I have just done a load of work on the car (2008 1.8 TDCI Focus) and the upcoming job is the lower wet belt. I might get it done professionally if the money is sensible. Otherwise will tackle it when there is a full week dry (maybe some months away!).

Local Ford dealer checked my car on their system and said I have a belt. That's not what I wanted to hear (and will check the tensioner myself) but they're likely right.

So called a mechanic shop (recommended by the council guys who look after the police cars, etc, which they use when they have too much work) who are also a Ford specialist (so the council guys told me).

They said they would not do belt to chain conversions, but only replace belt with belt. I asked why. They said because the plastic cassette (which is on both chain and belt) can get smashed up over time by the chain (not by the belt) leaving loose bits of plastic in the housing causing problems. 

That's not something I have heard of before, but if true ( and as we know there are a lot of unfounded rumours on all sorts things) would be a serious concern.

Has anyone heard similar about the chain chipping of bits of the plastic cassette?

6 hours ago, TDCI man said:

(2008 1.8 TDCI Focus) and the upcoming job is the lower wet belt.

Wet timing belt ?

You learn something new everyday. Can you confirm this @TomsFocus please ?

10 hours ago, unofix said:

Wet timing belt ?

You learn something new everyday. Can you confirm this @TomsFocus please ?

Yes, the 1.8 TDCI engine has had a wet timing belt since Mk2.5 Focus.  That runs from crank to fuel pump.  Then there is a short dry belt from fuel pump to cam.

Interestingly, that engine previously had a chain in the same configuration, which is why they can be retrofitted to the later wetbelt engines.

I've never heard of the chain guides breaking up on these.  It is an issue on other chain engines, some BMW engines most recently.

Thanks Tom and Unofix.

Tom, you're right, seems Beemers suffered quite a bit. A former Beemer man I reckon their quality dropped around 2003/4 time onwards. Seems strange to me this garage said that they will not do a belt to chain conversion, even suggesting I might approach my local Ford dealer to do the job (thinking about it, if the official Ford dealer is willing to do the job, why not an independent ...? Odd).

From your last sentence sounds like you feel chain is the better option? From my reading it seems:

Belt:

Pros: quieter than chain, good for 10 years or 62k miles (Ford and Dayco say 125k miles, but seems nobody has faith in that). 

Cons: 62k miles is OK or not depending on driving needs, if the belt brakes, and it could do suddenly and catastrophically, it could wipe out the engine (i.e. uneconomic to rebuild).

Chain:

Pros: more robust than chain, may never need changing again. Little or no chance of sudden catastrophic failure as will give notice (i.e. change in noise) if there is a problem developing so that the problem can be addressed before it fails. 

Cons: noisier, risk of chain stretch over time (but probably only after very big mileage). Chomping plastic cassette (serious or not?).

Cost difference between belt and chain are marginal.

Personally, I am tending towards a chain, but still reading.

10 minutes ago, TDCI man said:

Belt:

Pros: quieter than chain

To be honest the 1.8TDCi is a fairly agricultural engine so I very much doubt you'd be able to tell the difference from a chain. It's a very bomb-proof lump though.

We ran an earlier 1.8TDCi with the chain and at that time I never read any reports of problems with it chewing the cassette. This is the first time I've seen it mentioned.

If it were me I'd go for the chain every time.

A Ford dealer won't make any modifications.  If your car was originally fitted with a belt, they will only fit a new belt to it.

The wetbelts on these don't seem to suffer as badly as they do on the newer EcoBoost & EcoBlue engines.  I would probably just fit another wetbelt myself, as long as you're keeping to the correct oil change schedule.  If I was buying a used car and had the choice, I do prefer chains as a general rule.  If the chain guides do break up, the valve timing can be lost quickly and cause catastrophic damage when the chain goes slack.  There should be a lot of rattling and rough running before it reaches that point though.

mjt & Tom. 

Yes, the 1.8 TDCI is an early 1980s engine and basically well-sorted, though as you say "agricultural" (I quite like it though!!). 

It may be that the independent saying no to a belt to chain conversion, had picked up on the Beemers and applied the same logic. They claimed to had had examples of plastic from the guide cassette in the oil. But this is the first time anyone on this forum (so far) seems to have heard of it with this engine ...!

The 10 year life of the belt does not worry me, nor 62k miles (will probably do a bit more in 10 years but not 120k). For me the main thing is a) belt can self-destruct itself (and engine) without warning whereas b) chain will give warning (through more noise / rattling) so can deal with the problem in good time.

I plan to put a bit of sound insulation in anyway, belt or chain, so not worried about the noise factor.

Tom, that the independent suggested trying the Ford dealer for the conversion but as you say that will only do like for like (I agree) makes me doubt the credibility of that independent in their idea of the cassette chomping timing chain too!

 

Couple of earlier threads on this:

https://www.fordownersclub.com/forums/topic/96358-18-diesel-wet-belt-conversion/

https://www.fordownersclub.com/forums/topic/130722-ford-focus-18-tdci-2009-wet-belt-or-chain-how-to-be-sure/

I think this is the kit:

https://www.lymmengineparts.co.uk/lower-wet-belt-to-chain-conversion-kit-for-ford-1-8-tdci-1562244

I don't recall ever seeing a thread on ANY of the Ford related forums I've frequented over the years where a 1.8 TDCi engine that had a lower chain instead of a belt had EVER failed.

 

Never once heard of the 'issue' the garage referred to in relation to this engine. Plus, the 'conversion kit' basically just contains the exact same parts as the engines that came with a lower chain from the factory (like my old 2005 MK2 Focus I owned for 12+ years). So I'd definitely be classing what the garage said about running the lower chain instead of the belt as being utter crap!

@FatHead As an Owner of a 1.8 TDCI I have done a lot of reading on this (as I'm sure many have). Like you, I've seen nothing in line with what the garage claim (chains chipping away at their plastic cassettes). That said, as Tom says Beemers suffered a bit from this for a while (but there's a whole load of other makes and models that have not).

My take is that it's 'easier' for the garage. Most usually prefer like-for-like replacement as it requires no thinking, and implicitly less risk of comeback (I.e.  avoids the "it's changed but I don't like it now" risk). Also like-for-like means no change in the timing (possible extra work going from belt to chain or vice versa). If they're busy enough anyway then why bother handling a conversion? I don't think there is much hard evidence or engineering science in their thinking though.

For me, the big difference is the matter of sudden catastrophic failure without warning. With a belt that's possible (though unlikely). With a chain it may just be possible but there'll be plenty of warning (noise, rattles, etc) long beforehand.

Anyway, have asked the garage for the wet belt cost, and also seeking a chain job cost. I may also do the job myself waiting untill next year, if their numbers are too high.