Hi everyone,

 

I'm hoping someone here could help me out.

 

I have a '94 model Legacy that has air bubbles stuck in what I'm assuming is the heater coil. Periodically I can hear the sound of bubbles gurgling through something in centre of the dashboard towards the firewall.

The noise isn't there all the time but when it is it drives me crazy.

Last night a leaking water pump and the timing belt were replaced (not to try and fix this problem, it was just maintenance) but it failed to make any difference to the gurgling.

I have previously replaced the coolant and tried to bleed the system to fix the gurgling but that didnt work either. There are no apparent leaks anywhere that I can see, coolant or anything else, and the car is running fine otherwise.

 

Any suggestions?

 

Regards,

martin

Um are u running the a/c?

Um are u running the a/c?

 

the noise happens when the a/c is on and off, thats how i decided it was bubbles in the coolant.

also, if i jump on the accelerator to make it change up i can hear the bubbles rushing through faster as the engine revs get higher.

Hm....would a head gasket issue cause this problem? i.e. blowing exhaust into the coolant?

i guess a faulty head gasket could cause the bubbles but the car is running smoothly, the coolant looks fine ie. there's nothing in it that shouldn't be, the thermostat is working correctly, engine oil is in good condition.

 

the only other cause i could think of would be if the heater coil itself had a little hole in it but i ruled that out as there is no smell or signs of coolant inside the car.

So its really loud from the inside, might be something else ur hearing. Like a vent switching but struggling. But i wonder if it could be air bubbles in the radiator.

Any loss of coolant in the radiator? If so, leaking head gasket may be the issue. Let me know what you find out.

Top off the coolant & bleed the system

 

You need to remove the bleeder screw to bleed the air out of the system

 

Here is a picture of the bleeder screw, looking down just past where the radiator hose comes into the radiator

http://www.main.experiencetherave.com:8080/subaru/images/edmproject/DCP_3934.JPG

 

Here's another one that shows it in relationship to everything else

http://www.main.experiencetherave.com:8080/subaru/images/timingbelt/DCP_2731.JPG

Any loss of coolant in the radiator? If so, leaking head gasket may be the issue. Let me know what you find out.

 

coolant level in the radiator and the reservoir is normal and still no leaks found anywhere.

Top off the coolant & bleed the system

 

You need to remove the bleeder screw to bleed the air out of the system

 

Here is a picture of the bleeder screw, looking down just past where the radiator hose comes into the radiator

http://www.main.experiencetherave.com:8080/subaru/images/edmproject/DCP_3934.JPG

 

Here's another one that shows it in relationship to everything else

http://www.main.experiencetherave.com:8080/subaru/images/timingbelt/DCP_2731.JPG

 

thanks Legacy777, i'll give it another go... might not have much time this week but i'll post my results when i do get it done.

on a side note, can i just say thanks to everyone here for your suggestions.

i wasn't expecting to get so many responses as quickly as i did. this is a really neat resource for subaru owners

This is just a thought. The A/C has a drain that can clog and can fill up with water. It is more of a sloshing sound than a bubbling sound. Water under the mats is a symptom.

The Subaru is a PITA to get the air out of the cooling system. The local shop told me to run the engine with the Radiator cap off, resivor full to the line and keep topping off the filler neck. Squeeze the bottom and top hoses every now and again it can take 30 min+ to complete the process and repeat. Run a search here on cooling system for more specific instructions

Also the doors can hold water if there drain holes are plugged, again more of a sloshing sound.

well, i fiiiiinally got around to looking at this today.

i tried a method for changing the coolant suggested in another thread. it has improved but i can still hear bubbles, they're just a lot quieter, so im assuming there's fewer of them this time.

i'm going to keep an eye on how things go over the next few days and try bleeding the system again.

 

thanks for all your help. this place really is useful. i've learnt a lot

 

marty.

I have two of the 2.2 engines in Subaru's. One looks almost like

the one you use pics of....except for one thing. Whats the red things

in back next to the firewall. I hope its not something I should have

on my Subaru's...because it's gone if it belongs there.

 

Richard