Cam belt failure

[will_]

A friend of mine has recently bought a 2002 1.8T Superb with 50,000 miles on the clock. Within 2 weeks of buying it, the cam belt has failed. It's back at the garage, who are fixing the damage, but I understand they're also muttering that the belt (and water pump) were only replaced 400 miles ago, that some other pulley has failed, and it must be down to his driving.

1. Please confirm my advice that any suggestion of a cam belt failure due to driving style is absurd!

2. What other pulleys sit on that belt? I thought it was just the water pump and a tensioner. In that case, surely the tensioner should have been replaced at the same time as the belt.

Thanks in advance.

[Danny 57]

1. Yes absurd.

2. Yes it (tensioner) should also have been replaced.

[KenONeill]

1. Yes absurd.

2. Yes it (tensioner) should also have been replaced.

Seconded.

The last time I saw (or heard of) a cam belt failing that soon after changing it was due to the belt being damaged by the fitter.

[mr rooney]

My new cam belt failed after 3k miles. It didn't snap but 6" of its teeth were stripped off causing the timing to be out by 3 teeth .

This was caused by the cam dragging on worn followers @103k miles.

[SkydiveMacca]

Hello all,

I'm the friend in question

To add a bit more information:

The engine failure occurred on the 14th day after pick it up

487 miles had been driven after picking it up

On purchase, the car was supposedly fully serviced as well as the cambelt being changed

I suspect the car is suffering from the water ingress problem as none of the electrics function correctly

Just before the engine failed, the engine started to get a loud rattle noise. I pulled over and it seemed that the rattle was only between 1500 and 2k. It sounded like the tappets. I decided to turn around and drive home, but shortly after doing this, the car stalled. I started it again to get me round the roundabout I was on, then as I cam off, the engine died completely.

The MFD has been intermittent, but it came to life shortly before the engine death and flashed up an oil pressure issue, but my money would be on this being another electrical issue?

I got the RAC to recover me to the garage I purchased the car from who said they needed a couple of days to look at it. RAC identified no compression from the engine.

I spoke to the garage this afternoon and asked for my money back - as assumed that it would not be economical to fix (I paid 2,200 for the car). I was rapidly put over to I guess a manager who was very blunt and rude.

He told me that they were fixing the car, which I was surprised at. I mentioned the SOGA to which he claimed he knew all about and that I had not bought their warranty, so it was just being fixed out of courtesy!

Apparently, they've stripped the engine down and sent the head to be skimmed. They will rebuild it and I can collect some time next week.

He said that the timing belt had skipped a couple of teeth due to a pulley and that was what caused the damage.

I said that they had changed the belt, so surely it had been done wrong.

He said that they changed the belt, pulleys and water pump. It was another pulley that caused the damage to the belt?? Now, I've got a fair bit of mechanical knowledge, not loads, but more that the average. This makes no sense to me. What other pulley or belt on the 1.8t can cause a timing belt to skip?

I asked this and he remained convinced. I said, either way, it was their issue - to which he suggested it was the way I had driven the car that caused the failure?! Surely there is NO way that that could be true?

Not a great start to Skoda ownership :(

[rwbaldwin]

It is possible that the aux belt snapped and got snagged in the cambelt causing it to snap. Whatever the cause, it isn't due to driving style and it isn't your fault.

[Gaz]

1. Yes absurd.

2. Yes it (tensioner) should also have been replaced.

Thirded. Does the 1.8T have one of the dreaded idler pulleys that isn't part of the cambelt kit?

If you're within the 21 days statutory right to reject goods, I'd consider doing so. Discuss with your local Trading Standards if not sure. Of course the seller's going to say they know all about the SoGA - treat that with a healthy pinch of salt. Link to my LA's pages:

http://www.eastsussex.gov.uk/business/tradingstandards/consumeradvice/cars.aspx

Hope you get it sorted.

Gaz

[will_]

Does the 1.8T have one of the dreaded idler pulleys that isn't part of the cambelt kit?

Yes, I think it does.

Edited 29 May, 2013 by will_

[BJM]

Standard VAG kit for the 1.8T engine comprises:

Belt

Tensioner

Idler Pulley

Bolts (2 from memory)

Other, non VAG oem kits may contain other, fewer bits, and it is possible to buy just the belt on its own.

TBH I think that in view of the problem with the engine and the possibility of the dreaded water ingress problem I'd be seriously thinking about talking to Trading Standards and demanding my money back under the SOGA.

[SkydiveMacca]

Update, and advice required

The garage have contacted me, and despite saying it was the cambelt and the head had been sent away, are now saying that it was the oil pump that had failed. They claim I must have been driving around with the oil pressure warning light on.

I think not.

The MFD had been temperamental at best and sprung in to life moments before the engine died and did display a warning about oil pressure.

My questions:

Are there two oil pressure warning lights: IE, the big warning that appears on the MFD, and another light not related to the MFD?

Could a badly fitted cam belt somehow cause the oil pump to not function correctly and ultimately fail?

The garage have given me two options - 1) fix it, but will take 6 weeks - 2) Refund, minus a contribution to repairs, which would be £300.

I'm not happy with either option and would like a full refund. I have asked for these options in writing so that I can seek further legal advice, but surprise, surprise, no letter yet.

I want to write to them tomorrow, so any advice on the above tonight would be really, really appreciated.

Thank you in advance

Macca

[will_]

I don't have any links to hand at the moment, but I understand this engine (I have one in my Octavia, and it's also used in countless Audis, VWs and SEATs) is somewhat prone to blockage of the oil pickup tube, which is shielded by a wire gauze that gets covered in sludge accumulating in the sump. From what I've heard, some people suffer with it while others have no sludge whatsoever. Do a search for 1.8t oil pickup pipe and you'll see plenty of material. Although it's not a regular service item, some people like to change them regularly.

May or may not be relevant to any further discussions you have.

[will_]

Also, if your oil pump has failed, beware of damage to the turbo.

[SkydiveMacca]

Thanks Will. I have seen many posts relating to this very issue.

What I'm trying to understand is if the failed cam belt could subsequently cause the oil pump to fail. I find it more than a little odd that they told me the cambelt was at fault (their fault), but they're now telling me it was the oil pump (trying to blame me).

If the shoddy cambelt fitting could cause the oil pump to fail, I have a very strong case for a refund.

After speaking to the citizens advice before this new information, they said for me to get a full refund, I would have to prove that the fault was there when I bought the car. If I just wanted a repair or replacement, the dealer would have to prove the fault wasn't there.

Unfortunately, as the car was recovered directly to the dealer and they've now stripped the engine, there's no way for me to be able to independently test the engine to establish the fault :(

[SkydiveMacca]

Vice versus as well - if the oil pump failed, could it cause the cam belt to slip?

They claimed to have sent the head away and ordered new valves, which makes me think it's more than a seized engine?

[will_]

Vice versus as well - if the oil pump failed, could it cause the cam belt to slip?

I'm slipping off the edge of my understanding here, but I think a seized engine (caused by an oil pump failure) could cause a cam belt to snap or slip, couldn't it? If the bottom end suddenly seized, I would imagine the momentum of the top end would place a bigger-than-usual stress on the cam belt. I'm not at all sure about this, though.

Edited 6 June, 2013 by will_

[rwbaldwin]

In theory, if the head is starved of oil, the camshaft can seize and that would snap the belt.

If the oil pump failed or the oil pump suction tube was blocked the damage would not be limited to the head. You would have heard knocking at the bottom end.

If the above was the case, then the faulty oil pressure light is just another reason to seek a full refund.

It's still not your fault. Do I think the above happened? - No!

[SkydiveMacca]

I certainly didn't hear any knocking from the bottom end, just the rattle of the tappets.

If the belt had failed, could it in turn cause failure of the oil pump?

Just trying to get my ducks in a row before writing to them again. Thank you all for your help.

[CRC]

If the belt fails ( ie breaks ) then the momentum of the crankshaft causes the pistons to carry on moving and hit any open valves causing immediate engine stop. The failure would be instant and immediate and no way could the engine be started again.

I've heard of cam belts "apparently" jumping teeth due to (say) red-lining in second and then finding first rather than third, causing dramatic over revving of the engine, but find it a little hard to believe.

When an oil pump fails, the supply of oil to the bearings of the crankshaft, camshafts and turbos will stop. Failure will not be immediate as there is still oil within those bearings and still oil on the bores. However oil from the crankshaft is being rapidly expelled from the crankshaft bearings due to the rotational speed of the crankshaft, and it's also leaking from the camshaft bearings and being scraped off the walls of the bores, so failure is going to come pretty quickly.

If still driven, then something is going to give and it's possible that the camshafts could start to seize in their bearings before the crankshaft big ends start to sound like Thor's hammer. If the camshafts start to seize then it will put intolerable strains on the cam belt and it will either strip teeth, jump teeth or break the belt.

Unfortunately, it might well be loss of oil pressure that caused the apparent belt problems.

I can't see how it can work the other way round, as the oil pump will carry on pumping as long as the engine is running. Not sure where the oil pump gets its drive from, but if it was from the belt, then jumped teeth would not affect it and a broken belt would stop the engine a long time before the loss of oil pressure could be an issue.

[CRC]

Regarding the oil warning system, I've just checked my owners manual and it says:

There is a warning light with an oil can symbol shown on it. It's position is second row down and far left on the information display.

It will light up red (low oil pressure) when ignition switched on (but only on cars without an information display.)

It says that (on all cars) the light will flash red while driving if there is low oil pressure and that 3 peeps will sound as an additional warning.

If it lights up yellow, then the oil level is too low and a peep will also sound. If it flashes yellow then there's a problem with the oil level sensor ( not the oil pressure sensor).

I've just checked on my car, and nothing lights up there when I turn on the ignition ..... but haven't started it to see what happens then. MIne has an information display so that would be right. Presumably the only time you would know it was there is when there is a problem?

Edited 7 June, 2013 by CRC

[rwbaldwin]

A problem with the belt will not affect the oil pump.

If the belt skips teeth, then the tensioner is at fault. The tension on the belt is equivalent to hanging a 55kg weight from it.

A seized lower engine (crankshaft) doesn't cause the belt to snap. If you stall an engine, it is pretty much the same thing - the crankshaft stops. Does it snap the cam belt everytime you stall the engine - fortunately not.

As I said in my previous post, the camshaft can seize due to oil starvation, but in the few cases I see, it is due to a long term problems.

The most likely causes of your problem are a blocked oil suction pipe causing long term reduced oil pressure (but not so low as the light comes on) or a faulty cambelt kit part or incorrect fitting of the cambelt kit.

It's impossible to rule out a one-of-a-kind failure in the same way I can't rule out the possiblity of Wayne Rooney forming a political party and storming to victory at the next general election.

It's still not your fault.