Engine needs replacement after improper cambelt change

[geolee]

Hello,

 

I have a Skoda Octavia TDI and at 60000 miles I asked my mechanic to change the cambelt (as indicated in the manual). The car was in perfectly working order and never had any problems with it, so only had the camblet changed because the manual recommends this to be done at 60000 miles. In November 2010 the mechanic changed the camblet and the car worked fine until last week (so three months later) when it just stopped in traffic. I called the AA and their guy said the camblet jumped timing; the mechanic who changed the cambelt confirmed this today after failing to start the car.

 

He will come back on Monday and try to reposition the belt but there is a very high chance that the belt has already damaged the engine valves, which means that the engine (and therefore the car) is unusable. Given that the camblet was supposed to last at least another 60000 miles and it broke after only a few hundred I wander what are my rights and what can I ask the mechanic to do about this.

 

Many thanks for your help.

[Conniff]

An experienced mechanic will fit a cam belt and then tension it by twisting it. It will only twist so far depending on the force used. That same experience mechanic might get it right 9 time out of 10, or 99 times out of a hundred but this isn't the way to do it. That is fine for the trip to the dealers to get the tension set as per the manufacturers figures, but shouldn't be taken as tensioned correctly, only a temperary measure. All makes have different setups, as well as models within that make so an independent garage is unlikely to have a tensioner for your car, there are so many model specific tensioners that it's practically and certain financially impossible to have them all.

You're obviously the one out of the ten that he didn't get right, so I would say that it is down to him to put the car back into working order. He might be lucky and there is no damage, but he should be once bitten twice shy and then book it into the dealers and have the correct tension set on the belt.

[heliosuk]

Conniff is spot on here. What has probably happend is that he's been the unfortunate victim of what is known as torque relaxation when tightening the tensioner. This is caused by re using the fixings i.e the nuts and bolts.

 

The possibly good thing is that I believe this engine is what is known as a safe engine where if the belt moves or breaks the pistons do not hit the valves. This will explain to a greater extent why it would not start as it would be immeadiatly apparent if the pistons had hit the valves with knocking noises. The fact is he got it right in the first place so it's not necessarily so that he got it wrong and could put up a pretty good defence if you wanted to take it further. The car afterall did do a few hundred miles which suggests he did get it right initially.

 

It's a sad lesson for all here, that whilst all the latest servicing info is freely available for all makes due to EU regs, parts suppliers and people outside of the franchised outlets don't always keep upto date with the latest tech info despite it being available. Fixing torques can change all the time but all too often repairers overlook them.

 

Traditionally there was finger tight, tight and F tight, this is no longer the case, it has to be right and you just cannot use nuts and bolts twice as they are seldom designed to be so.

[MARTIN3030]

VAG cambelt kits are actually not a bad price using their TPS.

In fact they are very competitive compared to GSF and Europarts who are OEM suppliers.

The 1.9 Tdi engine is pop across many models.

 

Tommy -If you are still using Autodata 2006 you obv dont do much on late vehicles.

[j66]

It could be more basic than that. Was the water pump changed at the same time as the belt?, we always recommend a water pump change and always use a cam belt kit. We even lost a job when the customer thought it was not necessary and got just the belt changed elsewhere for a much lower price, he came back to tell us. We saw him again a few months later when his car was towed in with an expired water pump, that stripped the belt and bounced the valves off the pistons.

 

It's a diesel engine, compression ignition, which means that the compression ratios are quite high. The majority of lower compression ratio petrol engines are not 'safe', so I doubt that there are any 'safe' diesel engines.

[geolee]

Yes, the water pump was changed as part of the kit.

 

It could be more basic than that. Was the water pump changed at the same time as the belt?, we always recommend a water pump change and always use a cam belt kit. We even lost a job when the customer thought it was not necessary and got just the belt changed elsewhere for a much lower price, he came back to tell us. We saw him again a few months later when his car was towed in with an expired water pump, that stripped the belt and bounced the valves off the pistons.

 

It's a diesel engine, compression ignition, which means that the compression ratios are quite high. The majority of lower compression ratio petrol engines are not 'safe', so I doubt that there are any 'safe' diesel engines.

[geolee]

So this is what caused the problem (see picture). A part of the tensioner system snapped and the ball bearings were loose (as far as I could understand from what the mechanic was saying...I'm essentially technically challanged). I don't know what can cause this kind of thing but the mechanic says it is a manufacturing issue.

[Conniff]

Of course, a manufacturing problem, no way could it have been overtightened, silly me for thinking such a thing.

[geolee]

Of course, a manufacturing problem, no way could it have been overtightened, silly me for thinking such a thing.

 

So you think this could be caused by having the belt too tight?

[Conniff]

Of course it 'could' have, proving it is an entirely different matter. You won't be able to say 'you're fault, it was too tight'. You can ask to see the makers tightening figures and the tightening guage which he should be able to put his hand right onto if he has them. If not, then you can argue the point that you believe that it wasn't fitted in accordance with the manufacturers instructions.

 

It can also happen to a correctly fitted belt where the bearing has a manufacturing defect.

[geolee]

Of course it 'could' have, proving it is an entirely different matter. You won't be able to say 'you're fault, it was too tight'. You can ask to see the makers tightening figures and the tightening guage which he should be able to put his hand right onto if he has them. If not, then you can argue the point that you believe that it wasn't fitted in accordance with the manufacturers instructions.

 

It can also happen to a correctly fitted belt where the bearing has a manufacturing defect.

 

Of course, I can't prove that the belt was too tight, but the tensioner that snapped was part of the cambelt kit that he replaced (and he conveniently failed to mention this...I only found that the tensioner is part of the cambelt kit after seeing pictures on the internet...again I'm mechanically challanged). So he either charged me for the kit and didn't replace the tensioner (altough it looked quite new, and the car is 10 years old) or he replaced the tensioner and it snapped for some reason. In either case, however, he should be accountable for the failure and if he considers it was a manufacturing defect he could take the issue to the place he bought the kit from. Therefore I don't think I should pay for another kit or for whatever needs to be done to the engine as a result of this failure. Does this sound reasonable?

[Conniff]

You said he will come back on Monday - so has he come back and refused to do anything ??

 

Of course, a manufacturing problem, no way could it have been overtightened, silly me for thinking such a thing.

I was just highlighting how he so quickly jumped in with manufacturers fault when there could be a few reasons.

[geolee]

You said he will come back on Monday - so has he come back and refused to do anything ??

 

I was just highlighting how he so quickly jumped in with manufacturers fault when there could be a few reasons.

 

He came on Monday and took the car to his garrage. He says he will fix it but has mentioned that it will be an expensive job. He also said he'll call the manufacturer about the part that snapped, so he's not admitting in any way that it could also be his fault.