Pajero Owners Club of South Africa

Hi to the really clever technical experts! I have send my Pajero 3.2 DID, 2005 for a routine service @190,000 km. 2 hours later I received a call from the workshop manager that something is wrong with my engine. See attached photo's of evidence and symptoms. The engine never overheated, nor smoked and had no loss in power. The workshop manager is convinced that gas created the bubbles/sludge (which is not oily by the way).
The top was removed and tested - noevidence of head gasket problems and no leaks were found with pressure test on top. They wanted to dig deeper (cylinder head ect) but I stopped them.
What could this be? My guess is that somehow soap water got into the radiator at the petrol station. Unfortunately the workshop manager did kept water samples and did not send it for testing.

I will really appreciate expert opinions! Regards

Hi,
Certainly not 'normal'.
Whatever is in there creating the foam needs to be removed.
Take a teaspoon and spoon some of the foam into a glass, add tap water & see what happens. If the foam dissolves then whatever is causing the foam is water soluble (best option), if the foam doesn't dissolve then it is probably caused by a water / oil reaction.
If the foam is water soluble then add fresh water, run the engine until the temp gauge moves to normal (ie the thermostat has opened) then switch off & drain. Repeat this process until the drained fluid is clean & clear. This is to get rid of any residual contamination. Finally, refill with the proper mix of coolant.
If the contamination is oil based then you need to find out where the oil has come from. This is unlikely as the cooling system is under pressure when the engine is at operating temperature & this pressure will force water into the oil (the pressure test has effectively ruled this out already).

If your guess that soapy water was used to top up your cooling system is correct, then you need to get rid of it ASAP so that pump seals etc are not compromised.

Hope this helps
D

Looking very weird. As you said, it doesn't look like there is oil in it.
Your assumption that it was a mistake made a the petrol station sounds right to me. Could be the water they use to clean the windows. That's why I never open the hood at a petrol station!

You could try to disconnect the lower radiator hose, and have a constant feed going into the engine (hose pipe) in order to rinse it whilst running.
Sounds like your mechanic jumped the gun a little bit there stripping the head...

Please keep us posted if you have more details on what caused this.

Thanks,
Fab.

Hi Fab and DandB,
Thanks for your postes, much appreciated. I was waiting on some replies before giving more information as I was hoping that the same happened to cars of other club members. The mechanic who serviced my car is a reputable mechanic and he also got a second opinion. Both of them was convinced that the top gasket has gone and therefore the engine was taken out and send to the engineering shop to remove and test the top. The top tested good, no evidence of any leaks or cracks. Unfortunately only at this stage I saw the pictures of the radiator and foam. I instructed the mechanic and engineering shop to stop any further stripping and asked them to put the top back with new bolts and gasket. I also asked that the radiator need to be flushed and tested. Just like Fab mentioned I was convinced that the mechanic jump the gun by taking the engine out before doing more tests.
With hind sight and only seeing the pictures after the engine was removed, my 1st reaction was why didn't the mechanic flushed the radiator and filled it with clean water and run the engine or do the bottle test to see if gas is entering the cooling system. I asked the mechanic why he did not do it, and his answer was that he did the bottle test and it was clear to him that gas was present and convinced that the top gasket was leaking.
Unfortunately it was too late for asking for water samples or that it need to be tested before taking out the engine as the mechanic convinced me that the top or top gasket is faulty.
Even after I have instructed them to put the top back, they kept on looking for the gas leak and pulled the pistons and put the block on the milling machine and found that the block is warped and therefore the reason for gas leak. They could not give me a reading by how much the block was warped, but send me the attached pictures, showing the bright machined areas and darker areas which is lower (not sure by how much, but understand that 0.1 mm is the limit).
I am now waiting for them to skim all facing areas and put everything back. I still do not know what the total cost will be and I am still convinced that nothing was wrong with the engine. If the top tested good, but the block is warped then somewhere in the past the engine must have overheated badly. The car is driven daily by only my wife and myself and none of us can recall any overheating or water loss. It could be that we never saw the temp gauge or that this the 1st time that it ran without water on it way for a routine service (what is the chances??).
I will appreciate comments from the experts. My questions is, what is the possibility is that a block can warp and can cause top gasket failure with the top not being warped or cracked and cause the type of foam in the radiator as per the pictures.

Thanks

I never had to deal with a warped block, but my opinion is that an aluminium head will sustain considerable damage before the block warps.
So your theory of a previous over heating would make sense, where a new head might have been fitted.

You can see on your last picture that there is some black silicon sealant between the block and the aluminium cover bolted onto it on the right hand side. To me it says that this engine has been opened before.
Another tell-tale sign would be scribes on the head, numbers on the injectors, etc...

From what I've read on this forum about DiD failures is that they are never the same after they've been rebuilt.
I hope you'll come right.
Keep us posted.

Fab.

Hi Fab,
I bought the car brand new in 2005, and this is the 1st time that the engine was opened. 190,000 km to date

I'm not too sure what to say!
The plot thickens...

I tried to comment earlier and got side tracked. Sorry.

I agree that nothing except a contaminant would cause the foaming. Question is where from. Ok but not the problem right now.

The real problem: Let me read this a couple of times over so I can think about this.

Engine is assembled. OP should have got his car back. I am sure he will comment shortly.

Such clean white foam emanating from engine gases, I'm surprised.

Looks more like windscreen washer fluid has been added to the radiator expansion reservoir.