Dang waterfall noise

[gaber6]

Well after the highway drive, I have waterfall at 1500 to 2k rpm again. I keep adding fluid as the engine cools.

I'll sand the seating surface where the cap screws in a little more, but I checked it 3 times and it was good.

I'll pick up an oem radiator cap tomorrow, too.

 

[gaber6]

Seems worse now. The reservoir is filling up as if the cap isn't holding any pressure. The Toyota dealership didn't have any caps in stock, which there are 3 different ones for my model year. Hmm. I have one on order for Wednesday.

Apparently there are 3 different factory caps that go on the 2005 and they used the VIN to get the right one. Maybe why the NAPA caps are failing?

Lucky there is a NAPA nearby and I'll swap out the radiator if the factory cap doesn't work..

 

[ArthurKotb]

[snip....]And the hoses in the tank are good and go to the bottom.
[snip....]
I'd smell it inside if it was the heater core, right? It's just weird that the bubble always works itself back to the back at the heater core to make the noise....
[snip....]
A Tacoma just pulled up and I asked to check the radiator hoses.. his lower has some warmth to it. Mine was cold to the touch after a drive. I'll have to double check that after another longer drive

If the overflow is full and the hoses are in good condition, when the engine cools the radiator should be pulling water from the overflow. If this is not happening and your radiator needs to be refilled by you, then there is a problem. That may be where the air is getting in. That's supposed to be a closed system. Engine gets too warm and coolant goes into the overflow. Engine cools down and a vacuum forms, pulling coolant from the overflow back into the radiator.

If coolant was leaking you'd probably be able to smell it. I can smell coolant if the hoses are leaking. It's such a distinctive aroma. The noise you hear sounds like it's inside the car? That would be the heater core I think. It probably sounds like a squeaking, squirting noise, coming from the firewall.

If your lower hose is cool to the touch after the engine has warmed then you have a blockage somewhere, possibly the thermostat. Both hoses should be hot after a long drive.

 

[gaber6]

No outside leaks for sure. I'm camping on a dusty area and would see anything wet as everything is coated in dust. No smell either like when my HG was bad. Every startup as well as driving with the rear window down was bad. Nothing here and pressure test was good.

And yeah, it's the heater core woosh for sure. I had the thermostat off and it's still like new and not blocked.

What you described is right. The overflow is filling but not sucking back. The hoses are all connected there and the overflow cap is new. It may have something to do with the NAPA cap not sealing properly. So before I return the radiator, I'm trying an OEM cap. Like I said, there are 3 OEM for my year and they are VIN specific which is super odd.

I did feel the lower after a longer drive and it's warm to the touch but by no means untouchably hot like the upper hose.

The temp gauge never goes above halfway so it's not overheating, but the radiator thinks it is.

I'll find out Wednesday when the cap comes in. I really hope it is that simple.

 

[ArthurKotb]

And yeah, it's the heater core woosh for sure. I had the thermostat off and it's still like new and not blocked.

Definitely an air leak and most likely at the radiator cap. With no vacuum it can't suck back the overflow, just air.

When the engine is cold and you open the cap the coolant will be right at the very top and may even spill out. Anything else means an air leak.

 

[gaber6]

Definitely an air leak and most likely at the radiator cap. With no vacuum it can't suck back the overflow, just air.

When the engine is cold and you open the cap the coolant will be right at the very top and may even spill out. Anything else means an air leak.

Pushing down on the cap makes it leak into the reservoir when it's running. There is something for sure wrong with the design.

I also made this to bleed the system. Pill bottle plus Listerine bottle fits almost perfect. Push fit with just a dribble around the edge. Should have the new cap by this afternoon.

 

[gaber6]

NAPA cap vs. oem..
Totally different design and if this doesn't fix it, who knows.

Looks to have an extra check valve that releases in the center to instantly pull back liquid from the reservoir upon cooldown. Has to be the issue. Will update after a couple days once I get it on there.

 

[gaber6]

Three small trips with heat cycles and success.

• Fluid doesn't fill the reservoir when driving.
• Fluid gets pulled back in on cool down.
• Waterfall is 99% gone, and I think with a few more cycles with the proper cap now will be gone soon

.

So if you are using a generic cap, you may want to switch to OEM before you do anything more than around town driving.

 

[ArthurKotb]

Sometimes genuine Toyota is the only thing that will work. You seem to be on the path to happiness.

 

[gaber6]

Sometimes genuine Toyota is the only thing that will work. You seem to be on the path to happiness.

Yea I learned that with my 1st water pump. As the next round of replacement parts go, I'll likely go OEM now that I have no reason to think the engine needs a rebuild.

 

[gaber6]

I burped the radiator for over 30min on a steep incline with a long hose. I let it cool and topped off the radiator.

Went for my drive down the highway and and back and got waterfall at 1500rpm again.

The new cap seems to work fine letting fluid flow both directions on heat and cooling cycles.

This is frustrating. There is still stop leak copper in there so if there were any small leak, it should fix it, but the pressure test held 3 times so what the heck?

 

[gaber6]

I burped the radiator for over 30min on a steep incline with a long hose. I let it cool and topped off the radiator.

Went for my drive down the highway and and back and got waterfall at 1500rpm again.

The new cap seems to work fine letting fluid flow both directions on heat and cooling cycles.

This is frustrating. There is still stop leak copper in there so if there were any small leak, it should fix it, but the pressure test held 3 times so what the heck? When it cools again I'll see if the stop leak clogged the release valve. Might have to flush the system if that's the case.

Ok car cooled and didn't suck the coolant back in. There is a slight area of stop leak on the rubber gasket.

I cleaned it up and moved the coolant from the overflow to the radiator. I am still skeptical that the neck of the radiator is misshapen from the factory where it had dings and initially didn't seal at all. I guarantee I still will have a waterfall sound on startup tomorrow

 

[gaber6]

Interesting...

I decided to get a second can of stop leak now that I have a correct radiator cap. Just for giggles, I unplugged the drivers rear coil pack to reduce pressure {as that was the offending cylinder at 150k miles)

When idling up to temp, I noticed right away the lower hose had pressure now, which is interesting. Prior even when fully warm, I could squeeze the lower pretty easily.

Does this mean the new sealant will take hold? I dunno. Maybe long enough until I have a shop to do a proper repair. I'm doing two full warm cold cycles from idle tonight then my drive up the highway tomorrow.

 

[gaber6]

Before my ride this morning, I tried to burp out the air from the heater core, but didn't quite get it. No more bubbles were coming out so that seems like progress.

My ride down the mountain to town results in still 1500rpm waterfall, same as back up the 3 or 4 mile steep grade. At the bottom, after a round of golf, I used my antifreeze tester to scoop about 4 bulbs of coolant from the tank into the radiator.

I'm back idling now with the middle cylinder coil pack unplugged to see if that might get it.

 

[gaber6]

Hmmf.

Cooled down and didn't suck coolant back into the radiator. Was about 10 bulbs worth to move from the reservoir back to the radiator. About 1/4 to 1/2 cup.
I'm not losing coolant out the tailpipe or anywhere. No smell. I'm baffled.

Back to thinking the neck of the radiator isn't sealing the cap properly so as it cools it's bringing air in. I might try some flexible caulk I have all around the cap temporary on my next drive to see if that isolates the issue.

 

[gaber6]

Ok bear with me here.

I'm going to run into town again and get a stupid combustion gas test kit, but also some new hose for the reservoir.

The syphon hose I noticed has gotten swollen, so despite having a small clamp on the inside to hold it, the volume of the tube is way bigger, so theoretically, it may be having trouble bringing the fluid up.

 

[gaber6]

Good news.

The combustion test kit with fluid is a rental at O'Reilly. I also added new smaller diameter hoses to the overflow and the siphon.

Here are images from 2 tests over the course of 5 minutes. Doesn't look like it changed at all, which is consistent with the pressure test holding 15psi 3 times.

I'm going bonkers here.

 

[gaber6]

Returned the tester in town today down the mountain.
I haven't burped the recent air out in a few days, but I'm ok with waterfall as long as the radiator pushes and pulls coolant on heat cycles.

Checked the level after coming back up the mountain this morning and fluid didn't push out half an inch or more into the reservoir like it has been, so there's a SLIGHT chance it was the overflow hoses being old. I go go a longer drive tomorrow while pulling my camper, so that'll be the real test.

 

[gaber6]

• New thermostat
• Newer hoses
• 3 new radiator caps
• Newer radiator
• Toyota coolant
• New plugs
• New transmission cooler
• New overflow hoses
• NOT overheating
• Blue combustion test stays blue
• Compression on each cylinder 120psi
• No coolant leaking
• No coolant in oil
• No coolant smell from exhaust
• Newer fan clutch
• New waterpump

Yet it still is making air in the system. I'll be back in Ohio where I have a garage to work and might just have to do the HG and machine the heads this time. That was a mistake not to.

 

[gaber6]

I picked up a bigger, more expensive stop leak earlier today with a different chemistry.

It was more of a gel as it poured into the radiator. I idled it up to temp for 30 minutes or so and got both hoses warmed and flowing.

A few minutes after cooling off, the hoses actually were pliable. Prior to this application, the hoses held air pressure after cooling a bit, but still warm, thus not pulling coolant back.

I know it seemed like a HG the whole time, and I sorta expected it either right away when I put the new HG on at 150k miles or they'd hold. At least if this holds, I know I can fix it for $30 until I want to bust my knuckles.