It went "poof" - Happy Xmas Ian!

[IanH755]

I put this in the "Readers Car" section too but just incase people don't see it in there -
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F**********************************************************************************CK!

As a "Happy Christmas" present my car has decided to do something catastrophic, involving the No1 Cylinder and a whole bunch of burnt oil! I'm in the process of stripping the intakes down and pulling the No1 plug out when my shitty luck continued.

Not only does my spark plug tool not fit, not only has the locking part of the coil-pack plug dropped somewhere into the engine bay (supposed to stay attached) but I've also somehow managed to drop a little spring from my pliers down the intake pipe past my blue-roll "blocker" (1 squillion to one shot!) and it's now sitting nicely infront of the turbo blades (hence the boroscope shot of the turbo), which should be fun getting out if it's not magnetic!

Once I get to Halfords for a new spark plug tool on boxing day I'll eventually take the plug out and boroscope the cylinder to see whats happening and see why the plug isn't firing properly. I did notice the Crankcase Vent pipe line from the oil separator to the turbo's is dripping with fresh oil when it should only have vapour residue, not good!

Anyway Happy Christmas Everyone

[Surrey Sam]

Bugger...not a nice time of year to be twirling the spanners as well Ian.

Hope it works out alright, what are you thinking as the likely culprit, a Piston/Piston Ring?

[IanH755]

I'm thinking worst case so piston holed with a damaged bore, until I can get the plug out and inspect it to be sure.

Whats odd is that I was only doing 80-ish at around 3000rpm (simple m/way overtake) with 1/4 throttle and, as it went to over-run, there was a "whump" and a cloud of blue/white smoke so if it is the piston it's gone under "normal" conditions rather than at high rpm under full boost, which is where I'd expect it to go.

However it is a 108k mile engine running high power so things like this are to be expected. At least if it is a dead engine the mileage doesn't count any more as it's already got new everything else (suspension/GB/diffs/propshaft etc) so after a new engine it's only the body left thats done the original mileage! Silver linings and all that

[Jim Haseltine]

Could be as simple as a failed plug, but looking at the worse case can make you feel better whan you find the cause.

December is usually my month for the shitty end of the automotive stick. Over the years I've had it many times that I've lost count.
Clutch, radiator, even had a car 'entered' one night (my fault for not noticing that it didn't lock properly), lost some small change and minor bits and bobs - they obviously didn't think much of my taste in music because they left my CDs and they never thought to open the glove box and find my sat nav. They left me a used syringe and needle in exchange though.
Few years back I did two cars in one day - on Christmas Eve. Siezed a brake caliper on the way to work (nice 360 degree spin and managed to miss every thing else on the road. Limped it home, took my daughter's car to work. Wouldn't start at the end of the day - cam belt tensioner had shat its bearings.
Year after that I lost the alternator on the way to work beyond the halfway point so kept going. Battery gave up half a mile from the car park.
As you can probably imagine, by that time I was starting to think there was someting in that there religious lark.
Ever tried to get recovered on Christmas Eve?
No?
Me, I'm an expert.

As to recovering the spring I find that well-worked Blu-Tac (as in really sticky) can often be your friend.

[IanH755]

It's the oil in the cylinder that's got me worried, can't be a blown plug doing that unless something has failed and scored the bore. It could also just be a simple valve stem seal but I won't know for a bit.

Blu-tac - Given it's position I don't want to push the spring into the turbo so a grabber/magnet on a stick (Halfords sell a twin pack) is my safest bet but worst case I'll whip off the intake pipe and get some very sticky tape on a stick or even my fingers depending on the pipe length (oo-er)

[FaisalJ]

Mate - that is properly sh*tty!

Hope you get it sorted.

Actually scrap that.

You WILL get it sorted. Just a matter of time, and hopefully not too much money.

This'll cheer you up.

https://youtu.be/G9PyW259YWY

[Covkiller]

Oh fuckerty bastard bollocks !
That really is bad <beep>.
I hope you get it sorted, these cars are getting old but worth keeping in good fettle.

[A20LEE]

Hope you have a great christmas regardless!

[IanH755]

So got the spring out yesterday



and got my 16mm spark plug socket today and whipped the plug out (extremely surprised to see an OEM plug too!). It looks OK with no damage, it's just coated in oil stopping it firing -







And the boroscope, despite being producing an absolutely awful pic, doesn't show any obvious signs of damage, just more oil burning, so the oil doesn't look to be coming past the rings so it must be coming coming down through the heads which makes me think Valve Stem Oil Seal but the boroscope pics aren't clear enough to be absolutely sure -

[Quattro_RS6]

For me it looks like you have a blown piston there mate. It's not easy to see from the pictures alone, but on picture no.1 it looks like you have a small "dent" into the piston, and a small gap between the piston and the cylinder? This is the kind of piston damage you normally would see if you get too lean fuel mixture resulting in engine knock/detonation.

Hope i'm wrong!

[IanH755]

So I took the plugs out of the other 3 easily accessible cylinders and checked both the plugs and the bores.



The plugs all looked fine (all the same as this)



I did a quick boroscope of the 3 cylinders and found a "little" amount of shallow scoring on all but nowhere near as much as on the No 1 Cylinder and I also found that all the pistons had that same "missing" section in the piston crown so thats the design of the piston and not an issue in the No1. Here's a few random pics of the other cylinders showing the same "missing bit in the No2 an No4 and showing some of the bore marks and the No 2-3-4 cylinders.











So I cleaned up fouled plug, rebuilt the engine putting the No1 cylinder plug/coilpack into cylinder 3 to see if they were fine and put the working No3 plug/coil into cylinder 1. Started the engine and there is still a misfire on Cylinder 1 (No3 runs fine so plug/coil OK) and, now I've got bore pics from 4 cylinders to compare, it's pretty obvious that the No1 has 1 if not 2 deep scores about 180' apart so I'm fairly sure it's lost compression

It gets taken up to Unit20 next week so I'll let Grizz take it apart and see how bad the damage is, cry a little and then prepare my anus for the bank manager/Audi!

[Jim Haseltine]

IME, stem seals don't pass much oil when the engine is running - they usually leak when the car is standing and burn it at start up. And that's a lot more oil than I've seen from a stem seal, even on a knackered Ford Pinto that threw a smoke screen that James Bond would have been proud of. I'd try a dry/wet compression test, could be just the oil control ring.
Mind you, 'just' is a little word that covers a lot of pain.

[Farravi]

Oh my, that's not good! Well, on the bright side, worst comes to worst, an engine replacement will possibly wind back the mileage on the giving you the pleasure for years to come

[Vieussuex*]

Eeek! Fingers crossed it hopefully all gets sorted!

[Bladerider]

Unlucky chap,

I think you've broken the land on No1
Hope you get it sorted easily enough, if you need or want the Alusil sorting then there is a company in the UK doing this.

J.