Coolant loss from expansion overflow

[123kendale]

2008 avensis eat 2.0d D4D T2.....loosing coolant only ever 2 litres from expansion tank overflow when engine gets to operating temp on longish high mph journeys round town short journeys doesnt happen car has had new cap and thermostat DEFINITELY not head gasket...please help ankoying to keep topping up thanks

[Mike169]

Hi Eason and welcome to the club.

May I politely ask how you know it is definitely not the head gasket?

Mike.

[Byzii]

Also when do you top up the tank and how much? In my 2004 1CD-FTV the coolant reaches FULL mark when engine is completely warmed up, but when the car is cold the coolant is a little bit above the LOW mark. If I top up the tank while the engine is cold to the FULL mark then the extra coolant leaks from the overflow tube.

Don't know if this is normal but that's how it is on my car. Might be a similar problem.

[Mike169]

Hi  Byzii or is it Edwards?

First of all 'hi' for the first time, your car sounds normal to me with nothing to worry about.

Mike.

[Guest]

Assuming your not loosing fluid though a leak somewhere else, (and assuming your exhaust isn't showing signs of water vapor during combustion), double check the RAD cap(even if new).

If its the wrong pressure rating, faulty, or an ebay-china special, it could explain it. Not all caps are equal. Quite the opposite.

I just had nearly Identical problem on my car that i solved with a new and better rad cap - Granted my car is world and lifetime apart from a avensis, the principle and rad tech is still the same.

Phil from the  MKiV supra owners club explained the basic problem quite well (12 Years ago!?!? so depressing 😞 )

Name:
Losing coolant from the reservoir bottle

Also known as:
Losing coolant
Overflow bottle is always empty
Expansion tank

What is it?
The overflow tank of the coolant system isn't in fact an overflow tank - it's the expansion tank or coolant reservoir. When all components of the cooling system are functioning correctly the level of fluid in the reservoir will rise and fall a small amount as pressure in the system fluctuates. Once the engine has stopped and the water pump ceases to move water round the system and the forced cooling effect of the radiator ceases, there is a temporary rise in the fluid level in the reservoir bottle. As the system cools, coolant is drawn back into the system and the level of coolant in the reservoir will return to its original position, usually the max mark on the bottle.

If you are losing coolant, each warmup-cooldown cycle will empty the expansion tank further until it's dry.

Usually caused by:
The most common cause of fluid loss is a faulty radiator cap. 

Why?
If you have a faulty cap it cannot sustain the pressure of the system and allows extra fluid to be transferred to the reservoir bottle. Under driving conditions the cooling effect of the radiator may be sufficient to counteract the reduction in pressure caused by a minor fault in the cap. However, once the car is stationary the radiator may not provide enough cooling to prevent the coolant level from getting so high in the reservoir bottle that some coolant is vented off from the reservoir cap. In a hot engine with the stock fan running any released coolant will fall onto the under tray and will quickly evaporate. When the ignition is switched off, no further forced cooling is possible with the stock fan. With a faulty radiator cap and the vehicle park on level ground or facing up hill, any vented coolant will not be visible as it will fall on to and be absorbed into the tray. 

With a mildly faulty cap this venting of coolant will continue at each period of use until the cap is replaced. If the cap is not replaced the coolant the in reservoir will fall to a level that is below the mouth of the return feed to the radiator and air will be dawn into the system. However if the reservoir is checked when the vehicle is warm the level of coolant visible may look normal as it takes quite some time for the system to cool sufficiently to draw coolant back from the reservoir. Left unchecked the system will continue to vent fluid when ever the pressure in the system becomes higher than the faulty cap can sustain. Visual checks of a hot may lead the owner to mistakenly believe all is well.

How bad is this problem?
If you overheat your car due to lack of coolant, it can reach new-engine-time levels of seriousness. However, just having an empty reservoir tank isn't the end of the world. No damage is done until the car actually overheats, so fill it back up and replace the rad cap sooner rather than later.

Other possible causes: 
There are other more serious reason for the car to lose coolant, a leak at the head gasket or a failing or loose hose connection. By checking your cold coolant level regularly you will soon spot a sudden change and prevent more potentially serious engine problems.

-Phil

[123kendale]

2 hours ago, Mike169 said:

Hi Eason and welcome to the club.

May I politely ask how you know it is definitely not the head gasket?

Mike.

Hi...all signs to check for head gasket failure are not present at all

[Mike169]

Hi Eason.

Has the car had a 'sniff' test at a garage, any garage will know what that is?

Something like this:  https://www.ebay.co.uk/itm/BT-2-COMBUSTION-LEAK-TESTER-KIT-CO2-HEAD-GASKET-PETROL-BLOCK-TEST-FLUID-17d-/272706534162?clk_rvr_id=1599996717111&utm_medium=cpc&utm_source=twenga&utm_campaign=twenga&utm_param=eyJlcyI6MCwicyI6OTcyMDIzNywiY2kiOiIwMzMzYTQ3MThiOGM1YThmMjIyYTc1ZTJkNzRlZWJiZCIsImkiOiIxMTc1MjQ0ODQ1NzY5NDk3MjUwIiwidHMiOjE1MzE3NDY4NzQsInYiOjMsInNvIjoxNTAwLCJjIjoxNzk0ODZ9&rmvSB=true

Mike.

[123kendale]

12 minutes ago, Supra_knight said:

Assuming your not loosing fluid though a leak somewhere else, (and assuming your exhaust isn't showing signs of water vapor during combustion), double check the RAD cap(even if new).

If its the wrong pressure rating, faulty, or an ebay-china special, it could explain it. Not all caps are equal. Quite the opposite.

I just had nearly Identical problem on my car that i solved with a new and better rad cap - Granted my car is world and lifetime apart from a avensis, the principle and rad tech is still the same.

Phil from the  MKiV supra owners club explained the basic problem quite well (12 Years ago!?!? so depressing 😞 )

Name:
Losing coolant from the reservoir bottle

Also known as:
Losing coolant
Overflow bottle is always empty
Expansion tank

What is it?
The overflow tank of the coolant system isn't in fact an overflow tank - it's the expansion tank or coolant reservoir. When all components of the cooling system are functioning correctly the level of fluid in the reservoir will rise and fall a small amount as pressure in the system fluctuates. Once the engine has stopped and the water pump ceases to move water round the system and the forced cooling effect of the radiator ceases, there is a temporary rise in the fluid level in the reservoir bottle. As the system cools, coolant is drawn back into the system and the level of coolant in the reservoir will return to its original position, usually the max mark on the bottle.

If you are losing coolant, each warmup-cooldown cycle will empty the expansion tank further until it's dry.

Usually caused by:
The most common cause of fluid loss is a faulty radiator cap. 

Why?
If you have a faulty cap it cannot sustain the pressure of the system and allows extra fluid to be transferred to the reservoir bottle. Under driving conditions the cooling effect of the radiator may be sufficient to counteract the reduction in pressure caused by a minor fault in the cap. However, once the car is stationary the radiator may not provide enough cooling to prevent the coolant level from getting so high in the reservoir bottle that some coolant is vented off from the reservoir cap. In a hot engine with the stock fan running any released coolant will fall onto the under tray and will quickly evaporate. When the ignition is switched off, no further forced cooling is possible with the stock fan. With a faulty radiator cap and the vehicle park on level ground or facing up hill, any vented coolant will not be visible as it will fall on to and be absorbed into the tray. 

With a mildly faulty cap this venting of coolant will continue at each period of use until the cap is replaced. If the cap is not replaced the coolant the in reservoir will fall to a level that is below the mouth of the return feed to the radiator and air will be dawn into the system. However if the reservoir is checked when the vehicle is warm the level of coolant visible may look normal as it takes quite some time for the system to cool sufficiently to draw coolant back from the reservoir. Left unchecked the system will continue to vent fluid when ever the pressure in the system becomes higher than the faulty cap can sustain. Visual checks of a hot may lead the owner to mistakenly believe all is well.

How bad is this problem?
If you overheat your car due to lack of coolant, it can reach new-engine-time levels of seriousness. However, just having an empty reservoir tank isn't the end of the world. No damage is done until the car actually overheats, so fill it back up and replace the rad cap sooner rather than later.

Other possible causes: 
There are other more serious reason for the car to lose coolant, a leak at the head gasket or a failing or loose hose connection. By checking your cold coolant level regularly you will soon spot a sudden change and prevent more potentially serious engine problems.

-Phil

Hi supra-knight.....tried eBay cap lol no good..so went to Toyota and one supplied by them EXACTLY the same as the eBay one for 3 times the price and there are definitely no leaks from anywhere else....hose from thermostat housing back to rad nowhere near as hot as the hose from rad into the system

[Guest]

11 minutes ago, 123kendale said:

Hi supra-knight.....tried eBay cap lol no good..so went to Toyota and one supplied by them EXACTLY the same as the eBay one for 3 times the price and there are definitely no leaks from anywhere else....hose from thermostat housing back to rad nowhere near as hot as the hose from rad into the system

Unfortunatly thats means things have to get more serious in consideration.

Water doesn't just dissapear.
Its getting out somehow, and there is really only 3 main ways.
1- Evap from the expansion tank, 2 - Leaking from a pipe, part, connector, etc...., or 3 - its getting into the cylinders and being passed out the exhaust.

1 -The cap is now ruled out, next step
2 - Leaks - If the cap is ruled out, you want to start looking for leaks. They can be very hard to spot , as if its  small slow leak, it could be evaporating off before showing any clear signs. If you have red coolant, you should see some sort of pinkish staining somewhere if this is the case,. If you cant find any leak in or around anywhere, such as the rad itself, poor connections, water feed lines, water pump, etc... and your absolutely sure there is none -then its onto the next step. But believe me, those leaks can be damn hard to find, and you WANT to find this ...because its much better than the next step. Professional Mechanics are usually excellent at finding leaks quickly because of their experience. Home mechanics like me take forever to find them.
3-  If Leaks are ruled out - now you have to start looking at the possibility of water getting into places it should not, in particular the head gasket. If its a "small" head gasket leak(if there is such a thing) it will very likely get worse soon. You may not notice much water vapor out the exhaust now, but it could be an emerging sign and getting worse. Also look for emulsified oil. Thats when oil and water have actually mixed. Looks like a off white milky sludge - Thas BAD. Look in the oil cap and the dipstick for signs. Also start the engine without the rad cap and look for bubbles in the coolant, which could indicate gas is also escaping and passing into the coolant chambers. A head gasket is an urgent fix if identified, so you shouldn't even start the car if looks to be the case. Its also a horrible job to do as-well, hence the high labor costs for it.

The only other freak/fluke chance I can think of is what I've sen before back in Australia. Someone I know flushed their Coolant system  out for maintenance, and didn't put anywhere near enough back in. How the hell the engine ran and didnt overheat I don't know, but they were complaining about topping up the expansion tank for weeks until they realized. by then it had the correct amount in it, and the expansion tank was no longer emptying itself and running dry all the time. Had it been an Aussie summer, Id say it would have been a lot worse for them.

 

[Heidfirst]

are you sure that it is being lost from the expansion overflow? If not check for weeping water pump.

[123kendale]

I have previously topped up the expansion tank, ran the car with  the accelerator at normal revs till the temp got to normal level and then got out went to front of car to look for leaks had jacked the car up and removed the under engine cover.

By the time i had got out and got to front of the car there was water all over which had only come from the expansion overflow...There is definitely no milky sludge in oil filler/dip stick.  The water loss is definitely only coming from the overflow expansion pipe.

Is it possible my new thermostat is only working intermittently?  it was removed and tested after installation in boiling water and did open and close!!

Is there a "proper way" to refill a car after its drained i.e. when i put the new thermostat in? Could I have an airlock somewhere if so how to remove?  Currently i am only topping up with water not coolant which seems pointless

Appreciating everyone's help and suggestions

[JontyP]

I found this thread researching the very same problem on my 2008 Corolla Verso 2.2 D-4D. I asked the main dealer whom I bought it from and has done all the servicing to check it out. They pressure tested the cooloing system and did some sort of chemical test on the coolant that detects exhaust chemical traces. Bad news, they say it it is definitely the head gasket beginning to leak.

Have given two quotes, one to repair and the second for a Toyota supplied recon engine. Not much difference in price.

Would appreciate views on which way to go.

JP

[Mike169]

Hi Jon.

Between 2006 and 2009 Toyota made only a few bad 2.2 diesel engines within those years. Basically they got an internal measurement/tolerance too tight and when carbon built up on the pistons it would blow the head gasket. Within a certain time period or within just over 100,000kms or 7 years I believe it was whichever came first Toyota would change the engine FOC. Now i'm afraid it's down to the owner and even Toyota dealer repaired engines used to fail again so it became their own practise to either change the whole engine or a short block re-using your existing cylinder heads. As the price is very close I don't think it's an option, go for a new engine, that way you will get an engine with slight internal differences and that makes all the difference. Then the invoice would be around £7000.00, obviously I don't know your quotes but that's the way I would go.

Good luck, Mike.

[JontyP]

Mike, very helpful thanks. Just wanted to clarify, when you say go for new engine, do you include what the quote refers to as N/STOCK REMAN AD ENGINE (T19000-0R061-84) which I understand to be a Toyota rebuilt in Japan engine. The quote I have for that is about £3.700

 

Thanks

 

Jon

[Mike169]

Hi Jon.

As I understand it, as I didn't have a Toyota 'then', if you took your 2.2d engine car, I say car as the same engine went into many models, the £7000.00 quote is for a brand spanking new engine off the production line, not a re-con that includes labour/fitting as well. I have read many stories of where 'back street' and main dealer garages fitting just new head gaskets or even total rebuilds but they failed again so Toyota  went down the route of just fitting new engines as the internal dimensions were/are different. After 2009 all 2.2d engine's made were the newer spec and incidentally these were the 180 power ones not the newer 150 one's. A man I highly suggest you call is a top Toyota main dealer parts man nicknamed Kingo also Parts King, he is on this site 

https://www.toyotaownersclub.com/profile/34014-parts-king/        

Above is his profile and his real name is John Devlin and his phone number is 01978 720074, I have contacted him several times and he is always helpful and polite and gives good advise. If you buy parts from him you always get a good price, discounted. So if and when you call him you will have to go through a main switchboard but they can put you through to him. You are welcome to say I gave you all his details and if I was in your very unfortunate situation I certainly would chat to him, he may even be able to help you with a new engine at a good price. So for a 100% accurate price just phone him, tell him you are on a thread on this site and you have sought my advise and I recommended him. Even if you only want parts, filters or whatever I am sure he can help you and may I suggest you store his phone number in your phone, you'll need it again probably. If he is on holiday or anything find out when  he return's for his advise.

It's been a pleasure to help you out, Mike.

 

 

[JAke d]

Is there any other  explanations Why my d4d is pressuring up blowing coolant out of the overflow, 

new

head gasket 

water pump 

thermostat 

rad cap 

timing kit 

 

 

[FROSTYBALLS]

Moved to the Avensis club.