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Timing belts in oil future problems ?

89K views 95 replies 24 participants last post by  danjh78  
#1 ·
I went to the local garage to pick up a new boot liner for the Car, and when I came out I had a mechanic tell me to I should get rid of my mk8 st as those timing belts running through oil will cause lots of problems. Then he just strolled off which left me pondering. I’ve had a browse online but it’s turned up little info perhaps I’m looking at the wrong stuff.
Has anyone has any issues ?
 
#4 ·
Looks like it is a chain, I was sure it was

 
#5 ·
I went to the local garage to pick up a new boot liner for the Car, and when I came out I had a mechanic tell me to I should get rid of my mk8 st as those timing belts running through oil will cause lots of problems. Then he just strolled off which left me pondering. I’ve had a browse online but it’s turned up little info perhaps I’m looking at the wrong stuff.
Has anyone has any issues ?
I wouldnt worry, he was probably a VW fanboi or a German car owner at least, green round the gills etc etc !
 
#6 ·
The 1.0 ecoboost engine which started out in 2012 is the one with the wet belt. It runs through the engine oil. There have been some issues where material from the belt has blocked the engine oil pickup and hence starved the engine of oil. I read somewhere that this is worsened if you don't use an oil specially designed for wet belt engines.
The belt is supposed to last something like 10 years or 150k miles before it needs replacement - and it's obviously a big job. Due to a significant number of failures, you'll find some people recommend halving that service period.

The good news is the 1.5 ST engine, as has been summised above, uses a chain for timing.
 
#17 ·
Even the initiated are getting lost.

Cams are chain, only likely service item would be tensioner. That is the good bit. No cam belt to fail and write off the engine.

The oil pump is unusually a small belt in oil, probably a lower friction thing, but obviously could fail and cause oil starvation. But this should immediately bring up low oil pressure warning before any mechanical damage.

The rest of the serpentine belt is water pump, air con, alternator . .
 
#21 ·
Yes the diagram is the naturally aspirated one (wet timing belt on that one) I posted that just to show the set up clearer than the haynes auto fix diagram.. If you look at the youtube link i posted above showing the turbo dragon fiesta st engine it shows the same set up gear driven off the balance shaft..The haynes autofix screenshot i posted shows the same aswell...I confirmed with a guy i know works in ford parts department at my local main dealer but as i said above mines derivative 2 my sons is 12 so newer ones maybe wet oil pump belt I doubt it myself but if anyone has any doubts they should just ask their parts/service dept at their dealers..
 
#29 ·
You must know the build Date of your car. And look for the outer appearance of your engine/of the front timing chain cover . The registration date is unimportant if you look for technical information.
 
#30 ·
This is so confusing. My engine is a Derivative 1 and the engine was built on 16/5/2019. It has 6.1 Litres of oil and the dipstick is 48.5cm long, but according to Mountune mine has a blow off valve as well, so it seems like mine is a Frankenstein car with some earlier bits and later bits. All i want to know is do i have a timing belt or timing chain 😄
 
#32 ·
Let's start at the beginning. 😅
Every 1.5 litre 3 cylinder engine has a timing chain for Crankshaft to the 2 camshafts. The interesting question is if the engine got a little oil pump belt or gear driven oil pump. Only few engines have the older construction with balancer shaft in Oil sump and Oil pump gear driven.
The majority of the engines have the newer construction with upper balance shaft, and belt driven oil pump.
 
#36 ·
Just to continue the oil pump belt discussion, I stumbled across the following when I was browsing the service schedule for the ST -

  • Oil Pump Belt -- Every 150 000 miles/10 years - Renew (LTS 21 716 5) Vehicles built from 02/25/2019 only
So it appears there is actually a replacement interval specified for this belt. And I have to say it looks like a pig of a job.
The belt is driven by the crankshaft, so there's quite a few steps to being able to get it off -
Starting at the bottom, -
1) Remove the undertray
2) Remove the sump
3) There's a cover over the oil pump drive - take this off then you can slide the belt off the toothed pulley on the oil pump
Then we're on the front of the engine -
1) Remove the auxiliary belt and then the crankshaft pulley
2) Remove the timing chain cover
3) Take the timing chain off so you can get the timing pulley off the crank
4) Remove the balancer shaft drive pulley
- that gives you access to the oil pump drive pulley, so you can get the belt off.

Reassembly is the reverse 🤣 - including setting the cam timing etc.
There's lots of single use parts to bin (plus seals and gaskets), and after 150 k miles or ten years, you might as well think about other bits to replace.

That lot is going to cost a few quid unless you do it yourself. I wonder how much Ford would charge and how many people won't bother.
@Jorg - do you know how many hours the Ford system suggests for this job?

Cheers,
MarkP
 
#39 ·
Late to the party on this thread, but Ford themselves may have caused confusion here. When the Mk 8 ST was launched, I downloaded the technical specs from media.ford.com (2018FordFiesta_ST_TechSpecs_EU.pdf).

This said: "Camshaft drive: Low friction belt in oil with dynamic tensioner"

I have just downloaded what seems to be the current version (FordFiestaST2021_TechSpecs_EU.pdf)

This now says: "Camshaft drive: chain driven with hydraulic tensioner"
 
#41 ·
Yes, I was very surprised to find that incorrect information from Ford back in 2018 and reassured myself by checking as many other sources as possible. Obviously they have corrected the document since. Many thanks for your own input on this thread which is very informative.

Shame about the oil pump drive though. I still have memories of the ease with which you could remove the externally mounted pump on the "Kent" engine!😀