Xantia V6 broken exhaust (update: and rough low rpm running)

[Mandrake]

Hopefully we'll see next weekend, but given the number of blind alleys we've been down with it, I'm not getting my hopes up!!

Amen to that...

[CitroJim]

Hopefully we'll see next weekend, but given the number of blind alleys we've been down with it, I'm not getting my hopes up!!

Amen to that...

Yes but against that there are only a finite number of blind alleys. One has to lead somewhere and fingers crossed that alley will soon be found...

[Mandrake]

Ah just the man I was looking for.

I don't suppose you have the timing belt change/adjustment documents on file that you could upload before Saturday so I could read over them ? I have bits and pieces of it from various sources but the more information the better, particularly if you have any info on the old and new tensioners and their differences.

I'm not planning to remove the belt this weekend but if we did take the cover off and find the belt loose then we'd have no choice but to make an educated guess at tensioning it a bit better rather than knowingly leaving it flopping around...

Yes but against that there are only a finite number of blind alleys. One has to lead somewhere and fingers crossed that alley will soon be found...

Indeed. I'm satisfied that it is running lean under load and also that the engine is knocking under load - all that remains is to conclusively find the cause of both of these. Lots has been ruled out, valve timing (or a valve problem) is one of the very few things left and also fits both symptoms to a tee, although how the timing could have got out is unknown and somewhat worrying...

I am reassured though by the fact that the engine still performs absolutely flawlessly for the first couple of minutes after a cold morning start, and the cranking compression was excellent when tested (in fact unusually high) which makes valve damage unlikely.

Running well during a cold start also fits the lean mixture and excessive cylinder pressure theory - during a cold start the mixture is extra rich, and knocking would not happen as easily on a cold engine with cold cylinder walls, especially with a rich mixture. As the engine warms up and the mixture is leaned back out, then knocking (and timing retard and power loss) would start to occur.

I'm just crossing my fingers that we find the cam timing is indeed out, but not out so far that damage would have been caused...

[CitroJim]

Ah just the man I was looking for.

Damm I knew it was not a good time to raise my head above the parapet

Simon, I do and I'll post them up in a bit. I have both versions, one for the ES9J4 with the dynamic tensioner and one for the ES9J4S with the later springy tensioner so between them they'll tell you all..

I'll have to go to my other PC to find the links I need...

Be back in a bit...

[CitroJim]

Simon,,

Just for you:

ES9J4 Cambelt Replacement Guide

ES9J4S Cambelt Replacement Guide

and as a little billy-bonus -ES9J4 Auxiliary Belt Replacement Guide

Enjoy The PDFs are big and may take a while to download. Take care in downloading as they will be coming down the same pipe as the forum and that pipe is not very big... It might make the forum run a bit slow whilst they download...

[RichardW]

We had the aux belt off it last year to do the hyd pump seals - foxed us for a bit as to how to release the tension - even when we had found the instructions in docbackup

[CitroJim]

It's one of those that's not obvious is it Richard?

When you see how it works it's all deceptively simple and easy to do so long as you have a big 21mm spanner and a cranked 13mm spanner...


And three hands

[lexi]

I have still got a big cranked spanner ( 21mm ?) welded onto a bar for that job........made it easier.

[DHallworth]

Did you manage to get a look at your timing belt today Simon?

David.

[RichardW]

I'm surprised that Simon hasn't posted up, buy maybe he's still banging his head on the proverbial brick wall somewhere..... Fortunately for Simon's wallet, there was evidence of a previous belt change - tippex marks on the belt and some of the pulleys, and the belt looks in fine condition - no cracking on either side. Unfortunately for the running problems, the timing was more or less spot on We tweaked 3 of the cams, the front bank exhaust cam wouldn't quite go far enough to get it into exact time, but it's within a degree or so.

Sadly the OS sill collapsed above the jacking point as we were taking it off the stand, so that will need patching. Any tips for patching the sill there appreciated....

[CitroJim]

That's a shame Richard, I was really hoping that was going to be Simon's problem too... Ahh well, thinking caps back on...

Anglesey Paul (AKA the MIG Wizard) will be the best personage to ask about sill repairs methinks... I believe he's been there...

[lexi]

I am surprised with new timing belt. Wonder if it was a forced change?
Change a timing belt but oil filter has a custom label from about 5 years previous? Maybe they kept changing oil and leaving filter.
Ah well ...........saved Simon a few quid and car is still going. Maybe new car time.

[Mandrake]

Ahah, you stole my thunder Richard, and said in one paragraph what I was going to say in ten.

I'm not banging my head against a wall (much) all things considered, I just hadn't had a chance to sit down and upload some photos and post yet. I'm also pretty knackered from yesterday - my body is not used to hard physical work, so I was out for the count last night and slept late this morning, awaking to find my neck, shoulders, upper back, legs and even my backside stiff and aching. To the point that the soreness in every part of my body was making me laugh...(luckily it was a good soreness like that after a workout, not a pulled my back painful soreness )

A bit of a mixed day in the end - some things went well though, including the weather! There's not much to tell about the rear discs and pads job as it went ahead with no real snags - I'd phoned Pleiades last week to enquire about getting some calliper brake lines made up in anticipation of the old ones breaking or refusing to part company with the calliper, only to find they were out of pipe endings until next week.

So we carefully went ahead anyway without spare pipes, and with plenty of LPS and careful persuasion with a proper flare nut spanner both brake lines were out of the calliper without incident, and once the surface rust was off the nuts the hexes were actually found to be in pretty good condition.

Three of the four calliper bolts let go without a struggle, the fourth one needed a good bit of heat but relented. None broke. The discs came free with a simple tap with a hammer.

We were initially going to swap the callipers between left and right sides as the corrosion on the face of one calliper was pretty bad even after initial cleaning, but despite forum wisdom saying it's possible to swap left and right callipers over and replacement callipers having only one part number for both sides we could not!

It seems the inner drilling for the pipe union hole in the calliper is slightly smaller on the bleed nipple side and although it looks the same to the eye the pipes simply will NOT go into the inner hole on the opposite side of the calliper - not even close, and we checked both callipers too. So we reversed direction and cleaned the faces a bit more and reinstalled them on their original sides, and both lined up perfectly square with the disc, with the rest of the brake job uneventful.

I'm not sure that they're fully bedded in yet, they are working ok but I wouldn't say that they're as sensitive as they were before, but I think it's still wearing through the protective coating on the disc (some sort of aluminium paint ?) so I'm sure it will sort itself out in time, certainly in time for the MOT, and no more scraping or squeaking.

Satisfied with a job well done and a break for some food we then tackled the timing belt inspection. David Hallworth kindly loaned me his timing tool kit for the ES9J4 so we had all the right bits and bobs at hand.

Stripping down the side of the engine and getting the covers off was fairly uneventful and apart from a couple of hard to find timing cover bolts it wasn't as difficult as we anticipated. In the process we confirmed that the roller for the aux belt tensioner is pretty dry and rough so needs replacing soon. (Can the roller be replaced separately to the tensioner ? It looks the same as the standalone roller just below it which needs replacing too, although it isn't nearly as bad)

We got the covers off and initial inspection of the belt looked good, although at first I thought it was a bit loose, but it later didn't prove to be the case after manually turning the engine over to line up the timing pegs, with the tension seeming pretty normal using the rule of thumb twist method - from memory it was a slightly more than 45 degrees on the drive (front) side of the crank pulley. It certainly didn't seem floppy, nor over tight.

There are no cracks or frayed cords on either flat or toothed side of the belt anywhere we could see, it looks like its only a few years old. As Richard said there were fresh tipex marks on the belt and some of the cam pulleys, so together with the spotless condition of the belt we're pretty certain that someone has replaced the belt.

When we checked the timing we found it very close - certainly not the large error I was hoping for. Only one cam would immediately peg up, the other three were out slightly, two of them I would judge were between 1/4 and 1/2 of a peg diameter out, so maybe about 3-4 degrees or so.

In fact the front exhaust cam has the adjustment bolts hard up against one end of the slot and it only JUST reaches so that the peg will go in, so clearly the belt should have been re-timed on that cam. The others had a small amount of adjustment left but were all very close to the (same) end of the slot. So whoever fitted that belt didn't follow the factory advice that says to make sure its near the middle of the slot after tensioning if not re-time the belt on the cam...maybe it was done on a Friday afternoon.

Here are some pictures:













Interesting thing is the front exhaust cam had a tipex mark between the inner and outer cam wheels as well, while the others had tipex marks at the outer edge of the cam wheel and on the belt. (Not visible in these photos but at different rotations the marks on the belt were clearly visible)

So it seems that someone has maybe timed this belt by counting teeth and marking the cam wheels rather than pegging it...

There is evidence of a small amount of coolant leakage from the water pump (a bit of white corrosion visible in the photos) but nothing significant. We couldn't' check the rollers for play while they're under tension but we did run the engine with the axillary belt removed and found that some of the rollers are somewhat noisy, so they'll need doing at some point and clearly weren't done with the belt.

We tweaked the timing of the three cams that weren't quite right, got it spot on and put it back together again a little bit deflated that the large timing error I was hoping to see just wasn't there. On the plus side while the rollers are a bit noisy the belt is in good condition and seems to have been replaced, the timing is (and was) correct, tension seems ok, there aren't any oil or coolant leaks onto the belt etc, so a timing belt change is not imminently urgent, (eg, is now post MOT) unfortunately nor will a timing belt solve the problems I'm having.

On trying to lower the car back down again the drivers front jacking sill decided to collapse on us, and there is now a hole through the sill that most likely won't pass an MOT without welding...





So now I need to figure out what to do about that. Doh!

So there we are - the mystery still remains unsolved. I do have a couple more ideas now that I've seen the camshaft timing is correct, so I'll post those in a later message after I've had time to think about them a bit more.

[lexi]

It is amazing how solid stuff looks with factory stonechip, yet inside is different story.
You will not know what you are up against till it is cut out. It is where you can stop till you get solid metal. I think all Xantias have that now, lurking, unless they have been treated inside from newish.

When is Mot?

[RichardW]

You're a light weight.... I was up at 7 (lie in for the weekend, when small children always seem to want to get up early!), took the boys and bikes to Helix park at Falkirk, saw the Kelpies, then we ended up on the other side of the canal, and rode all the way up to Falkirk Wheel and back. I was towing Toby in the trailer, which makes it hard going! About 15 miles in all - first time I have ridden my bike in about 10 months...now my backside is sore!!

Re the sill - sure I can weld that, will PM you.

Given that the symptoms seemingly fit a valve timing problem - what about a worn cam (or cams), given the apparent patchy history of oil changes....??