HELP Cooling System Problems

drftking · Post by **drftking** » February 13th, 2005, 9:50 pm

Is ther any way to tell where the system is leaking from without a pressure test. Or if not how can I do a pressure Test at home. Car started to overheat when sitting at a friends house and but runs fine when im driving. Also I cant get any hot air to come out of the vents when the car is standing still, air is flowing but cold air. When I start to drive the air heats up. But then when I stop at a light the air turns cold again. This happens for the fist 30 min im driving in the morning. I know it seems like alot of Problems bit if anyone can help it would be greatly appreciated
THX

jschrauwen · Post by **jschrauwen** » February 13th, 2005, 11:03 pm

Possible air locks. But that doesn't address the possible leak issue. Sheet of cardboard under the car after it's been warmed up fully is what I would use...at least to try and find the general vicinity of the leak. This leak could translate into possible air locks in cooling system which could generate the spells of cold air from the heater. This may further progress into idle irregularities where the coolant temp sensor comes into contact with an air pocket. If it's a high mileage vehicle I may want to check around the waterpump area for leaks. I'm assuming your reservoir is at the correct level. When the car is cold remove the rad cap and fill if it is low. Leave cap off and start the car and let warm up. As the car warms up the thermostat will open and you should see the coolant level go down in the rad - top up. Rev the engine up to about 2k and watch coolant level drop in rad. Top up while revs are high and quickly replace rad cap before letting off on the revs - or coolant will spill back out.
Hope this helps.

SimonPK · Post by **SimonPK** » February 14th, 2005, 12:01 am

mine just did a similiar sort of thing - got hot & actually burst 2 hoses - I fixed the hoses & then the heater stopped wroking - turned out the thermostat was jammed shut with a piece of rubber seal that perished from the spring in the middle - it then freed up & stuck open which meant that the engine took forever to warm up & the heater too.

maybe yours is the same - not a big job to do - took me around an hour & cost $32 for teh genuine mazda stat.

drftking · Post by **drftking** » February 14th, 2005, 4:17 am

Thanks for the help sounds like a thermostat problem im going to get the cooling system serviced this week so ill have them chage it out then.
THC