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Water Noise from heater core


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All -

 

I have a 90 2.2 legacy. I have been hearing the sound of water behind the dash, and figure its the heater core. Does this mean that there is a problem looming in the near future?

 

Thanks,

 

Rich

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Thanks for the data everyone. I was hoping it wasn't going to be a major problem, since everything seems to be anymore.

 

I will keep an eye on the temp to make sure it isn';t periodically getting hot, and will add some more coolant.

 

Rich

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Sorry to rain on your parade, but if the sound has appeared by itself, ie. not in conjunction with a coolant change, then you probably have an internal headgasket leak. Compression gas is seeping into the coolant through a tiny hole. Usually too small to be exposed in a compression test.

 

I suggest that you park the car with the front slightly higher than the rear. Let it cool right down, open the radiator cap and the bleeder screw (opposite side to the rad cap) and put the heater on full blast. (Just the temp, not the fan!) Brim the radiator with coolant.

Make sure the expansion bottle is filled between the FULL and LOW marks. Also, remove and flush the overflow hose to make sure it isn't blocked.

 

Start the engine and let it run at fast idle, don't touch the throttle. Once the revs are down to normal idle speed, a little throttle massaging may be used to heat up the engine a little faster.

 

Keep an eye on the coolant level, as the engine warms up it will expand and eventually start to overflow. Thats when you screw in the bleeder and shortly after the rad cap.

 

This will bleed most of the excess air out, the rest should find it's own way out via the overflow bottle.

 

Now, drive the car and keep a watchful eye on the temperature and coolant level. An HG leak like I described above will often cause overheating AFTER a long high speed run.

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I took my car on a 1600km trip just recently travelling at average 110kmh and it never even hinted at getting warm,hasnt got hot since owning it a year with the water noise.

Sounds just like water sloshing around under the dash,

Plus it hasnt used a drop of coolant in the last 8 months.

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Mine is making the same gurgling sound. I've noticed it recently.

 

I probably should try bleeding the system again. When I did my t-belt this past weekend I did notice the overflow resevoir was at the low mark....so I did fill it back up.

 

I'll bleed the system and see if it goes away. I suppose it's very possible for an internal headgasket leak. However I may have introduced air into the system when I did my injectors a while back.....and never completely got it out. I may try bleeding it tonight. I want to go for a drive tonight.

 

I haven't noticed anything out of the ordinary in terms of overheating or high temps......

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Originally posted by Setright

Someone on the board had success with bleeding the system by removing the throttle body coolant hose - but yours is bypassed right Josh? - since its the highest point in the cooling system

 

It might be my minor debacle that your referring to, except that I didn't actually bleed the system at that point, but rather I had air trapped there after having done the bypass mod incorrectly.

 

Instead of correctly reconnecting the two hose sections after removing them from the TB, I simply capped them off, causing air to be trapped in the hose-ends (instead of letting it pass through and out).

 

I still have a slow bubbling in the O' flow, but not as severe as when the TB hoses were capped off. Not sure what that's about but I've got my eye on it.

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I do not think that the head gaskets have any problems. I drive interstate and city constantly, and never have overheating or temperature issues. IT pretty much only happens when I first start the car and pull out on corners or hills.

 

but thanks for all the replys.

 

Rich

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Originally posted by Rich

I do not think that the head gaskets have any problems. I drive interstate and city constantly, and never have overheating or temperature issues. IT pretty much only happens when I first start the car and pull out on corners or hills.

 

but thanks for all the replys.

 

Rich

 

Sounds exactly like mine,hasnt had any troubles in the last year of owning it,so Im not really inclined to do anything about it.:)

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