My Disco II '04 has been giving me the waterfall sound on acceleration for a little while now. Hasn't overheated or anything, but unless I'm mistaken, that almost assuredly means there is air in the heater core. Am I right on that?

I had replaced a couple coolant hoses a few months back that had snapped, and flushed the system to put new coolant in it, then bled the system, or so I thought.

Just tried bleeding it again today, using the method outlined by Disco Mike here: landroversforums.com/forum/discovery-II-18/why-I-cant-bleed-coolant-system-d1-29596

The heater is working greater and is really hot, but I'm still getting the gushing sound when I accelerate.

Do I just need to bleed it several more times?

Thanks,
Matt

 

I've changed coolant several times and it normally takes me 2-3 times of the proper bleed procedure before that sound goes away.

I've read from other owners that they are never able to get rid of that sound, but don't have any issues associated with it (except the annoying sound).

If you didn't have the sound before and now you do, it's probably just air and you have to bleed it a couple times

One other thing to consider... when you let your system cool down and screw off the expansion tank cap, does it still contain some pressure behind it? I've noticed on my truck when that happened I actually had a HG issues and the cooling system was over-pressurizing.

 

I had my system open a couple times over the summer and after I do the initial bleed technique that you always hear about, I will slightly open the bleed screw on the T-fitting while the vehicle is running and getting up to operating temperature. I will crack it open just enough so that the air can fizz out for about 1 minute. Then, I tighten it back up, turn the heater on inside the cabin and repeat the process of loosening the screw and letting air and fizz escape, close it back tight for a few minutes. I repeat the process several times while keeping tabs on coolant temp. You should be checking the temp with a secondary device. Pay no attention to the factory temp gauge on the instrument cluster, if you didn't already know. I have never had the waterfall or gurgling noises when using this procedure. Anytime you loosen the bleed screw with the motor running, you must hold it in place until you tighten it back, or it can easily unthread itself and shoot off somewhere.

 

Chubbs technique is pretty interesting. I'd give it a try.

Also you can check out this thread, which almost eliminated the gurgle in my truck.

https://landroverforums.com/forum/di...chnique-48558/

 

An alternate technique that gets favorable results consistently is as follows:

With engine COLD, stone cold, and not running raise the overflow tank as high as the fragile hoses will allow. While the tank is elevated open the bleed screw and let coolant flow out until a clear stream is achieved. Note to not let the tank go empty during this procedure... Top tank off as needed to get to a clear stream.

Once the stream is clear shut bleeder screw and replace tank to its location and top up/cap.

Now run the engine... If you still have waterfall sound repeat process.

If waterfall does not go away still, you have a leak letting air in somewhere.

 

Time slipped away, but I wanted to jump back on here to say, thanks for the tips guys! I ended up finding freedom from the gurgle thanks to you, Dave03S, thanks a million! Makes me a happy LR owner.

 

Try bleeding it with the front of the car elevated on a hill or jack stands. I just switched to waterless coolant which meant that I had to do this twice, and it worked both times, and I never got the waterfall. Could be dumb luck, which I don't have much of, but I did make a point of the last time I did it that when it was up on jack stands for brake work to bleed it again.

Be patient and good luck.

 

Actually the best "alternate" version of this has been posted by Number9 in other threads.

No hills or jackstands required, no removing the overflow tank... no mess of coolant going everywhere while waiting for a steady stream.

Just open the bleed screw while stone cold and using a small funnel add coolant into the bleed hole in the T connection until it will take no more. May take doing this two or three mornings in a row but you should be adding less each time.

Again props to Number9

 

I've tried everything to bleed the air out the cooling systems. I've done it with a hot engine, cold engine, truck parked on steep incline up hill, raised up the coolant bottle, climate control heat on max and still have the gurgling/waterfall noise when I turn corners.
I even drained the 2 condensate drains under the truck to see if water was in there making the water sloshing noise. They were dry.
I seriously think this could be trapped water inside the firewall area from my cracked windscreen cowl.

 

The noise is usually is coming from the heater core. Are you overheating? If not, driving it around should be ok and top the coolant when the engine is completely cold. I assume that your system is not leaking, it might take some few tries doing this but often works fine in my case. I don't have the valve on the Tee.