Loss of coolant

[chalkyuk]

Help!!!

I have a 2011 1.8 avensis estate, 134,000 miles. Recently it has started losing coolant. No visible signs anywhere and no coolant in oil, no oil in coolant. No puddles or anything under the car ever. The car is going in tomorrow  for pressure testing but I'm at a loss. I'm not a car person so have no ideas. 

When I say losing, it's about 1/2 litre in around 2 weeks. It had a new clutch on November, gearbox bearings 3 weeks ago along with new slave and clutch master cylinder. 

Praying it's not head gasket.

Any ideas are greatly appreciated 

[yossarian247]

Pinhole leak in the radiator perhaps? If coolant leaks anywhere that's usually hot it can evaporate before it has time to form a puddle etc.

Assuming your talking about the 1.8 petrol engine? The petrols are not known for head gasket problems

[chalkyuk]

Yeah it's the 1.8 petrol. Anyway of checking the radiator? Don't want to just start replacing things it 'might' be 

[Konrad C]

It could be anything. I would not be surprised if a hose has been damaged or not reconnected properly, with the amount of work carried out. The car seems to have done a lot of miles and had a hard life in a short time. The clutch change expected for the mileage. 

The next item if not the hoses and connections is the water pump. Given the hard life, I would say that is due for a change. When the seals start to fail on a water pump, you get a small drip and then it evaporates very fast. The only time you can spot a leak is during warm up and cool down when the metals expand and contract. Since the engine has an under cover it is not as evident. Then there is the radiator. That could be damaged by a stone through the grill. I noticed how vulnerable the radiator is, and was thinking of installing a wire mesh.  

Hopefully the test will reveal the cause, and it is not the head gasket. Head gasket is normally rare for this engine, especially for a Valvematic engine.

Don't use any stop leaks, if the actual source of the leak is discovered.

I have noticed another reply mentioning the radiator as I was typing this. 

[yossarian247]

If coolant is leaking you should be able to see staining near the source of the leak from the antifreeze residue that's left behind after the water has evaporated. It can be a case of looking carefully around the rad and all of the coolant pipework for signs of this. The difficulty can be seeing all around the radiator as parts of it are quite well hidden on most cars.

[chalkyuk]

Thank you both. I was leaning towards the water pump (although I'm not sure where it is lol) but hopefully the test tomorrow will find it easy enough.

[Konrad C]

The water pump is located below the alternator. It might be wise to change the belt at the same time. 

Here is an video and the engine is basically the same, but without the Valvematic system. 

After seeing this video, I now know what to do if the water pump ever needs changing. 

[Anthony Poli]

If your leak was like the one i had on e corolla verso, it would only leak when driving over the heavy duty speed bumps at work. The local dealer didn't find the leak the first time when pressure testing, but found it on the second time. I had gone on holiday and did 800 miles without loosing a drop, but going 3 miles to work i lost 200ml a day.

[chalkyuk]

I'm a taxi driver hence why so many miles on the clock. Topped it up last night and been working 8 hours today and hasn't moved lol. 

Would it make any difference if I was towing a caravan ? ie would it leak quicker? I know that might sound stupid but that's how I noticed it was low again yesterday 

[chalkyuk]

1 hour ago, Anthony Poli said:

If your leak was like the one i had on e corolla verso, it would only leak when driving over the heavy duty speed bumps at work. The local dealer didn't find the leak the first time when pressure testing, but found it on the second time. I had gone on holiday and did 800 miles without loosing a drop, but going 3 miles to work i lost 200ml a day.

Where was your leak when they found it? 

[Anthony Poli]

Sorry i forgot to say, it was the radiator itself. When you were stood over the radiator and looking down,  the coolant seemed to be dripping between the middle and the lower hose outlet. it did drip onto the ground when parked, after going over a speed bump and then stop until the next speed bump.

[avensisd4d786]

follow konrads advice,
hoses,
waterpump- if it hasnt been changed before would be a starting point at 134k.
radiator

[chalkyuk]

Update.

Car was in today.  No leaks found anywhere so has to be head gasket. Mechanic found that some water was coming out of exhaust meaning the leak must be in to the combustion chamber. The leak has to be tiny as only losing coolant slowly. 

[Konrad C]

On 6/22/2016 at 0:35 PM, chalkyuk said:

Help!!!

I have a 2011 1.8 avensis estate, 134,000 miles. Recently it has started losing coolant. No visible signs anywhere and no coolant in oil, no oil in coolant. No puddles or anything under the car ever. The car is going in tomorrow  for pressure testing but I'm at a loss. I'm not a car person so have no ideas. 

When I say losing, it's about 1/2 litre in around 2 weeks. It had a new clutch on November, gearbox bearings 3 weeks ago along with new slave and clutch master cylinder. 

Praying it's not head gasket.

Any ideas are greatly appreciated 

 

9 hours ago, chalkyuk said:

Update.

Car was in today.  No leaks found anywhere so has to be head gasket. Mechanic found that some water was coming out of exhaust meaning the leak must be in to the combustion chamber. The leak has to be tiny as only losing coolant slowly. 

Did the mechanic do a proper sniff test? Surely if any coolant got into the combustion chamber, gasses from the combustion will get into the cooling system. My car had a lot of fluid in the exhaust due to lack of use. This affected the Lambda reading on the emission test, plus the MOT tester had to drain the exhaust fluid catcher twice!

Let me get this straight. 1.8 Valvematic 2ZR-FAE engine estate with 134,000 miles from 2011. Transmission and clutch already rebuilt. The car must have had a very hard life. That means the car would need to be serviced four times a year, going by the 10,000 miles or annual, which ever comes first! 

That is oil change each time and coolant and transmission fluid, a year or two. I would imagine the brakes being changed more often too.

My old '98 Avensis was at 147,000 miles when I recently sold it, and during most of it's life, had two oil changes a year, and the coolant changed every 2 years. I also did a couple of transmission fluid changes. The transmission was changed at around 130,000 miles or so. Transmission seems to be a weakness of Toyota's.

Normally the 2ZR engine is fine for high mileages, so long as the regular services are done. Look at the Toyota Prius which uses a variant of the same engine.

What I would do is go through every connection in coolant system as possible, and also make sure there are no airlocks in the system. That involves squeezing every hose to force any air out. Then monitor the system for loss and discoloured coolant.

I will repeat, get the coolant sniff test done, and go from there.