2009 D4-D

[TomdeGuerre]

2 hours ago, NORTHERN_LAD said:

If you haven't bought it yet you could get a Toyota dealer to check the reg number to see if the engine has been changed. 

I read on here a while back that the Toyota dealer didn't change the new engine number in the log book if they changed the engine, Toyota said that was the owners responsibility to notify the change to the DVLA. So if you're going to quote your engine number to a Toyota dealer better read off the actual engine number first.

[Ogster]

It seems then there are two conclusions

1 The liklihood of serious failure is relatively low.

2 I cannot do much to prevent failure from happenning anyways.

Therefore, I am not about to worry....much.

Incidentally, why this apparent need to replace the engine if things do go wrong? If oil leaks into coolant - or vice-versa - then a change of the head gasket and perhaps a head skim would most probably cure this. My local independent garage would do this for about £600...

 

 

[philip42h]

Heidfirst / Scott has already outlined the precautions that you can take:

• Short, stop-start, journeys will tend to increase the likelihood of failure; longer runs that allow the engine to fully warm up and regeneration cycles to start and complete within a single journey will tend to reduce the likelihood of failure. So a regular burn down a motorway would be a good thing. If you are using the car solely for short journeys around town you might want to consider swapping to something better suited to that role.
• The use of premium fuels with additives to ensure a cleaner burning engine (or diesel additives to achieve the same effect) rather than 'standard' diesel will tend to reduce the likelihood of failure.

For the details of the problem it's probably best going back to the original, long, thread, but as I understand a blown cylinder head gasket is 'merely' a symptom of the problem. Changing the head gasket only addresses that symptom - the fault will still remain. The Toyota solution is to provide a 3/4 engine that includes modified components ... I believe.

[Ogster]

Those precuations apply to almost any diesel and I take them anyways - apart from adding diesel additives which IMHO are at best not proven.

Causes of HG failure usually do not necessitate an entire engine changeout. Usually it is attributable to overheating, poor mating surfaces between block and head, installation of HG errors. All of these can - usually - be dealt with without the need to replace the engine.

 

[NORTHERN_LAD]

1 hour ago, philip42h said:

 

For the details of the problem it's probably best going back to the original, long, thread, but as I understand a blown cylinder head gasket is 'merely' a symptom of the problem. Changing the head gasket only addresses that symptom - the fault will still remain. The Toyota solution is to provide a 3/4 engine that includes modified components ... I believe.

I think the problem originated with the Pistons / rings which allowed oil to pass into the cylinders causing carbon build up on the Pistons which in turn damaged the head and gasket. As not all engines suffered it may have been an engineering problem. 

The test applied by Toyota was to fill the oil to the correct level and let the owner drive it for a number of miles. If the oil level dropped by more than a specified amount a new 3/4 engine was fitted. 

From this and other forums it appears that skimming the head is not possible as there is not enough valve clearance. 

[Ogster]

Understood and thanks. If it were just rings, why not simply replace them, and if just pistons then surely similar?

 However, I can see that if oil is passing even with new rings and pistons then there could be an issue with the liners/bore not being wholly concentric. The cheaper option could well be simply to replace the engine.