Ok lately Ive been leaking coolant everytime i turn on the car. Well sometimes I would say. I check the hoses and nothing at all. so today I drove her and shut her oof and came back out a few minutes later and opened the hood cause I notice a littel puddle underneath the car. Again no hoses had water or anything wet looking on them I did however hear a noice like air coming from somewhere. I looked at the top of the radiator and noticed there was coolent. so I looked at the radiator cap and noticed the noice was coming from it. the little nipple that is there where you can hook a hose to it was leaking from it. well the noice was anyways. I put my finger of ther hole and it stopped. Could it be that my radiator cap needs replaced or is it doing what it soppose to? I just thoought that was weird and thought if air was coming out than it fluid was probably being pushed out too causing to run down the radiator and then slowly hitting the ground. that would answer why I cant find a leak.

so do you think its doing whats it soppose to by releaving pressure? or is it not soppose to leak like that? buzzer didnt come on today. temp stayed at ussual spot.

87 N/A automatic.

 

What was is the "normal spot" for you? It should be around 1/4-1/3 way up the gauge. I'd say replace the radiator cap with another 13psi one, and see if that did it. Was coolant leaking out from where the hose goes onto the nipple, or is there even a hose connected to it?

 

no hose connected to is that s why I could tell it was coming from there and hear the noice coming from there. as long as i have had this car, it has not had a hose ther. I bought the car from a mazda mechanic . It also has a rebuilt engine it. serviced and all by him. The temp has always been at half way. Thermostat has been replaced twice just to make sure it wasnt sticking here in last year. radiator was also flushed. never goes above half way mark though. and doesn have white smoke when starting. well perhaps for just about 2 seconds when it does the hole cold start by reving up high.

 

If I understand correctly, there should be a hose going from that nipple to the coolant overflow bottle.

 

check the low coolant sensor, on my 90 it is loose (vibration?)

 

well if its the coolant sensor that wouldnt explain the coolant leaking. I can see small puddles under the car every other day.

as for the nipple, the hose going to the resevoir tank, that hose is coming from the filler neck. to the resevour tank. The cap on the radiator has a nipple too and I posted on here before, and was told it is soppose to have on. Is that wrong?


basically there are two , I have on on the filler neck with a hose attached to it that goes to the overflow tank/reseviour tank. Then there is the radiator cap that has a nipple too with no hose attached to it. and thats where the air is coming out of. Coolant as well as teh car is cooling off or perhaps evern while im driving.

 

My 87 had 3 radiator caps, one above the thermostat, one on the radiator and used to have one between the overflow of the radiator and the overflow bottle.

Radiator caps fail frequently. Make sure the weep hole on the water pump ain't the leak.

You can remove the one between the radiator and the overflow bottle, it just adds another failure point and is worthless.

 

yea mine only has two.

one on the metal part where the thermostat sits in and the other on is on the radiator.

 

three radiator caps is kindof alot even though there are ones that have two.

 

oK now i have another question. which cat should be the one with the pressure spring? the one with the radiator ? or the one right above the thermostat? I bought a new on but want to make sure I put it in the right place. or are both pressure springs? the on i got is 13psi one. also , do i need to replace the one that has the hose going to the coolant overflow tank? I guess that is where the pressure spring one shoud be right? or working correctly.

 

Yep one above the Thermostat is just a fill point = highest. I don't think it matters if it has a spring or not. The one on the radiator is the one tha goes to the overflow bottle and is where the new one goes.