strange noise

[bigtow]

hi all i have just driven home from work(nights) aprox 25 miles when i switched the car off i heard a strange gurgling noise i think from under the dash it is not the first time i have heard it. it is quite a deep gurgle/rumbling noise it is not constaint aprox 5-10 seconds in between. i did chainge the coolent a few months ago but i have only just noticed this noise any clues?

[97LT1Z28]

Re: Strange Noise

When you changed the coolant, did you follow the bleeding procedures to get the air out of the coolant system? Also, have you changed the thermostat?

[bigtow]

yes i did chainge the stat for a 160 one and as far as i know i did bleed the system. but if any one can post the corect way it would be helpfull as i folowed the haynes manul but not to sure if this is corect

[97LT1Z28]

Re: Strange Noise

I don't know the exact procedure but this is the one I follow: With engine completely cool, start it up and let it idle. Use a standard screwdriver to loosen the two small brass bleeder valves - one is on the neck that houses the thermostat, the other is on the top heater hose coming off the water pump. As the engine heats up, coolant will start to seep out. When both start to seep, close them and you're done. If this doesn't correct the noise, then your coolant may be boiling-over - perhaps a thermostat problem?

[94 formula]

I agree with 97LT1Z28 on the coolant system bleeding procedure. Also when you fill up your coolant if you keep filling it to the very top a decent amount will go into the overflow tank and overfill it. My car did the same thing you are describing when I got to much in the overflow tank.

[bigtow]

hmmm about a month a go the low coolent light came on i can not find any leaks so i checked the levle in the rad and that was full so i toped the over flow tank up to aprox half way altho it is quite hard to judge on thoes stupid dip sticks i think i put in about a pint. that is the way i did bleed the system. when i got home tonight in did not do it ?