Why does 93Camry V6 dump all my coolant when hot ???

[jopki]

Hello, I was wondering if any of you have seen this kind of behaviour:
93 Camry V6, 270K, I believe 3VZFE engine. When running for a while at normal temp, full of coolant, the engine expels up to about 3L of coolant through a small rubber hose which looks like an overflow from the expansion canister and starts overheating. This continues even after engine is turned off. I found identical symptom on youtube:

You Tube

You Tube

. This could be my car, by the behaviour. This started happening after 3 wks of not using the car.

In order to remedy this situation I have had the thermostat exchanged, I glued a small radiator leak at the very top near the radiator valve cap, replaced this rad valve cap (new one), checked that there is no other place where the system drips coolant. Rad fan does turn when it gets to a decent temp but not overly fast. I am suspecting that perhaps the other valve cap (the one I did NOT replace) which is the coolant filling port sitting on the block just next to the top rad hose - may not seal properly and the fact that I glued a small hole in the rad resulted in big enough increase in pressure that the old coolant refill valve opens and ejects the coolant.

My mechanic says however that the problem is likely a blown head gasket pressurizing the coolant system. I brought my car to Toyota dealer/service to give me a quick estimate but the guys who normally change oil there were turning their heads - haven't seen anything like that... Any ideas?

Thanks for any insight
JE.

[Jimnist]

Is the overflow tank full or is just just passing through the hose?

When you say radiator valve cap, you mean the radiator cap at the top of the rad, right? Did you bleed the radiator system properly? Those are some simple things i'd get on top before trying anything else.

I've never seen a blown head gasket do something like that(then again, i haven't seen a lot of things lol). If anything, it would mysteriously disappear from it getting burnt and passed out the exhaust as steam. Do you notice a lot of steam coming from the exhaust after the engine is warm/been on a drive? A good way to tell if the HG has blown is to do a compression test and leak down test. Leak down is much better.

[jopki]

1. The overflow tank is surprisingly only half full, when it gushes out of the tube.
2. By "Radiator valve cap" I mean the rad cap on the top of the rad, (which says "not a Refill port")
3. I filled it through the "Refill port" cap which is the one close to the block, on the other side of the top rad hose than the rad itself) as much as I could, both caps open ran the engine and add more coolant as bubbles came up and level dropped, until it appeared full at about normal temp, closed both caps.
4. There is NO steamy exhaust, it doesn't burn coolant. The theory being that the engine pressure pushes through the gasket hole towards the cooling system... what is a bit odd is that it does it only when overheated. - This would almost indicate to me a cracked head which expands the crack when hot. that would be even worse...
thx, JE.

[93XLEcamry]

not a pro, but im guessing your head gasket is going.....same thing happen to mine a few months ago....then a week went by and one day started the car and out the exhaust came all the coolant....maybe its not too late for you, but i hope its not a hg problem...good luck bro..

[chronoti]

well dose your coolant look milky?

no?

then not bhg.

try replacing the other cap.

[Jimnist]

Originally Posted by chronoti

well dose your coolant look milky?

no?

then not bhg.

try replacing the other cap.

If you have a BHG, coolant doesn't always go milky/ engine oil turn into a milkshake. It only happens if it breaks or blows between a oil and coolant passage

[khanhstar]

i got the same stupid problem. had it checked out not a BHG or even close. so..... fill me in when you know what it is ok.

[chronoti]

well to be a bit more clear

Originally Posted by jopki

... I glued a small radiator leak at the very top near the radiator valve cap, replaced this rad valve cap (new one), checked that there is no other place where the system drips coolant. ...
My mechanic says however that the problem is likely ... pressurizing the coolant system.

Originally Posted by jopki

... perhaps the other valve cap (the one I did NOT replace) which is the coolant filling port sitting on the block just next to the top rad hose - may not seal properly and the fact that I glued a small hole in the rad resulted in big enough increase in pressure that the old coolant refill valve opens and ejects the coolant....

springs fatigue after a while especially when emerged in hot liquid.

[JohnGD]

Blown head gasket.

This can be verified using a chemical test kit. Or putting a hydrocarbon sniffer near the radiator neck.

[Hajoca]

is the expansion tank tubes hooked up correctly?

[jopki]

Originally Posted by Hajoca

is the expansion tank tubes hooked up correctly?

I never changed it so I assume it is hooked up correctly but I will now double check the tubes and caps

[jopki]

Thanks, chronoti, for posting the picture. This is indeed an area of my suspicion, especially the lower sealing gasket because I had to reconstruct part of the lower sealing seat with a special epoxy putty while fixing the weird-located rad hole...The hole was I thought I did a decent job but will now make sure that the liquid is NOT escaping through the overflow tube coming from the rad valve cap but from the overflow tube coming from the re-fill valve cap at the other end of the upper rad hose.

[jopki]

The rad hole (assumed fixed) was located between the lower sealing seat and was stretched along the top body of the rad, about 0.5 cm length, 1 mm width, right under the bottom of the filler neck as it sits on the rad. So the leak was both external as well as affecting the overflow seal. (Almost as if the rad started splitting at the very top, into 2 halves, right under the neck. One thing is certain: By fixing the "external" rad hole portion, the cooling system must be now more pressurized... perhaps to the point that the other cap valve opens...? I will make abolutely sure I know which overflow hose coolant comes from, they join in a T close to the expansion canister.
Sorry, I am now aware that I made 2 assumptions:
#1: That I fixed the rad and fitted a new cap and it was sealing well - will verify
#2: I believed that when I saw my mechanic investigating, he disconnected the overflow hose leading from the other cap and that was the place the coolant was gushing from. Now I am not sure anymore - will verify. The movie shows the end of the hose behind the T so I am not absolutely sure which cap valve opens when I see the problem.

[jopki]

If I remove both caps and run the engine until warm, is it normal to see coolant explosively gushing out to about 10cm height out of the refill neck?

This was the reason my mechanic deduced it must be blown head gasket.
(he did replace the thermostat)

[jopki]

Thanks, JohnGD. I think that is the only conclusive test I can do. I will look what kits they have at our CT stores.

Originally Posted by JohnGD

Blown head gasket.

This can be verified using a chemical test kit. Or putting a hydrocarbon sniffer near the radiator neck.