Xantia 1.8 16V cam timing - weird settings?

handyman · Post by **handyman** » 31 Mar 2010, 18:47

Sods law, we are due to go away and the Xantia waterpump springs a leak!

This is the latest iteration of the XU7 lump fitted to a 2001 Xantia.

On stripping down the belt drive to replace it and the waterpump, I am perplexed to see that the cams and crankshaft markings are out of alignment to the relevant timing holes. Both the cam sprockets align with their indexing holes in the head, but this then leaves the crankshaft pulley out by about 60deg advanced, if the hole in the pulley is correct. The alternative, of aligning the pulley leaves the camsprockets way off their locating holes.

Am I missing a trick here? I have checked the markings on both sides of the four stroke cycle.

The engine was running really well, prior to the leak, and, as far as I am aware, has not slipped the timing belt. It rotates easily with a spanner on the crankshaft bolt, with no nasty valve to piston noises.

The badly edited writing and the poor photos in the BOL seem to offer no help, even though my copy is for Mk1 models.

Could it be that the pulley has been swapped at some point for a unit with a different timing hole?

What is the position of the crank supposed to be if it is in correct alignment with the cams? IE, angle of the woodruff key or position of No:1 piston for cam timing.

I am getting it in the neck as we are supposed to be off tomorrow to beat the Easter hordes, so any thought or help will be appreciated.

Handyman

Post by **CitroJim** » 31 Mar 2010, 19:06

Is it a manifestation of the nasty problem on the 2.0 TCT engine where the timing hole is on the outer annulus of the dual-mass crank pulley and any slippage between inner and outer will put the timing hole out of alignment?

If so, maybe the old Activa trick of using a solid crank pulley from an early XU engine will work?

Usually the engines are timed when all pistons are midway in case of timing accidents so you can't rely on any piston being at TDC when the timing pins are in.

It's a shame the petrols don't have the indexing hole in the flywheel like the XUD. Or do they? I've never looked but it might be well worth a poke about behind the starter...

Otherwise it's from scratch using a degree wheel and knowledge of the cam timings relative to TDC...

spider · Post by **spider** » 31 Mar 2010, 20:32

CitroJim wrote:It's a shame the petrols don't have the indexing hole in the flywheel like the XUD. Or do they? I've never looked but it might be well worth a poke about behind the starter...

I don't think the XU petrols do have this, (unlike the TU's as you know) , they rely on the hole and 'space' (for want of a better word) in the pulley / block casting.

I don't know if the later ones are the same, I vaugely remember a few earlier ones (say around 98 where the rubber pulley had split) the 'cure' was a new pulley (even if just temporary to get the holes aligned properly.

It's not something you can tell is 'broken' in most cases until you take it off.

The very early solid pulley's I am not sure about if they are the same regarding position etc.

Disclaimer: I've probably only changed about half a dozen XU8J / XU10J belts and the last one was about five years ago so I can't remember every detail, hopefully thats a bit more info though.

Deanxm · Post by **Deanxm** » 31 Mar 2010, 20:34

I know the holes are in the block on the XU petrol engines, just no locking point in the Auto flywheels although im sure they are there on manual transmission models.

D

handyman · Post by **handyman** » 31 Mar 2010, 22:21

The crankshaft pulley shows no signs of deterioration or disintegration. The rubber bonding is all in good order and the whole pulley assembly is tight.

As I am on limited time tomorrow, I will just mark up the sprockets and fit the new pump and belt.

Handyman

Post by **CitroJim** » 31 Mar 2010, 22:27

handyman wrote:The crankshaft pulley shows no signs of deterioration or disintegration. The rubber bonding is all in good order and the whole pulley assembly is tight.

That's no guarantee it has not slipped. Every Activa pulley I've seen has looked absolutely pristine but the timing hole has always been a country mile out.

When all is back together, paint a line across the pulley and watch it for a few weeks...

Hope all goes well and you get away for the Easter break on time

handyman · Post by **handyman** » 01 Apr 2010, 06:58

Hi Jim, having thought about it, I have a solid crankshaft pulley on another 2.0L twin cam engine I have built for one of the Activas and I know the cam timing on that is correct. Just a matter of whizzing down to the workshop and robbing that one, even just to check.

This the first time I have come across this phenomena and I have fitted a few cambelts to PSA engines, all without any trouble.

Handyman

citronut · Post by **citronut** » 01 Apr 2010, 08:40

Jim wrote
"Usually the engines are timed when all pistons are midway"

all the XUD lumps i have had heads off, whilst timming pins are in place No. 1 and 4 are always at TDC Sir Jim, in fact i think the 1,8 16V XANT i did a few years ago was the same

regards malcolm

Post by **CitroJim** » 01 Apr 2010, 09:02

citronut wrote:Jim wrote
all the XUD lumps i have had heads off, whilst timming pins are in place No. 1 and 4 are always at TDC Sir Jim, in fact i think the 1,8 16V XANT i did a few years ago was the same

Oh, that's excellent Malcolm. Makes it dead easy to time from scratch then...

Goodness knows where I got the idea about them being halfway down came from. Must have drempt it or someone put something in my tea...

addo · Post by **addo** » 01 Apr 2010, 10:13

405 XU9J4 is like that.

Deanxm · Post by **Deanxm** » 01 Apr 2010, 18:02

My 2.0 XU petrol engines in the xm pin all pistons at half mast, they do on the tct engine im rebuilding/tuning at the moment too which is the same block and head just with some extra drillings in the block................

D