[Diy_efi] blown engine...

[Ian Molton]

Or so I thought...

some advice would be appreciated.

The turbo on my 18 year old Charade (1 litre 3 pot diesel) blew on the 
motorway the other day. I was driving along and started seeing a lot of 
blue smoke. Pulled to the side and popped the clutch on the way over 
(big mistake, but when you only have seconds to think you dont make the 
wisest choices...).

The engine __raced__ and I was rewarded with a huge cloud of black 
smoke. by now I'd turned off the ignition but it just carried on running 
hard. Eventually it slowed and stopped, followed by loud groaning / 
sucking noises.

Fearing the worst, I got it towed home and ripped the head off yesterday

amazingly, the bores are smooth (if full of oil), the engine rotates 
freely by hand, and the head appears not to be cracked. the head gasket 
must have gone (oil in water, water on the road) but damned if I can see 
where. theres a tiny chip out of one of the combustion chamber lips, and 
  pot no.3 has some small metal fragments in it (1 and 2 do too, but 
mostly 3.

The turbo binds badly and Im sure it was the cause of all this.

The questions are:

1) Why did the engine stop if its not seized?
2) I have another turbo. are there any special things I should take into 
cosideration when fitting it (like not using exhaust sealant prior to 
the turbine) ?
3) Is it possible that putting a 'T' in the turbo oil feed to run an 
[electronic] oil pressure sensor has killed the turbo somehow? it hasnt 
got a long tail on it or anything - its an aluminium block with holes 
bored in it and the sensor screws straight into the block.
4) does it matter what the oil feed pipe is made of? (I used copper 
brake line)