Turbo Dead......?

[The enchanted broomstick]

Hi there, as some of you may know i own a peugeot 406 sri turbo.

Recently had the piston rings and head re-conditioned, new valves, tappetts, seats re-ground, new gasket, skimmed pretty much everything due to blue smoke on idle. After getting the car back i still had blue smoke on idle revs and the only thing that hadnt been replaced or repaired was pretty much the turbo.

Over the last week or so when the turbo is about to cut in i've been getting little cuts - kind of mini losses of power then it would clear and be alright again, i thought it might be the plugs or leads so they got changed to no avail.

I spanked it a little while ago and it hit a huge amount of cut, i lifted off the accelerator put down again and repeated with just no power left. The engine sounds like its firing on all 4 cylinders properly and the boost is showing positive on my turbo gauge with the dump valve still giving off some noise. The engine isnt running quite as it should be on idle or anywhere throughout the rev range.

I do have oil round the turbo pipes and i can see a big spray has come out of the dump valve as its covered my engine bay.

I'd like to know what you guys think....? (besides the buy a new car theory)

[JTM]

Something sounds majorly bad if your getting oil spray from your dump valve..... check your oil level. Sounds like one of the seals have gone int he turbo or the likes so oil from the turbos bearing feed is somehow getting into the air flow and is being flung out the dump valve when you lift off. Problem is, when your not lifting off, its going into your inlet?!

[The enchanted broomstick]

Im thinking it would be a lot more than the seals the car is now permanently stuck in a state of lost power. Whatever happened when i spanked it something gave way. Im starting to think i've shattered the turbo....?

[Fish-Finger-er]

thinking either an oil seals gone, or the oilways been blocked and the pressure has forced one of the seals to leak..

then got 2 theories on what happens after this, either the turbos been starved off oil and ran dry, and the turbos failed due to this.

or a big glob(technical term there, way above most peoples heads). has entered the turbo at once, either from the seal giving way totally, or just from it releasing the built up pressure. and its tried travelling through the turbo itself, now as you may(nay should know) a turbo basically forces air into the inlet manifold, so it becomes pressurised(higher than atmospheric pressure, more air in the same space than you would get in the outside environment) basically compressed air.

now as you may remember from physics in school, you cant compress a liquid, therefore can see there being major problems when it gets chucked through the turbo and it tries to compress it, could easily cause a blade/vein to sheer off or cause enough resistance between the 2 impellers to break the shaft.

this theory of oil causing the boom also explains why it was smoking previously, and why your dump valves spitting out oil

however, im willing to say, that chances are, if you can build a bike, you can take a turbo apart to inspect it,and then reassemble it again. there all pretty much built the same, and the hardest bit will be accessing it on the car.

so hoses off on inlet side, and exhaust side.(jubilee clips or the stupid clampy clip thingies) turbo off exhaust manifold (13/15mm bolts). oil feed off(most likely 2 10mm bolts). then haul the turbo out. u can then see pats of it through each end. try and spin it, see if it spins freely and if anything feels lose/rattles and that the shaft connects the 2 impellers. should then be able to take off the 5 or 6 bolts clamping the 2 bits of the surround round the impeller. may have to take off the 2 end nuts. should then be able to open it, and see if the veins are in good condition/still exist. if they do, suggest you take it to an engineering place, ask them there opinion on it, else it looks shagged, take it to an engineering place, ask them what they can do(take it your not much of a mechanical man, so overhauling it yourself is outta the question, as is finding a donor one from the scrappy)

mechaniccings all nuts and bolts once you get your head round the fact you dont know exactly what every bit does and how it works, you just need to remember the order stuff came off in, where it came from, and have a rough idea of what should be where, and double check every bolt

[Smo™]

Might try checking the coil pack too, just in case.

[The enchanted broomstick]

thinking either an oil seals gone, or the oilways been blocked and the pressure has forced one of the seals to leak..

then got 2 theories on what happens after this, either the turbos been starved off oil and ran dry, and the turbos failed due to this.

or a big glob(technical term there, way above most peoples heads). has entered the turbo at once, either from the seal giving way totally, or just from it releasing the built up pressure. and its tried travelling through the turbo itself, now as you may(nay should know) a turbo basically forces air into the inlet manifold, so it becomes pressurised(higher than atmospheric pressure, more air in the same space than you would get in the outside environment) basically compressed air.

now as you may remember from physics in school, you cant compress a liquid, therefore can see there being major problems when it gets chucked through the turbo and it tries to compress it, could easily cause a blade/vein to sheer off or cause enough resistance between the 2 impellers to break the shaft.

this theory of oil causing the boom also explains why it was smoking previously, and why your dump valves spitting out oil

however, im willing to say, that chances are, if you can build a bike, you can take a turbo apart to inspect it,and then reassemble it again. there all pretty much built the same, and the hardest bit will be accessing it on the car.

so hoses off on inlet side, and exhaust side.(jubilee clips or the stupid clampy clip thingies) turbo off exhaust manifold (13/15mm bolts). oil feed off(most likely 2 10mm bolts). then haul the turbo out. u can then see pats of it through each end. try and spin it, see if it spins freely and if anything feels lose/rattles and that the shaft connects the 2 impellers. should then be able to take off the 5 or 6 bolts clamping the 2 bits of the surround round the impeller. may have to take off the 2 end nuts. should then be able to open it, and see if the veins are in good condition/still exist. if they do, suggest you take it to an engineering place, ask them there opinion on it, else it looks shagged, take it to an engineering place, ask them what they can do(take it your not much of a mechanical man, so overhauling it yourself is outta the question, as is finding a donor one from the scrappy)

mechaniccings all nuts and bolts once you get your head round the fact you dont know exactly what every bit does and how it works, you just need to remember the order stuff came off in, where it came from, and have a rough idea of what should be where, and double check every bolt

Now that does sound quite passable. My cousins coming over tomorrow (he's worked with performance cars all his life) so we are gonna inspect the turbo - i had the turbo checked friday just gone and they told me there is latteral play in the shaft - maybe this has caused the turbine to wobble so much when its at 70,000+ rpm to snap the shaft and completely disintigrate the insides of the turbo...? When the turbo was checked on friday they only had to remove one pipe to have access to the shaft so im thinking if we do the same tomorrow evening then i may well come across a destroyed turbine.

I hope it is the turbo to be honest because the garage that charged me for piston rings etc and a head re-condition told me that the turbo was not the cause of the problem. If the turbo is now dead they will be held liable for incorrectly diagnosing the cause for blue smoke on my car and thus will have to sort out my turbo problem free of charge.

What a bugger though - just spend £1880 on getting my car sorted out then one month later it has gone and died on me AGAIN! i dont know how much more of this i can take!

[dave85]

I dunno what the sealing arrangements in a turbo are like, but excessive play in the shaft in any direction will screw up the best seals in the world. If blades were missing off the compressor or turbine, it'd be badly out of balance and vibrate like a b*****d, not to mention it probably wouldve thrown the blade through the side of the turbo. My money is on a buggered turbo, so get your reciepts together and get ready for a good barney with the garage