Waterfall sound behind dash...

johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
hmmm...this kinda scares me...I just realized that when the car is cold, sometimes it won't make the waterfall sound...it sounds totally smooth and quiet like it should... I'm not sure what this means...

Maybe when the car cools, the bubbles move to other parts of the cooling system...then when it heats up again, they all re-collect in the heater core as pressure rises?

Or, are all of the air bubbles purged out of the system when the car is cooling down, and then exhaust bubbles from the combustion chamber enter the cooling system while the car is running, and then they collect in the heater core...?

Jeez...I wish I knew.
 
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C

CFSapper

AKA Slient_sniper
Apr 24, 2006
796
0
0
Chilliwack
at first i didnt really pay to much attention to it thought it might be the oil or something and didnt worrie bout to to much
until i read your thread
 
suprabee

suprabee

Celicasupra.com Member
May 18, 2006
117
3
18
Scotts Valley, California
johnathan1 said:
hmmm...this kinda scares me...I just realized that when the car is cold, sometimes it won't make the waterfall sound...it sounds totally smooth and quiet like it should... I'm not sure what this means...
.
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When the engine is cold the heater valve (which allows coolant to flow into the heater core) remains closed. No coolant enters the heater core and this is why you don't hear any waterfall sound. This happens so the engine can come up to operating temperature as quickly as possible without losing heat via the heater core. Once the car warms up a bit, the heater control valve opens via a vaccum control and allows the warm/hot coolant to flow into the heater core. This heater control valve is also controlled by the setting of the temperature on the dash control, so that in the lowest setting, the valve is closed and no hot coolant flows to the heater core, thus you have cool air entering the passenger compartment. Increase the temperature on the dash control and it opens the heater control valve and likewise you now have heat entering the passenger compartment.

So you should only hear the waterfall sound when (1) engine is warm and (2) you have the temp setting above the lowest mark of 65 degrees. If you do hear a waterfall sound, then you have a malfunctioning heat control valve and it could be (1) the valve is defective and never closes completely or is stuck in an open position and/or (2) there is always a vaccum applied to the valve keeping it open at all times. This should be easy to determine if, when the engine is at normal operating temperature, you should have NO hot air coming out the vents when the heater setting is at it's lowest. If you do, then the valve is stuck open either fully or partially......oh and I thought I would add that all this means is that you will always have heat and it will just take your engine longer to warm up to operating temp.


rick
 
johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
Yea, i know about the heater control valve...although I didn't realize that it was closed via vacuum while the car is warming up...

I still hear the waterfall when the dash control setting is at 65 degrees... Also, my heater has never worked...when I turn the control all the way to 85, the air coming out will be hot for about 5 secs, then it will instantly become room temp. air... any ideas?
 
T

turbo06

Guest
Thats funny I had a small little water fall sound yesturday and today I went for a cruise and when I got back I just took the cap off let the water fly out then refill it with the little tank in front (can't remeber what its called for some reason) and havn't herd it all day now.
 
3p141592654

3p141592654

90T
Oct 11, 2005
3,816
16
38
Thousand Oaks, CA
When I had the waterfall noise it was very intermittent. Most commonly it happened after idling at a light for a few minutes, and then pulling away. My coolant consumption was very light for many years, I would top up the reservoir every few months at most. My vote is for the beginnings of a BHG. In this case, I would start with a sniffer test from the radiator neck.
 
ChadMKIII

ChadMKIII

Yup, Thats The G/F
Jul 14, 2006
369
0
0
34
Bay Area, Ca
johnathan1 said:
YAY!!! Someone else feels my pain!! That damn sound gets pretty annoying, doesn't it?? It makes me not want to push the gas...I feel like I'm hurting the car or something...and I even dread driving it.
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I have the same symptom, but backwards.

Thats funny though, cuz I've only heard the noise when the engine was cold. Sounds like a waterfall somewhere in the engine, a little to the right. Only after the car has been sitting all night, and only on the colder nights. I've only had the car for a couple months, so I've never even used the heater, and the temp has been set at 65 the whole time. Its opposite of everything being said here lol. And it only did it at idle, after I brought it above about 2000 it stopped, and wouldn't come back at all. It has only done it a few time, very intermittently.

I wish I could help you but I haven't looked into it much yet, when I get time I'm going to ask a local mechanic who I know that owns a 90 Supra if he has any ideas. (hopefully tomorrow). BUt maybe me having reverse conditions can help someone to see if there are any other possibilities if the heater valve thing isn't working for you, jonathan.

My uncle (previous owner since 96) and my grandfather thought it might just be oil dripping thru the turbo, but it didn't sound like it really made since to me.

Having this car has taught me Toyota quality ain't everything its cracked up to be. ;)
 
johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
Yes, I am starting to think BHG too... I just have that "gut" feeling, lol...It just sucks because it was replaced less than 6 months ago...I put basically everything I had into fixing it, family drama and all... Then what does it do for me...totally stabs me in the back... I even used ARP hardware, and an OEM gasket, Permatex spray, resurfaced head...what did I do wrong?

I have also replaced almost every part of the cooling system...lower rad hose, fan clutch, water pump, those little 90 degree hoses...

Would it be possible to prolong it's life with a retorque? I am going to replace the valve cover gaskets tomorrow probably...would be the perfect time to do a retorque...what do you guys think? Could it still be saved?

I retorqued the hg on my NA, it was burning coolant, a little every week or so...I torqued them to 75ft/lbs on stock everything, and had the waterfall about 3 months later...damn Supras.
 
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johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
ChadMKIII said:
Having this car has taught me Toyota quality ain't everything its cracked up to be. ;)
Click to expand...

Lol, oil dripping...

I don't think it really has anything to do with Toyota's quality of products...I think that it is more of an age/owner/cheap aftermarket parts on a very precision car kinda thing...It seems like this car likes everything to be in perfect balance, and if everything isn't PERFECT...al hell breaks loose.
 
3p141592654

3p141592654

90T
Oct 11, 2005
3,816
16
38
Thousand Oaks, CA
Based only on my own experience, the block deck had significant damage that was only repaired by resurfacing. The fire rings left marks in the block that were a couple of mil deep. Obviously I haven't seen yours, but my guess is your block deck needs to be resurfaced to get a lasting repair.
 
johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
I was told by the previous owner that he had the block rebuilt...when I did my hg, I saw that it in fact had been, the cylinder walls were clean, no ring at the top either...you could still see the crosshatch pattern too. As for the block surface, it was very smooth...almost looked like it had been machined, it looked WAY better than any block surfaces I had seen at Aaron's. I can't imagine that being the problem...
 
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