Cylinder Bore Scoring

[rhyseyness]

Evening all,

Long time reader/lurker first time poster.
I recently had my cambelt snap on my mk5 gti while I was driving. Started the teardown process to see how bad the damage was.
I've just got the head off today, and obviously almost all the valves are bent (as expected), but more worryingly, there is some significant scoring on the clyinder bores.
This is the first time I've had the head off since owning the car, so no idea whether this damage was caused by the valves hitting the pistons, of if it was there before this... event.

I'd like to know what people think in terms of the severity and whether there's anything I can do. I know it's hard to tell just from photos.
I suspect I need a new block, but would be very happy to be told otherwise!
Thanks in advance









Note: I had the cambelt changed 15k miles (2 years) ago by a garage, but I'm not convinced they fitted the correct belt from the state it was in when it came out.

[coolhandluke]

The right belt should be good for at least 4 years. Keep it as evidence and go back and challenge them.

[LC5F]

Cam belt should definitely last longer.
I am sorry to say the scores in the bores don't look good - if you can catch a finger nail in the scratch it is too deep.

With them being bright steel, they look fresh - if they were old I would expect some debris in the scores. actually, looking at the No.1 the score continues under the tide mark at the top of the bore, so it looks like its been there a while.
I experienced a belt fail - the valves just hit the pistons, nothing falls off unless you dropped a valve.

[rhyseyness]

The right belt should be good for at least 4 years. Keep it as evidence and go back and challenge them.

Do you think even though it's been 2 years since they fitted the belt there'd be any recourse?
I agree the belt should last much longer, but I don't have any evidence that I wasn't just very unlucky and got a defective belt by no fault of theirs.
I don't really see any benefit in going back to them to say "when you fitted this belt 2 years ago, it might have been the wrong one because it's failed early in its life."
Short of "ok thanks for letting us know" I don't know what they'd be able to do. Highly doubt I'd get any money out of them with my distinct lack of evidence outside of a receipt and a snapped unmarked belt!

Cam belt should definitely last longer.
I am sorry to say the scores in the bores don't look good - if you can catch a finger nail in the scratch it is too deep.

With them being bright steel, they look fresh - if they were old I would expect some debris in the scores. actually, looking at the No.1 the score continues under the tide mark at the top of the bore, so it looks like its been there a while.
I experienced a belt fail - the valves just hit the pistons, nothing falls off unless you dropped a valve.

Thanks for the reply!
The scores on 1 and 3 fail the fingernail test miserably unfortunately.
Appreciate you confirming what I already suspected would be the case!


Anyone know of a good shop to supply/fit a new engine for me?
Preferably around SE London with collection options!
I'm assuming that's more cost effective than having this engine re-bored, head repaired and rebuilt.

I've seen a few second hand options on Ebay, but I'm terrified of the condition of any engine I'm going to put in myself, as there wouldn't be a lot I could do if it didn't run, or died after 1000 miles!
Was happy to just have the head reconditioned and new valves fitted to mine, because I'd know the condition of everything at that point (obviously that's no longer an option with the condition of the cylinders).
Ideally would like a garage that can supply and fit a motor (ideally a quality reconditioned one) to give me some peace of mind/warranty!

Any thoughts/input appreciated. Especially if there's a completely different option I haven't considered!

[bobby_fodge]

Could break your car to get some money back and get another car?

[Octoparrot]

Could break your car to get some money back and get another car?

Unfortunately that's probably the most economic / sensible / likely outcome unless the car is absolutely mint otherwise.

[rhyseyness]

The car is by no means absolutely mint, but I've been working towards getting it that way. One day it will be if I can get it through this!
The most financially sensible decision would definitely be to sell it in parts or otherwise, but I'd much rather keep the car.
It holds sentimental value!
I'd like to bring it back to full working order with effectively a "new" engine.
If I can do this, I wouldn't be selling the car for many many years, so I don't mind spending the money.
I've done a massive amount of work on the car already so don't want to start from 0 again, so to speak.

[bobby_fodge]

If you are looking at these two options,

Anyone know of a good shop to supply/fit a new engine for me?

I'm assuming that's more cost effective than having this engine re-bored, head repaired and rebuilt.

I'd start by getting some prices for an engine rebuild and also quotes to refit it. I'd look at engine builders to do the engine and a garage to just fit it. It may be slightly more hassle but you'll then get the choice of which builder sorts you engine and won't have to pay the profit a garage would charge extra to get the engine built for you.

A call to VW will get you the cost of a new block and valves and whatever else you need.

Once you have all those prices you'll be better placed to make a decision on which option to take.

[pudding]

Scratches like that normally happen from overheating.  The piston ring gaps close up and they have no where to go except up or down, which breaks the ring lands, or expand outwards, which scratches the bore.....or a combination of the two.  Pretty common on remapped engines (most folk don't realise they are driving around with broken pistons until it starts smoking badly) but it never happens on standard engine unless cooling issues occur and it over heats.

Sorry to see this btw, always a gutting experience seeing a paper weight of a block after lifting the head.  It isn't recoverable financially as you'll need oversized pistons and the machine work to suit, which is mega money.

I think chancing a second hand engine is the most cost effective way forward.  Rebuilds and/or new blocks from VW are easily around the £3K mark.

[rhyseyness]

Scratches like that normally happen from overheating.  The piston ring gaps close up and they have no where to go except up or down, which breaks the ring lands, or expand outwards, which scratches the bore.....or a combination of the two.  Pretty common on remapped engines (most folk don't realise they are driving around with broken pistons until it starts smoking badly) but it never happens on standard engine unless cooling issues occur and it over heats.

Sorry to see this btw, always a gutting experience seeing a paper weight of a block after lifting the head.  It isn't recoverable financially as you'll need oversized pistons and the machine work to suit, which is mega money.

I think chancing a second hand engine is the most cost effective way forward.  Rebuilds and/or new blocks from VW are easily around the £3K mark.

As far as I know car isn't and has never been mapped, but that is very interesting as I had an overheating issue previously due to dead radiator fans, so could well have been the cause!
Thanks for the info, very good to know.

I've had a ballpark quote from AKS for a full forged rebuild with rebore and they reckon about £5.5k.
As you say, mega money, and even if I did have that laying around, they're not taking bookings at the moment.
They've recommended a couple of other garages who I'll contact and see what they reckon.

I'm leaning towards a reconditioned engine from "volksmine" which looks like it'll be about £2.5k for the engine plus all the other bits (seals, fluids, cam follower etc.) bringing it up to just over 3k.
Obvious downside is that I'll have to do all the work myself.
Still not cheap, but that's near enough a brand new engine which seems worth it to me.
https://www.volksmine.co.uk/audi-a3tt-20-petrol-200-bhp-4-cylinder-bwa-re-con-engine-166-p.asp
Anyone with first hand experience of this company would be massively valuable!

Was probably the worst I've ever felt about my car when I saw the scoring after lifting the head.
It put my brand new clutch slipping immediately after I put it in last year to shame! (Since replaced with a Helix performance one)

[Octoparrot]

With the costs and hassle involved I'd seriously consider looking for another car.

[rhyseyness]

With the costs and hassle involved I'd seriously consider looking for another car.

I am considering it, but I don't know that I could pick up a car of the same... calibre/quality for the same price (as the engine).
Decent mk5 GTI's at similar mileage are going for £3-5k. Spending that to bring mine back to "like new" seems like a decent option.
I'd be worried if I buy one at that kind of price it'll probably need a cambelt, cam follower, oil change, plugs, PCV valve, etc. unless I get somewhat lucky. (Be worried about the cambelt even if it has been done after what's happened to mine!)

Granted, I could sell mine, which would offset some of that cost of the "new" car, but I don't know how I'd even sell it in the state it's in, and the effort of breaking it out into all it's parts seems a lot more hassle than it's worth too.
Who in their right mind would buy 150k mile old suspension components or bodywork for example? Lol.
The peace of mind that comes with a "brand new" engine with warranty and not having to deal with getting rid of a broken car in many ways sounds like less hassle.
I really don't know what to do, and I'm in a bit of rut with it to be honest. Cars are pain.

Both options seem horrible (as a cambelt failure is always going to be! ), I just don't know which is the less bad one, lol.

Will see what some other garages say and then have a difficult decision to make one way or the other.

[bobby_fodge]

https://www.vwt4forum.co.uk/threads/new-engine.1215386/

https://www.google.com/search?q=volksmine&rlz=1C1GCEB_enGB1015GB1015&oq=volksmine&aqs=chrome..69i57j69i60l2.1065j0j4&sourceid=chrome&ie=UTF-8#lrd=0x487a428f98936f2f:0x89d75d26dd448bd1,1,,,,

[rhyseyness]

https://www.vwt4forum.co.uk/threads/new-engine.1215386/

https://www.google.com/search?q=volksmine&rlz=1C1GCEB_enGB1015GB1015&oq=volksmine&aqs=chrome..69i57j69i60l2.1065j0j4&sourceid=chrome&ie=UTF-8#lrd=0x487a428f98936f2f:0x89d75d26dd448bd1,1,,,,

Thanks!
Reviews look decent apart from a couple.
Those couple do worry me a little bit.
Their feedback on ebay is very positive.
The other forum post I'm not too worried about as I won't be having their garage in Coventry putting the engine in, and there's no complaints about the quality of the engine itself, just the rushed work putting it in; I'll be doing it myself and won't be in a rush!

I've just had a quote from them for my job:
"Thankyou for your enquiry of the BWA TFSI Re-con Engine.

The total cost for the rebuild is £1795 which includes VAT and delivery
+ collection of the old unit.
The build will be completed with a NEW Cylinder Head priced at £1000

The total cost including vat will be £2795

We will be building you a unit from stock. The unit is built to a very
high standard with the uprated oil pump kit and it will have a full 12
months or 20,000 miles warranty.
The build includes a host of new parts including Head Gasket,Bearings
big end+Main,guides,stem seals,Piston rings,water pump,belt kit"

Seems a reasonable price.
Brand new head (as all the valves are trashed on mine) and a reconditioned bottom end.
12 month, 20k mile warranty.
Bloke seemed decent on the phone.

What do you guys reckon?

[john_o]

how was it running before the cambelt went? burning much oil? noisy ? down on power ?
grant you the bore scoring is far from ideal, but it didnt happen just at the point your cambelt let go afaik. 
an suboptimal option is to get a 2nd hand head and just bolt it all back together