Cambelt Change on Xantia 2.0 Turbo

Post by **CitroJim** » 07 Mar 2007, 08:53

I've just ordered a cambelt and tensioner kit (and water pump!) for the Activa. I'm never truely happy with a new car until I know it has a new cambelt and water pump.

Is there anything specific about this job and any points I should watch? It'll be my first time on an XU10 8V engine with the eccentric tensioner although I've done bucketfuls of cambelts on XUDs and early XU engines.

How best to set the tension without the special tool? Is checking that you can just do a 90 degree twist on the longest run OK?

Thanks...

alan s · Post by **alan s** » 07 Mar 2007, 09:23

I have done a couple of 8 valve 2.0i engines, no dramas.

I felt a bit more secure in my own mind by dropping the entire tensioning set up out, and then with first hand knowledge of what it consisted of, I had no dramas when I refitted and tensioned it.
I usually firstly turn by hand when I do a cambelt, then use the starter and look for any irregularities, then fit the bottom pulley as a bit of security and start the engine through the drivers window whilst watching the belt. If it looks flappy, I tighten and retest and if it whirrs, I slacken off & retest before fitting the covers.
Not a real big job nor all that complicated. I made it a bit more complicated than it needed to be, but I felt happier doing it that way. Others seem happy to just grope around using the cam eccentric.

Alan S

Post by **RichardW** » 07 Mar 2007, 12:03

Watch out for the crank pulley having rotated relative to itself, making it impossible to time the engine!

Mandrake · Post by **Mandrake** » 07 Mar 2007, 18:49

RichardW wrote:Watch out for the crank pulley having rotated relative to itself, making it impossible to time the engine!

The timing holes were not in alignment on both the engines I did the belts on - they were out by about half a hole while the original belt was still fitted, making it impossible to use pegs.

Apparently this is pretty common on the 8v engine, your best bet is to mark the pulleys and belt with whiteout, remove the belt, copy the markings to the new belt and fit it - can't go wrong that way.

Because you usually need to give the bottom pulley area a good clean with petrol after removing the belt due to oil and dirt buildup, as an added precaution I put some scratch marks on the side of the teeth on the bottom pulley as well, in case the whiteout pen marks washed off...

As for the tension, you will need a special tool to adjust the eccentric - I made one from a short piece of 8mm key steel welded into a 3/8" socket. Setting the tension without a gauge is a "fun" exercise. Obviously you don't want it to be flopping around, but equally you don't want it overtight.

If you hear a strange whirring/warbling noise that peaks around 1500rpm you know you have it too tight - back it off a bit! Bear in mind that the belt will get a lot tighter when the engine heats up due to expansion of the head and block!

The tension might seem ok while cold but then when it warms up after a few minutes it may be too tight and make that funny noise.

Remember not to run the engine without the bottom pulley bolted on - its ok to run the engine for short periods of time without the auxillary belt fitted though.

Regards,
Simon

AndersDK · Post by **AndersDK** » 07 Mar 2007, 20:12

If you have some sort of a torque tool made up for the tension, then you can use a cheap and common Dynamometer. Also known as a fish-weight or spring weight.
Its nothing but a calibrated spring in a tube, with hooks both ends. Available in every thinkable size/weight range.

If you know the arm length of the torque tool (center to spring hook attachment), then you calculate the tension by : 'armlenght x spring reading', which would have 'kgm' as units.

alan s · Post by **alan s** » 07 Mar 2007, 21:07

I used an old refrigeration tool to work my eccentric, a 1/4" valve key.

I forgot about the pulley business mainly because whenever I do a cambelt, I always use the belt and sprocket markings with a Tippex pen as a back up to ensure the belt goes on as it comes off. (Thank you for that tip a few years back Anders)
Possibly the easiest cambelt job I've done on a Cit.

Alan S

Post by **CitroJim** » 07 Mar 2007, 21:56

Thanks all for a wealth of information. This forum really is a godmine.

Mine does whirr a bit but only when cold and this is one reason why I'm keen to swap it. A label in the engine compartment attests to the belt only being changed 7000 miles ago but in mid 2005 so I don't altogether trust the present mileage reading. It had stood for a long while before I acquired it but 7000 miles in 18 months still seems a bit low to me. Better safe than sorry.

Your talk of spring balances reminds me Anders, many years ago when we stopped overhauling the old mechanical teleprinters at work I rescued some of the tools we used to use before they went in the skip. This included a set of precision balances. I knew they would come in useful one day