Xantia hesitates...now won't start

Toby_HDi · Unread post by **Toby_HDi** » 24 Dec 2008, 19:17

As many know I have been having trouble with filling my cooling system. Today I tried again as I was in a patient mood and I got it all sorted.

I decided I would take it for a trip to get my lunch and to shake it down. I went to town - all fine. I then went to the fuel station and filled up with diesel. I get 2 miles down the road and the car hesitates and I see white smoke in the rear view mirror.

On pulling over the engine was idling very rough so I killed the ignition and checked all was ok with the cooling system (showed no signs of overheating or anything) and all seemed fine. I tried to start again and it wouldn't start, it not turns over on the key, nearly catches and then just continues to turn on the starter without firing. What's going on? We first thought I'd misfueled it but thats now been ruled out. Has the cambelt jumped a tooth? Or would I have noticed this with pistons meeting valves?

Any help appreciated - not having much luck atm

Thanks

Unread post by **CitroJim** » 24 Dec 2008, 19:56

Gosh Toby, what a time for it to happen

My first guess is that it's something you disturbed when doing the recent work. Have a check of the crank and cam position sensors and any wiring in the vicinity for connectors hanging loose...

It sounds like the injection timing went a bit out of kilter just before, again pointing to a sensor signal being lost.

Did the Engine Management Light come on?

It'll be something simple...

Toby_HDi · Unread post by **Toby_HDi** » 24 Dec 2008, 20:29

No EM light, it was idling for 15-20mins fine while doing the coolant (thanks to Mandrake I believe for his tip on loading the engine to warm it up) and while I went to town.

I also accelarated hard to merge onto the dual carriageway and all was fine then. It was as I was settling down to cruise that it happened.

I will check all sensors, is there anything else it could be? Can my mind be eased and it confirmed (as good as can be without looking at it) that it is not the timing belt? I wonder if one tooth would be enough to cause the pistons to hit the valves.

As you say, possibly something simple but it really got me angry as I had to be trailered home on a flatbed

Thanks

EDIT: Just been out to car to get something and noticed the courtesy lights not working (one in footwell does but not two on B pillars). A fuse perhaps that connects the problems? OR mere coincidence?

DickieG · Unread post by **DickieG** » 24 Dec 2008, 23:33

It could well be down to the the timing belt jumping a tooth, the good news is that should that have happened the engine 'should' cope

. White smoke does point to such an occurrence.

As for the lights issue I wouldn't have thought it is connected.

Unread post by **lolingram** » 25 Dec 2008, 10:50

I decided I would take it for a trip to get my lunch and to shake it down. I went to town - all fine. I then went to the fuel station and filled up with diesel. I get 2 miles down the road and the car hesitates and I see white smoke in the rear view mirror.

Have you carefully checked tank contents? Remembering this occurred shortly after fillup...

Toby_HDi · Unread post by **Toby_HDi** » 25 Dec 2008, 11:54

lolingram wrote:Have you carefully checked tank contents? Remembering this occurred shortly after fillup...

Yep, almost certainly diesel I put it. Not had a petrol car for so long and with the works van being diesel I pick up the black pump automatically but I did check too.

Going to have a look at it today so hopefully I'll find the cause.

Thanks

Unread post by **lolingram** » 25 Dec 2008, 12:48

Yep, almost certainly diesel I put it. Not had a petrol car for so long and with the works van being diesel I pick up the black pump automatically but I did check too.

I meant that your recent top-up may have a dose of the clap!

Unread post by **CitroJim** » 25 Dec 2008, 14:20

If the timing belt has slipped, the tension adjustment may be the cause. I believe these are the same manually adjusted tensioner as on the later 8V XU engines.

You need to be careful setting the tension and when cold it needs to be set a little on the slack side to compensate for the expansion of the engine as it gets hot and thus tightening the belt.

Adjust it cold so you can easily twist it through 90 degress on it's longest run (between cam and HP pump) and you should be OK.

If the cambelt sounds "whiney" when the engine is hot then it's too tight.

Toby_HDi · Unread post by **Toby_HDi** » 25 Dec 2008, 14:45

Right I'm in to the timing belt (amazing how much quicker it is after you've done it once. It has slipped a tooth - with the flywheel locked the cam sprocket hole is just out.

Now, how do I rectify this? I cannot seem to turn the camshaft using the hub bolt.

Yes, Jim its a manual tensioner that requires the use of a square section key - not having had experience of the 8v XU I do not know if it is the same. I believe it may have been tensioned too tight as it seemed to be too slack when I could rotate it 90 degrees. However, I will tension as such after I've re timed everything.

Quite nice being out there today

Thanks

Unread post by **CitroJim** » 25 Dec 2008, 14:55

Hi Toby,

Lock the crank and slip the belt right off. Then you can rotate the cam sprocket on it's centre bolt (or even by hand) until the hole lines up and you can pin it. Then slip the belt back on.

Yes, that's the same tensioner as on the 8V XU exactly.

Tension cold so you can twist the belt 90 degrees fairly easily.

If you can, run the car with the covers off so you can recheck it hot. The belt then sould be at such a tension that you can just about twist it 90 degrees between finger and thumb.

In any case. Run the engine for a bit, say an hour, and then recheck the tension. I find this an essential step on any engine with a manual tensioner.

I'm hiding in my daughters bedroom whils Christmas dinner is being prepared

All the best Toby. Wish I was out working on a car today.....

Toby_HDi · Unread post by **Toby_HDi** » 25 Dec 2008, 15:01

Thanks Jim, does this mean the centre bolt has to be loosened? Or not?

If not, then I'm just worried about pulling the engine off the jack as it's FT

Just had dinner, am in hiding too

Unread post by **CitroJim** » 25 Dec 2008, 15:10

Toby_HDi wrote:Thanks Jim, does this mean the centre bolt has to be loosened? Or not?

No, should be no need to. If you slacken the tensioner fully, the belt should slip off the cam sprocket with no need to disturb the crank end. Keep a bit of upward tension on the belt as it comes off the cam sprocket so that there is minimal risk of it jumping off the crak sprocket. You don't need to fully remove it, just enough that you can rotate the cam sprocket back into time.

Thank goodness you don't have to retime the HP pump as well!

Do rotate the engine by hand a good few revolutions though to ensure positively that the belt is properly engaged on the crank sprocket as you wont be able to "eyeball" it.

I'd rotate the engine at least six full camshaft revolutions and carefull recheck timing and tension before being content.

Toby_HDi · Unread post by **Toby_HDi** » 25 Dec 2008, 15:13

Thanks Jim...

Will report back later...

Toby_HDi · Unread post by **Toby_HDi** » 25 Dec 2008, 15:53

Well, it's starting to get too dark now so I've come in.

I just cannot rotate the cam sprocket any further clockwise - it's almost there but now it's solid, I don't want to shear that bolt either.

At a loss again now

Unread post by **CitroJim** » 25 Dec 2008, 17:14

Toby, It's possible a valve is contacting a piston crown although very unlikely if it were only a tooth out.

The cam can seem to have very tight spots in it, depending on how many valves are being opened at the time. On reflection, it's best to rotate the cam by hand on the edge of the sprocket; you have more torque available that way compared to trying to rotate it very far on the centre bolt.

If the engine goes absolutely rock-solid at any point, it is likely a valve is contacting a piston and the timing may therefore have ended further out than first thought. STOP.

If so, Unlock the crank and rotate it a few degrees away from the timed position so that the two pistons that are at TDC travel down the bores a bit so there is adequate room for the valves to move freely. Don't go far, say 10-15 degrees. It it locks solid at any point, STOP.

Then, if you were able to rotate the crank the required distance, very carefully try rotating the cam again and see if it'll move past the spot it seemed to lock in previously.

You may have to jiggle the cam and crank both backwards and forwards by small increments until everything sorts itself out and the timing marks line up.

I had to do this on a TU engine, moving the crank and cam a little at a time until I achieved time. That engine had completely lost time.

Don't, under any circumstances, force anything if the engine seems to be locked.

When it all comes back into time, you need to carefully check the belt for lost/damaged teeth.