Thread: TD5 Turbo dying ?

Crossy999,

Can you feel the blades touching the wall of the housing when you force them to the side and rotate them?(NOT using anything other than your fingers...)

sideways play is normal for plain bearing turbos, even though it sounds abnormal, the turbine and shaft assembly is finitely balanced to rotate at speeds over 100,000rpm, so unless the bearing surfaces are really worn, then it is difficult for the blades to actually touch. Can you see the edge of the blades? They can also look slightly burred if they have been contacting the housing. The housing is bored at that point smoothly also to reduce turbulence and noise. Is the turbo noisy during boost, more than a whistle?

If you could measure the deflection with a dial indicator I could provide more help, I have seen enough of these to determine at a glance what is excessive and what isn't, but diagnosing from here is difficult.

On the issue of if it is worn, then there are several reasons for it. Contaminated/ diluted engine oil. I have seen Td5's with long term sump dilution due to diesel leaks in the head destroy turbo bearings because of poor lubrication. The manner in which the vehicle is driven and then shut down, the quality and frequency of oil changes, all these play a part in its lifespan.

JC

you will also want to check the back and forth play of the mounting spindle.

Imho thats the more important check if the blades dont contact the mating surface.

are you getting any oil coming past the breather into the inlet side of the compressor, the effort of the turbo flinging that can polish the housing quite nicely.

your most likely to get gouging of the housing directly opposite the outlet side of the compressor or the opposite the turbine inlet.

There is a lot of movement in the TD5's turbo shaft due to the shaft floating in oil - a new design at the time. I went through this some years ago whilst trying to determine the cause of bad hesitation, and compared my turbo with those on new TD5s. The turbo also stops very quickly too due to not having any oil to float on with the engine stopped and drags on the seals, another indication of the lack of tight bearings.