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Cam belt positioning on pulleys?

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I've just changed the cam belt on my '84 Excel. It took me a while - my 1st time and taking a lot of care. Engine starts & runs OK, but I notice that the belt seems to sit towards the back of the pulleys. The whole belt seems to sit quite a way back, noticeable on the cam pulleys but really obvious on the aux pulley, where it sits right back, leaving a big gap at the front but none at the back. It sits in a similar position on the tensioner (semi-auto tensioner on my car).

The belt is a (trapezoidal tooth) gates 5146, whereas the old one was the Lotus part. I didn't take a lot of notice of the position of the old belt before I took it off (note to self: should always take pictures before dismantling) so can't really compare. Also the Gates belt is a little narrower than the Lotus one.

Anyone got any views on this? Should I be worried? Have I put something together wrong?


PS I've attached some pics - one showing the belt position on the auxilliary pulley and the other showing it on the cam pulleys.

aux pulley - belt position.jpg

cam pulleys - belt position.jpg

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5146 is the correct belt.  It is only 1mm narrower. If the entire belt is on the pulleys then I wouldn't be overly concerned. Have you started the engine yet?   Have you done any other work on the car?   

British Fart to Florida, Nude to New York, Dunce to Denmark, Numpty to Newfoundland.  And Shitfaced Silly Sod to Sweden.

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I asked Mike Taylor at LB about this and I seem to remember  he told me that the belts tend to run towards the engine side of the pulleys and they are ok provided they are not rubbing against anything. I noticed that mine moved slightly forward after an hour or two of running..

If you have everything else correct you should be safe, the only other thing to check is the actual tension, you might have the belt too tight or loose

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Thanks for all the responses - they're all very much appreciated. In reply to some of the questions:
- Gates 5146 is indeed the correct belt for my '84 (LC) Excel.
- Yes I've started and run the engine (and rechecked the tension once cool).
- As well as changing the belt, at the same time I've serviced the tensioner using SJ's overhaul kit (bearing, piston, bushes, washers, earth strap) and replaced the alternator & PAS belts.
- I used a Krikit gauge to set the tension, plus the twist test. I'm aware there's a lot of discussions around belt tension setting so I'm just hoping it's set correctly. I'm actually tempted to visit my local Lotus place to get it checked (probably Sportmotive) - if only to set my mind at rest.



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