Exhaust valve and spark plug broken up ouch! Large port questions

StaceyS3

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Well it all started with a missfire on cylinders 1 & 3 in which i done the usual (change coilpacks) with no luck

So next i thought i'd check the plugs which 2,3,4, seemed ok but cylinder 1 was in a sorry state

Plug1.jpg


Plugs.jpg


Starting to worry now and with plenty of helpful advice from phone calls to bill along the way compression test was the next thing on the list, which produced some worrying results cylinders 1 & 3 had 0 compresson and 2 had 25psi whilst 4 had 60psi at first was a bit sceptical as the car was drivable and these were very low so bought my own compression tester and produced the same results.

Plans to prep the car for the ring with westy and prawn have now been put aside to remove the head and the results weren't good

Cylinder1.jpg


Valves.jpg


But the amazing thing is that the bores look ok, got a mate round who builds engines for a living and he said that they look ok but bore 1 is slightly glazed couldn't get a photo of it really but this is how the pistons look

Smallerbores.jpg


My friend thinks that that head gasket was slightly letting by between cylinders 3 & 4 and one of the headbolts which was between these was slightly rusty/orange? And he said could see water marks in bore 3 and on the gasket?

Going to be taking the pistons and rods out today and think it is a convienient time to chuck some rods in. :eyebrows:

My friend will back round sunday with a bore gauge to check the wear in the bores so hopefully wont have to take the block out?

But all in all cylinder 1 is obvious whats happened but cant work out what caused the low comp on the others

Help and opinions on cause and large port options would be very appriciated?
 
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Forgot to add that had been running inlet temps between 40-60 degrees once warmed up and the map was only a base map until i would eventually recieve my bigger ah cooler which convieniently arrived monday (two days after the missifre started) dont know if this will be related in any way but thought it possibly could be?
 
That head is cracked by the looks... in the pic with the damaged valve there is what looks like a crack spanning the small gap between the exhaust valves... this is where they normally go... you may need to clean off the carbon a bit with some scotch bright to see for sure but looks like it could have got hot in its past...

Bad luck if that the case :(

<tuffty/>
 
Since posting have found cracks between the exhaust valves on 3 cylinders but have accepted that this one is now probably scrap?

Good excuse to now go large port think you will probably see my future head in the making knocking around bills at some point ;)
 
Cheers bill does it look like it was in ok state?

Am rather unhappy have since found that the exhaust manifold has got a few cracks in it am pretty much certain that they werent there when it was fitted earlier this year and had covered plenty of miles on Pats car so suspect like tuffy said things have got rather to hot under there?

Really not sure what to do now as i'm sure an mtm manifold is a fortune £££££? :crying:

Will post pics up in a bit
 
Cheers bill does it look like it was in ok state?

Am rather unhappy have since found that the exhaust manifold has got a few cracks in it am pretty much certain that they werent there when it was fitted earlier this year and had covered plenty of miles on Pats car so suspect like tuffy said things have got rather to hot under there?

Really not sure what to do now as i'm sure an mtm manifold is a fortune £££££? :crying:

Will post pics up in a bit

was this ever mapped for the MTM kit?

Head condition I will know more when I can see metal under the oil and smeg which covers it all.
I will get it stripped down and sit in my degrease tank for a day or so to eat away the smeg.
 
It had the map uploaded but he said no point playing with timing etc until got the ait's down as ecu would pull anyway so plan was get the new cooler on and get the map finalised but all went tits up 2 days before the new cooler arrived get the feeling should have gone down a different route and got it sorted rather than waiting for ah?
 
It had the map uploaded but he said no point playing with timing etc until got the ait's down as ecu would pull anyway so plan was get the new cooler on and get the map finalised but all went tits up 2 days before the new cooler arrived get the feeling should have gone down a different route and got it sorted rather than waiting for ah?
 
some head pics.. stripped out the cams off it and followers etc
Sat in dunk tank for the night to loosen the burnt on oil/smeg etc

Will see better tomorrow whats what when its looking brighter and newer

IMAG1009.jpg

IMAG1010.jpg

IMAG1011.jpg

IMAG1012.jpg
 
It had the map uploaded but he said no point playing with timing etc until got the ait's down as ecu would pull anyway so plan was get the new cooler on and get the map finalised but all went tits up 2 days before the new cooler arrived get the feeling should have gone down a different route and got it sorted rather than waiting for ah?

what map is on it?
what boost levels was it running, what injectors when with it etc, had it been on a dyno for setting up and checking etc?
 
It was running the map for that kit don't know exactly what it was?

Kim Collins after loading the map took it out and logged for best part of an hour and said it wasn't worth getting on the dyno until I got temps down?
 
Forgot to say was running 1.75 bar spike with 1.55 bar to redline which is what ibwas told to get it at with their map??
 
It is a bam engine 2002 so pretty sure it has this?

Sorry but was posting from a iphone earlier so not at it's best?

Crack1.jpg

Crack2.jpg

Crack3.jpg

Wastegate port looks like it's about to break away :crying:
 
No not at all very depressed lolHave you heard of any proven methods of repairing cast with that kind of stresses involved I certinally haven't?Ps thanks for the pics
 
cleaned up after wash tank submersion and scrubbing/pressure washing
stacey-clean-head-1.jpg

stacey-clean-head-2.jpg

stacey-clean-head-3.jpg

stacey-clean-head-4.jpg


Some slight damage on Cyl 1 which will clean up with skim and minor fettle by me
head-slight-damage.jpg


Some interesting (to a 1.8t geek like me) differences in head castings between some heads
AEB Head of Stacey (off a passat)
aeb-stacey.jpg


AEB Head of Barks
aeb-barks.jpg


AQX smallport 1.8t-sport A3 head
aqx.jpg
 
hmmm, yea but..
I would need to compare overall lengths and groove positions relative to valve tips to confirm.
 
Unlucky on this one bud. I know how much you wanted to come to the Ring. I doubt your car will be ready now but maybe you can tag along in a mates car or something.

This type of engine damage is my worse nightmare especially with the milage I have on mine.

Great work as always Bill :icon_thumright:
 
Unlucky on this one bud. I know how much you wanted to come to the Ring. I doubt your car will be ready now but maybe you can tag along in a mates car or something.

This type of engine damage is my worse nightmare especially with the milage I have on mine.

Great work as always Bill :icon_thumright:

Cheers mate gonna give it my best shot, pretty much everything is in motion now, it is do able but realisticly probably wont be ready as am also away for two other weekends between now and ring :beerchug:

Going to be going in my mates tt if mines not ready as his only needs a couple of bits and bobs to get it road worthy

Cheers again Bill :superman:
 
Right have had good news from CR's they have inspected the turbo and theres no damage (PHEW) ;)

So that will be back with me tommorrow

And as for the manifold got a quote from Welding Process from Slinden Services, Lloyds approved, Pressure testing for £220 + vat but they guarentee their work for 12 months

Or after speaking to Kim and finding out he had two manifolds knocking about (which to be honest don't think they will sell anymore turbo conversions that cost more than the cars worth) he was happy to do me an ok price of £450 cash

So as much of a headache it is i thought ti was a bit of a no brainer as had enough of taking this turbo etc off in a carpark (don't fancy a forth go)!
 
we will have to review the valves/valve gear

There is a difference in groove length from valve tip to lower edge of top groove..
what I believe to be smallport valve is 4.6mm and the AEB ones removed from the head are 6.2mm
 
I was told that to get the vvt working correctly on a aeb head you have to drill a hole through the side of the head, is this true?
 
not aware of this.. The oil feeds are the same on vvt and non vvt, and all of them have hydraulic tensioners.

will have a closer look for differences tho.