I replaced the thermostat a while back with and OEM one, and it still overheated. Now i thought it was the fan clutch goin, but i just changed that with a new one from mazdatrix and the temp. gauge still keeps goin up. maybe air in the system? i'll go drain and refil the coolant now, maybe that. but this is pissin me off. also, i'm not losin coolant (i don't think) but i'll check the radiator and/or hoses for any leaks. any other ideas are appreciated

thx scott

 

no need to drain to get the air bubbles out, theres a bleeder valve on the top left side of the radiator

look at base of the waterpump pulley and see if theres and water or coolant residue coming out the weephole, your water pump maybe going out.

also do you still have the plastic undertray installed ? that helps immensely sometimes

 

There is a good write up for troubleshooting your cooling issues here:

http://www.aaroncake.net/RX%2D7/cooling.htm

I had a similar issue with my car and it turned out to be that the gauge was wrong, I swapped the cluster from another 7 in and it went back to normal. Ticked me off b/c I replaced almost everything... hoses, waterpump, T-stat, radiator... then it turns out the car's not overheating at all.

 

thx. car is def. overheating. last time i drove it coolant burned a pencil tip sized hole through the overflow tank and coolant was shootin out like a geyser. i do have the undertray installed, and i have the sport model so i got the lil metal one too. forgot bout the bleeder valve so i'll do that, and i just got bought a new rad. cap at autozone. it opens at 13 lbs. but it's stant, so i dunno if it'll work.

again, thx for the info.

 

i replaced thermo once and forgot to bleed it, it overheated again, i bled it, no more overheating.
Whats the deal with those bleeder valves i jst take the radiator cap off and start the car??

 

i would replace the water pump and flush the rad

 

Get an OEM rad cap for sure. And yes, leave the rad cap off and loosen the bleeder screw and fill 'till no bubbles come out. Once this is done, you still want to run the engine with heater on hot, and fill as the engine warms up and bubbles escape.

If you really want to be cautious, you may want to fill the system with the thermostat and neck removed. I had air in the system just before the thermostat and it didn't want to open because there was just air around it. This is what I'll always do in the future....coolant change along with rad cap and thermostat. I'll actually be doing this very soon and hope to take pics or footage.