why has my turbo failed? 1.8t

[Ste.Sales]

Two days ago i was traveling on m62 at 70mph. Put my foot down to overtake and got an awful whine.. And a slight lack of power. No smoke of any kind. Anyhow, i came to drive it this morning forgetting this had happened. It struggled to start and when it did it misfired badly and i got a huge puff of blue smoke. I have a spare turbo that i was going to fit to my zr, so i decided to remove my old one and replace. To my horror, the boost hose and intercooler were flooded with oil.. I drained half a litre from them!!! The turbo was completely shot, the compressor wheel had 4mm of play! And was worn badly, almost looks like the edges of the blades have been melted off.
My question is, as in the title, any ideas why it might have failed? I dont want a repeat failure with new turbo. Oil feed and return are not blocked and have excellent flow. Oil and filter changed 800 miles ago. No headgasket issues.
Thanks

[victorgte]

My 1.8T turbo failed at 99k. They do wear out eventually. Regular oil changes will prolong their life but not forever.

[Ste.Sales]

Nothing to panic over then? Car has only covered 56k miles.

[Avulon]

Could be it's been run short of oil in the past before you owned it. Could also be mileage related possibly, what is the mileage on it? (edit: not mileage related. Probably previous lack of maintenance and or mistreatment.)

One possible reason is infrequent oil changes coupled with thrashing it without a proper warm up and then turning it straight off while the turbo is still hot from a thrashing, giving insufficient time for the turbo to cool properly. Thrashiing it while cold will accelerate the bearing wear and failing to let it cool down on tickover for a few seconds will not help the seals. Of course it could just be that you're unlucky that it's failed, turbo's are by nature highly stressed in normal usage and failures aren't uncommon. Regular Oil changes and gentle treatment both when the oil is cold and also when the turbo (and oil) is hot can help to give the turbo an easier life.

Even on the diesel which has a fairly reliable turbo if I pull up after just taking it real easy for the last half mile, and then switch straight off I can still hear the turbo wind down, only now it's got no oil pressure. I always try and give it just 5 seconds ticking over before switching off - more if I've really been giving it some welly immediately before. Also try and drive gently until at least the coolant (temp gauge) comes up to normal. (I'm probably telling you what you already know, so ignore it if so).

[VVC-Geeza]

Some time ago, andy willi,one of the traders on here spoke of doing a "How to" on refurbing the 1.8 turbocharger.Sadly it never came to fruition, as I would be keen to do this with my spare.If anyone has the knowledge required please post up up the details.

[Ste.Sales]

Thanks for the info. It had full service history with a stamp every 8k miles ish. May well have been how it was driven previously, this didnt even cross my mind.

[louis71]

Thanks for the info. It had full service history with a stamp every 8k miles ish. May well have been how it was driven previously, this didnt even cross my mind.

To your knowledge has it had head gasket problems in the past? I've heard and also had experience of my turbo charger breaking down a few months *after* head gasket failure.
Not sure of the exact reason, someone with more expertise will possibly explain why, but head gasket failure in the past can have a detrimental affect on the turbo.

hth :}

[roverbarmy]

When turbos were first introduced, the golden rule was give it chance for the oil pressure to build before revving the engine too high, on initial start up. The turbo bearings can soon wear when the oil has drained back down into the sump overnight and the engine is caned on start up. The turbo spins at much higher revs than the engine speed so needs a good oil supply. Similarly, a turbo engine benefits from being allowed to tick over for a short while before switching off as the turbo can still be spinning at high revs if you just stop and switch off (ie turbo spinning with no oil pressure as engine is stopped). At least that was the theory many years ago (when I was a lad!)
It's something that I still do and I never had a turbo failure with trucks or cars that I have had over the years. ;)
Mike

[Ste.Sales]

In response to louis71, it had headgasket replaced 14 months before i bought the car, invoice with car service record. Dont know if it had failed or just replaced as precaution.
Is it easy to fit a turbo timer to these cars?

[dirtycdti]

Hi, I have been here twice with the turbo failing on two of the three zt I have had.

I do have a turbo from my old zt that was scrapped last month, I had my husband remove it off the car.

There is particularly 0 end float on the turbo, what would a woman know I bet your thinking lo, my husband is heavily involved in turbo charging of massive plant equipment,

Make me a offer, it comes with the manifold if you want it I don't want a lot as it's sat in my conservatory in a black plastic Bag.

[bl52krz]

In response to louis71, it had headgasket replaced 14 months before i bought the car, invoice with car service record. Dont know if it had failed or just replaced as precaution.
Is it easy to fit a turbo timer to these cars?
The probable reason then is that when the gasket went, water was mixed with the oil, and the oil/water system was not flushed, or not flushed out thoroughly .

[Doc Evil]

To your knowledge has it had head gasket problems in the past? I've heard and also had experience of my turbo charger breaking down a few months *after* head gasket failure.
Not sure of the exact reason, someone with more expertise will possibly explain why, but head gasket failure in the past can have a detrimental affect on the turbo.

hth :}

You've right when hgf occurs and oil mixes with water the lubricating properties of the oil are drastically reduced therefore the turbo is in effect running without oil and wearing rapidly(not strictly accurate and cooling stresses play a part as well, but suffice for the explanation) so the turbo tends to fail after hgf where mayonnaise is formed

Doc

[Sector-9]

What the hell was that VAG running on!? It looked like they'd removed the HT leads which would imply it wasn't a diesel engine. And although I've seen plenty of these 'runaway' clips, I've never actually seen one where they go boom - they just tend to rev away noisily.

Scarily, I had a runaway twice on my 45 whilst going down the M1: I was accelerating hard when all of a sudden there was a surge forward and lots of smoke out of the rear - letting off the throttle had no effect and I was gaining speed. Thankfully in fifth gear I could use the brakes to get the speed/revs down and it drove ok until I booted it again whereupon the same thing happened. I did the rest of the journey home at a low cruising speed and had no issues. Long story short, the intercooler had never been drained of oil and enough had gathered in there that with high air flows some was getting drawn in to the cylinders. At lower revs this didn't happen, whereas if the turbo bearings had gone it'd probably have ran away at much lower revs. Drained and flushed intercooler and it's been fine since.

[Ste.Sales]

Well i now have a shiney new one fitted and is running perfectly. 7 hours start to finish, most of my time was used cleaning out all the hoses, sump oil pickup and intercooler, oil feed and drain pipes. Also noticed i have a small hole in the plastic boost pipe. Temporary fix with rubber tape. Thanks for all advice. I will be sure to keep on top of oil maintanence.

[Ste.Sales]

Yeah, i got a new CHRA from turbocharger systems. Came in a box with turbotechnics plastered all over it. Comes with a 5 year guarantee (if u replace oil feed) and has a ton of technical specs including a graph of it running at 180000rpm for balancing purposes.
I had a spare used one which looks like its hardly seen any use, i got a new core (just to be sure) and used the compressor housing and turbine housing from my spare.
The CHRA cost £160 with next day delivery. I have no idea if this is good value or not... But seemed reasonable to me.

[DMGRS]

That seems like excellent value to me - I've seen the price of the 'chargers new, and you've come off lightly! :D

For anyone also doing this job, a lot of warranties stipulate the oil feed pipework must be changed with receipts to prove.
We've got the oil feed pipes here: Oil Feed Pipe - 1.8T (http://www.dmgrs.co.uk/collections/pipework/products/r75-mg-zt-1-8t-turbo-oil-feed-pipe-pnh000240)

They have been NLA for some time now - as far as I know, we're the only place with remaining stock.