Thread: Another TDV6 Crankshaft Bearing Failure

Originally Posted by garrycol

How does poor fuel make the main bearing spin - I don't see how this is linked to the issue of crank failures.

Garry

Poor fuel destroys the engine oil quicker,has something to do with sulphur content of the fuel.

Service intervals are shorter in many countries with poor quality fuel.

Originally Posted by scarry

Poor fuel destroys the engine oil quicker,has something to do with sulphur content of the fuel.

Service intervals are shorter in many countries with poor quality fuel.

If there is enough fuel getting into the oil to destroy main bearings, then I would say the main problem would be how the fuel is getting into the oil in the first place, Regards Frank.

Originally Posted by scarry

Poor fuel destroys the engine oil quicker,has something to do with sulphur content of the fuel.

Service intervals are shorter in many countries with poor quality fuel.

Ok but I fail to see how fuel quality impacts on the oil.

Cheers

Garry

As you know diesels run and ignite fuel from the heat caused by compression. Diesel fuel contains sulfur.
Because of such high compression a certain amount of raw fuel escapes past the piston rings into the crankcase. This is known as piston ring blow-by. Sulfur turns special diesel motor oil black very quickly. All diesels do this.
New less powerful diesel fuels contain less sulfur than it did in the past.

It's extremely important to always use special diesel multi-viscosity motor oil. It has additives to hold fuel blow-by in suspension.

So it can be a case of poor quality diesel as well as the combination of cheaper engine oil and infrequent oil changes.

Lets no get side tracked with assumptions - there is no evidence that the 2.7 TDV6 crankshaft issues is caused by fuel issues. These is plenty of evidence that it is a "physical" issue related to bearing shells and their quality - whether it is systemic or just a batch quality control issue is not sure.

If anyone has evidence of a fuel related issue than post it up but lets not get distracted by assumptions or guessing.

Has your fuel consumption gone up? Smell your dipstick and see if it smells like diesel, or drain your oil and have a look. But if its under some sort of warranty then dont touch it.



I'd say its a bearing shell material problem.

Wouldn't gummy or higher viscosity oil cause more drag on the bearing shells and if gummy enough (due to infrequent oil changes) could cause the shell to move in its housing, blocking the oil hole?
Many oils marked diesel on the shelves are actually much higher viscosity (20-40) than that recommended for our modern LR diesels (5W-30).
Just a thought.
Barryp

When my old 98k 2.7 was removed from the D3 after top end issues caused by the mechanic, they decided to rebuild it so they could sell it.

I remember them telling me when they pulled it apart the front bearing caps were only just over finger tight and chances are they would have come loose within a short period of time.

From memory it is the front bearings that seem to be the ones that fail on 2.7's, but is it the bearing or the cap coming loose and the bearing then being destroyed? I would hazard a guess not to many engines get pulled apart and checked before they go bang like mine did.