Thread: TD5 Turbo

Speaking from experience from having owned 3 petrol turbo cars I offer the following.
One reason cars have wastegates is to not send too much boost and cause detonation, the other is not to overspeed the turbo.

Any increase in boost is caused by What, do you think? Its the turbo going FASTER. The wastegate is to bleed off EXHAUST gas so that the turbo does not go faster than its design speed. If that were not the case they would bleed off INLET boost.

Going faster than design speed is BAD. the turbo gets much hotter , The bearings can run, or in some turbos the wheels can disintegrate.

So what I have been saying all along is that these chips that you TD5 guys buy are just speeding up the turbo to give more boost. You trade boost for life. There is no such thing as a free lunch, even though the promoters promise it.
Regards Philip A

my turbo still functions as normal it just squeals

not sure what the cause is, maybe dry or even dirt 8O

alan that other squeal you here is the fuel pump
but not any more all fixed [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img] [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img]
darn fuel filter was shagged

interesting discussions, but getting back to my original question -

where do I find a workshop manual for the TD5 turbo?

sorry mate can't help you there

Squealing turbos are normally caused by oil carbonised in the bearing from hot shutdown. The bearings are usually damaged quite quickly by this. The fix is a turbo rebuild. You cannot really rebuild a Turbo yourself as the shaft and two impellers have to be dynamically balanced. that is why you see the bits ground off the nut. Dynamic Turbo et al do rebuilds
regards Philip A

Originally posted by PhilipA
Squealing turbos are normally caused by oil carbonised in the bearing from hot shutdown. The bearings are usually damaged quite quickly by this. The fix is a turbo rebuild. You cannot really rebuild a Turbo yourself as the shaft and two impellers have to be dynamically balanced. that is why you see the bits ground off the nut. Dynamic Turbo et al do rebuilds
regards Philip A

We were chatting about this at lunch yesterday... do you think a all synthetic with their higher heat tolerance would be better for this application?

<div class='quotetop'>QUOTE</div><div class='quotemain'>do you think a all synthetic with their higher heat tolerance would be better for this application?
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IMHO, most definately, (this is one of the reasons I use Delvac 1) although a qick idle down will suffice. The turbo on a Tdi (Garrett T250), and IIRC, a Td5 (Garrett) is oil cooled, wheras on, say, a WRX, or non-intercooled Patrol (Mitsubishi TD04 and TD05 turbos) they are also water cooled around the bearings, which obviously helps reduce the localised superheating of the oil in the bearings.
As Phillip says, the balance is critical, and it is usully a balance problem that causes excessive noise in small turbos, often by the ingestion of something (even excessive dust, eg a K&N air filter) causing the compressor wheel to be out of balance. Also those that do turbo mods (eg changing to different sized wheels) without re-balancing can cause this. This was from a DTS bloke I was having a chat to one day.

Septimus, you'll probably have to go to someone like DTS/MTQ for info as most car manufacturers only recommend replacing the complete turbo, and so don't issue any service information. In fact, It may be cheaper just to drop it off at your local DTS dealer and have them test it for you.

Originally posted by rick130

Septimus, you'll probably have to go to someone like DTS/MTQ for info as most car manufacturers only recommend replacing the complete turbo, and so don't issue any service information. In fact, It may be cheaper just to drop it off at your local DTS dealer and have them test it for you.

Thanks for that. I am starting to get a better understanding now of what it is about. Never having had a turbo before it was all a mystery to me.

One question though. Is the turbo drive adjustable in any way? I was wondering if there can be drive slippage or whatever that could impact on performance.