Hi all, this forum rocks, new to rovers. Need some advice on my heater matrix waterfall.

2000 Discovery 2 177k. Had it for a month.

Overheated once on the PO. Got it for cheap. I enjoy a challenge. Did some work on the cooling system. Been driving it around trying to figure out whats going on.

New expansion tank cap
New radiator (PO)
Bypassed throttle plate, leaked on pressure test
New 180 thermostat (PO had the stock)
Replaced old leaking ballooning hoses

Not overheating anymore UG 194-203 max
No coolant loss
Coolant tests negative for exhaust gases.
No coolant in oil or oil in coolant.
Pressure test to 22psi with no visible leaks.
System pressurizes fine top hoses are firm but not rock hard.
No engine codes except 3 amigos
Compression test at 145-150 for all cylinders except #7 was at 90.

I have tried the numerous bleeding techniques on this forum and cant get rid of this dang waterfall. Does it just take time?

How the heck is air getting in there under pressure? #7 slipped liner?

 

Don't go chasin' waterfalls
Please stick to the Rovers and the lakes that you're used to
I know that you're gonna have it your way or nothin' at all
But I think you're movin' too fast

 

Exactly! words of wisdom, listen to your Mom and buy a Subaru.

 

Now that I'm home, on a more serious note, I've heard of this bleeding issue before. As a matter of fact I had this very issue just yesterday. No, day before yesterday, my mistake. Anyway, it ended up being that I didn't have a hose tightened well enough. For me it was the one between the radiator and the thermostat.

If that doesn't work then get it running, raise the T-coupling up high once the hoses start getting a little warm, loosen the bleeder valve. It will leak either air or coolant. If it leaks air then you're golden. Let it leak the air out, probably not much, and then close it back. If it never makes it to the leaking coolant stage then shut the engine off and pour coolant directly into the bleed valve until there's no air.

 

For some of us, the waterfall is just a sign that we still have some coolant in the system.

Seriously, the waterfall is a common problem after opening up the coolant system, and some of us can't seem to beat it. You might try this:

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

I tried it (though for a shorter period of time), and it worked pretty well.

 

You can do similar bleeding procedure when cold. Each morning for several days while stone cold I removed bleed screw and topped off via the bleed fitting using a small funnel. First morning may have added 8 oz and amount decreased each day until air fully displaced by coolant. A few minutes per day, didn't need to keep removing reservoir, wasting coolant flowing out of bleed and making a mess. Might work for you too.

......

 

Thanks for the advice guys, I will continue to bleed the system cold for a few days and see if that helps. Do you think those compression test numbers are a bad sign? Maybe best case a stuck valve? Was planning on doing the head gaskets anways...

 

#7 could just be a valve issue. If you can get the coolant/bleeding issues taken care of you might be able to fix compression issue by freeing up a valve without pulling the heads.


Have you driven and bled enough to the get air out from doing all your coolant system maintenance?

......

 

Thanks everyone for the suggestions. Here is my update, this has been my daily routine:
On my evening commute I get the system up to temp then park with the passenger tire on a truck ramp to elevate the heater core. Before I turn it off I give it a few high rpm revs to get the air moving around then I turn it off and let it sit until morning. With the engine stone cold in the morning I pop out the expansion tank and stick it on top of the battery box with the help of a screwdriver, lid off. I then bleed off the air from the T and seal it back up. Then I drive to work and repeat the process. I did this all last week and the amount of air I got out of the system decreased everyday. Also the waterfall sound decreased. Now it sounds more like a light wind blowing through the trees. Think I might of got it, what a pain.

Tip: I pulled a brass bleed valve off of a spare Saab engine I have sitting around. It fit perfectly in the T fitting, M10 fine thread I think. Really cleaned up the bleeding process. I attached a small clear hose to it so I don't spill coolant everywhere and I can see the air bubbles as they come out.

 

Update and a new puzzle. With the waterfall sound reduced to a trickling stream and no incident over the past few weeks I decided to risk a longer trip this weekend. Seattle to Yakima to see the in-laws. About 300 miles round trip with a mountain pass. a good test for the cooling system. Temps over the pass were steady at 197-203. Pit stop half way I checked under the hood and the overflow tube on the expansion tank had puked out about a pint of coolant. (I zip tied a bottle by the expansion tank and stuck the overflow tube in it to monitor any loss) I didn't think to much of it at the time knowing that the system will empty itself to a happy level. I emptied the bottle into my spare coolant jug and continued on. We arrived in Yakima and the waterfall was back the expansion tank was empty and the overflow bottle was full. Crap. I decided to drink some beer and think. After some thinking and drinking the truck was cooled down enough and I decided to swap out the new expansion tank cap with the old one I had in my spare parts kit. I went to unscrew it and the top came off in my hand! Maybe it had seen too much action. Popped out the cork filled the system and put on my old cap with new o rings. A quick visit with the in-laws and we were back on the road to seattle. Temps normal the whole way. Stopped half way and no coolant loss. We got home and still no coolant loss. Must of been the new cap right? Has this happened to anyone? I was from Atlantic British. Seems like waterfall has subsided. Any thoughts?