Timing Belt Work Around.

[ScaniaPBman]

I have done several timing belts here at home and the biggest problem with the job to me is having to remove and refit the crankshaft bolt to allow removal of the belt itself.

It seems to me that the only reason to remove the bolt and crank pulley is that the belt is inside the bottom plastic belt cover behind the crank pulley and this cover must be taken off for access to the  belt.

Now if I decided to just remove the belt bottom plastic cover in bits I would then have easy access to the belt so that I could fit the new belt straight away. Since I have not disturbed the location of the crankshaft belt pulley on the crankshaft then restoring the engine timing with the new belt would be straight forward.

This then leaves the problem of the exposed belt area around the crankshaft. By obtaining an intact bottom cover from the scrapyard or, perish the thought, from a Ford dealer cutting it in half and putting back in in the correct position, the protection would be restored.

So experts, what have I missed with my cunning plan?

By the way my next belt job is due in the summer months on my old ti-vct 1.6 petrol. If you can't find any flaws in my plan I will give it a go.

ScaniaPBman.

[ferretfloozy]

if the bottom pulleys not removed the bottom sprocket will not be free moving so how will you get the correct tension on the belt? the top cams will be locked

[AntonovAN12]

I have read about others breaking the bottom cover off and replacing it with one that has been cut into two halves to fit around the pulley. However, from looking at the photos in the manual, it doesn't seem that breaking it off would be that easy.

To tension the belt, could you not just rotate the engine a few times by hand once the belt is in place, then tighten the tensioner bolt?

I have done timing belts on a Honda D Series petrol engine and a Mitsubishi Shogun 2.5l Diesel. Both of those belts are tensioned in the same way.

However, both of those engines have keyways on the crank and cam shafts for the sprockets. They also have permanent alignment markers on the sprockets and the engine casing.

I have wondered about doing it that way on the 1.6 Duratec by setting the engine to TDC and then adding timing marks to the sprockets and engine with white paint. I don't see why you couldn't manage without having to remove the valve cover at all.

 

 

[ScaniaPBman]

Anton,

I agree it might be  bit of a challenge to remove the bottom cover in bits but the alternative of removing starter, bolt, pulley, rocker cover and replacing those bits along with torquing up a new bolt feels even worse. Also a split bottom cover will not be a compete and proper seal however I am prepared to accept this.

Since this job will be done on a ti-vct which needs an X shaped tool to lock the camshaft variators you are right, perhaps the rocker cover does even need to be taken off.

The Focus has done 150,000 miles and is currently on it's second belt right now. I am prepared to try out a few short cuts if it makes things easier.

Thanks for your comments,

ScaniaPBman.

[AntonovAN12]

As a correction to my last post, the Honda and Shogun belts are tensioned using the tensioner spring alone, before the engine is rotated. The tensioner is temporarily fitted with its spring fully compressed and adjuster bolt tightened to hold it in the compressed position. Neither of those engines have any holes for crank locking pins.

Once the belt is fitted with the marks correctly aligned, the tensioner bolts have to be loosened. This allows the spring to move the tensioner wheel against the belt. Once this is done, the tensioner bolts are then torqued tight.

The cover, crank pulley and bolt should then be refitted. The next step is to rotate the crankshaft by hand through a few full turns to ensure the marks stay properly aligned and everything turns smoothly.

In theory I don't see why this method wouldn't work on the Duratec engine if the crank and camshaft sprocket bolts were never loosened. Everything would hopefully be kept aligned by the paint marks.

I have actually seen a few older Escorts with earlier versions of this engine at car shows with the bonnets open. They were running without any timing belt covers at all.

 

[ScaniaPBman]

Over and above the obvious function of a timing belt cover to keep fingers away from rotating belts and keep things relatively clean there is the cold weather protection from snow packing.

In my previous job we would run a test car close behind a car which would leave a cloud of powdered snow behind it. The potential failure mode was that if the belt cover was not a good fit, the snow crystals would land on the toothed part of the timing belt and build up to a substantial lump causing early failure.

If there is snow like that about here in the UK I will be stopping at home.

[AntonovAN12]

I have also seen it said that we do not get very sandy or dusty conditions here in the UK, so belt wear from those is not as much of a problem.

If extra belt wear was an issue, having a split cover or no cover would make it easier to change more often anyway.

[rd457]

On 3/26/2022 at 2:22 PM, ScaniaPBman said:

By the way my next belt job is due in the summer months on my old ti-vct 1.6 petrol. If you can't find any flaws in my plan I will give it a go.

I'm a bit late replying, and I don't know if you've yet attempted this yet [you actually said in the other thread you've not tried this yet], I'm just responding in connection with you having suggested this hypothetical solution to someone in another thread...

I think you may find that this isn't feasible, though of course it may depend upon the precise year/model. Take a look at the picture below. I had this saved from previous research for my Mk2+FL non-Ti-VCT focus. Note that (1) the crankshaft pulley overlaps almost the entire lower cover, making it impossibly difficult to cut it away in place, and (2) at least two of the three cover bolts are overlapped by the rim of the pulley, making them impossible to remove/insert with the pulley in place. So you're going to have to take that pulley off at least once to modify the cover, but even then you're unable to remove/fit such a cut in half cover with the pulley in place.

Furthermore, with respect to the "cut in two" plan, no one so far seems to have raised the point that the cover is acting as a spacer between the belt cog and the pulley, so for fairly obvious reasons you'd have to modify any "cut in two pieces" plan into a "cut into three pieces" plan. Wait, no, on second thought that's wrong. I was looking at another picture when this thought occurred to me, but I mistook what I was looking at and failed to think that it made no sense with respect to the cover remaining stationary while the rest turns, so please ignore this paragraph.

[ScaniaPBman]

Thanks for your reply.

It looks as if you have found a stopper in my cunning plan.

ScaniaPBman.

[isetta]

On my previous 1.6tdci I cut the cover in half so I could get to the tensioner and water pump without removing the crank pulley again.  I removed it all to replace the belt but when reassembling I cut the cover In half just in case.  Never needed to get back in there.    When I replaced timing belt on a 1 litre lupo , vw made it easy, the pulley was held on to the central boss by 4 Allen key bolts.  It just needed those undoing. The central bolt did not need undoing at all. 

[mattsminiresto66]

re-read Ferretfloozys post,  there are no timing marks or keyways so the cams and flywheel should be locked, bottom sprocket has to be free spinning to allow belt to tension correctly on the Ti-VCT engine.