cover. My crack was only visible with a small mirror (yeah, I know HaHa) - I removed the cover (replace your $14 thermostat while you're at it, as the spring wears out from heat with age) and I could see about a 2" crack so thin I couldn't even see a flashlight shining thru the inner wall. Doesn't take much.
I got both parts from Mazdatrix. Totally fixed.

Hope you find out what it is.

 

Yeah Thanks that seemed to be the problem the overflow hose had a small crack in it, When it heated up it pushed water into he overflow but when it cooled down it just sucked a big air bubble into there. I also replaced the radiator cap jus to be safe and im gonna get a thermostat soon too. thanks

 

if you overheated it, your water seals could be shot. The pressure from the combustion chamber could be forcing the coolent out of the rad into the overflow. If this is the case, you need a rebuild.

 

I could be that one of your hoses (IN or OUT) are loose and it could be burning as it leaks so u would never notice except the smell