Timing belt or chain
QI have a 2007 Ford Focus TDCI 1753cc which has done 61,000 miles. I know the car has never had a timing belt change and there could be two of them! I understand there is always a top timing belt, but I am unsure for the lower part if there is a chain or belt-in-oil (BIO). Perhaps you are able to help?
I have read that the tensioner pin (behind the aircon pump) can answer my question, ie. flat or round end; is this correct? Can it be simply removed without any risk to the timing, or should I take steps to secure the engine?
My next question is regarding the turbo oil feed.
I have been told if there is a BIO then this oil feed can become blocked at the mesh filter. Where is this mesh filter located, and can it be cleaned or removed with a sharp tool?
Lastly, should I need to replace a BIO is it advisable to use sealant (Wellseal) around the lowertiming-chain case gasket?
Thank you for all your help.
Andy Nash
AAs you have discovered, the low drive to the fuel pump may be via a chain or a belt which runs in oil. Whichever choice is fitted, the replacement time for the chain and the belt are both given as ten years or 125,000 miles. So whichever system the engine is fitted with, the lower drive according to the Ford schedule needs to be renewed.
This method of checking which, as you have mentioned, is to look at the tensioner head, which if silver will indicate a belt is fitted and if black will indicate a chain is fitted. Many prefer to replace the lower belt with a chain – and kits are readily available for this if preferred. As you supplied your details, I can see that the lower drive on your KKDA engine is driven by a chain.
The turbo oil feed I suspect you are referring to is the main oil pickup via the lower mesh strainer in the sump, which if the belt is beginning to shed tiny particles, can become partially blocked, and it would be necessary to remove the sump to access and clean this.
My own personal preference is to use Wellseal when fitting the engine gaskets in place, as it provides a good seal without the disadvantages that can be experienced with silicone sealants.
Replacing the upper timing belt was covered in the February 2014 edition of Car Mechanics when we had an early Focus 1.8 TDCI as a project car.