BXProject

[Philhod]

You've reminded me now you mentioned torquing down the injectors.

Before I fitted the new head (gratis from Doc) I was having smokey starts. I removed the injectors, cleaned them out but fitted new copper fire washers before torquing them down.

No more smoke ....at all !!

[Bx Bandit]

It's always good to make sure they're tight in the head, but I meant from when I stripped the injectors down to clean them up (but they were perfectly clean anyway ) so I whammed them back together.

One appeared to be leaking so I had to whip it out and tighten it up in the vice (and then some!) but I later realised I'd not torqued them up proper, so pressure wise they were probably all over the shop!

[jonathan_dyane]

Get your timing sorted first mate, really do. You kicked out a lot of black stuff when you left off at Vannys which means you're over fuelling a lot which ain't gonna help your starting issues either.

Surely over-fuelling will help starting rather than hinder? I'm thinking of my tractor, no glowplugs and ancient in-line injector pump, on which to aid cold starting there is an 'excess fuel button' which when pressed basically massively overfuels the engine causing it (when it eventually fires) to scream into life with clouds and clouds of black smoke.

Agree completely on the timing front however.

[Philhod]

Lot of old tractor motors exploded using those things. They injected that much fuel if it didn't start at least second time you got a hydraulic lock.

The black clouds are unburned fuel that just about makes it to a gas, in the exhaust!!

[mat_the_cat]

I fitted the Xantia plugs which as I understand are more robust as they are designed to be running for a period while the engine warms up. This may be my (lack of!) understanding, but I didn't think a diesel engine could be overfuelling at idle, as the engine speed is purely governed by the amount of fuel injected. I can understand it in Jonathan's example, as you are injecting more fuel than idle speed requires hence when it does fire it revs up above idle speed.
Mine does not start with more revs than idle, so I think that when I'm starting it, the amount of fuel isn't the problem. Agreed that there is a lot of fuel passing through when booting it though....
The fuel delivery curve isn't quite right, obviously, but if I regulate the throttle position to match the revs/boost level the smoke is not visible from the driver's seat. I can't seem to reduce the fuelling whilst still keeping the power level the same. Hopefully will have a play this weekend, I've spent most of tonight trying to get an old generator to run. Managed it in the end after I had unblocked the main jet in the carb, seems like it had got gunged up after about 10 years of not being run.

[docchevron132]

Ahh see, then we get into the realms of matching the turbo to the pump, or rather matching the fuelling at any given time to the amount of boost neing offered by the turbo.
Certainly your on boost fuelling is WAY too high, and wont give an extra power, it just wastes fuel.
I mean, mine smokes like a fucking chimney, but yours, jesus christ, when you booted it off downt he road I could hear the fuel tank emptying!

With power increases it's always best to do small little adjustments at a time, rather than wind everything out as far as it can go and hope the engine doesn't shit itself out!

[Bx Bandit]

Get your timing sorted first mate, really do. You kicked out a lot of black stuff when you left off at Vannys which means you're over fuelling a lot which ain't gonna help your starting issues either.

Surely over-fuelling will help starting rather than hinder? I'm thinking of my tractor, no glowplugs and ancient in-line injector pump, on which to aid cold starting there is an 'excess fuel button' which when pressed basically massively overfuels the engine causing it (when it eventually fires) to scream into life with clouds and clouds of black smoke.

I had to think a bit about this as I quite often extrapolate how things work in my head and then stumble, but here's my logic.

The pump automatically makes the maximum amount of fuel available for starting ('auto excess fuel button'!!!) but within the parameters/adjustments it is set to. With the max fuel screw wound in, the pump makes more available. I assume there must be a point where you can put too much fuel in, making an already difficult process (starting cold diesel) more difficult.

I also draw that logic from putting the 1.9 pump on the 1.7 - starting became a lot more smokey and lumpy with the same glow plugs and glow plug relay.

There are lots of settings on the pump to be played with and to an extent they interact and it can be hard to know what's what. If I were in your shoes Matt and without a dial guage, this is what I'd do.

1) Mark where your timing is now!
2) As if you were doing a timing belt, get the engine to TDC. Your pump should be timed at 0 deg at TDC. This makes it easier to time with out a dial guage.
3) Where the 4 high pressure pipes leave the pump, there is an access plug in the middle. Undo this. Fuel will leak out.
4) You need a clean philips screw driver. Make there are no sharp edges on it. Place it in in the hole left by the access plug.
5) Now transform yourself into Mr Tickle and gently rotate the engine back and forth either side of TDC. You should feel the screwdriver sliding in and out of the pump (ooooh errr!) At TDC, your screw driver should be pushed out the most.
6) If it isn't, Undo the nuts securing the pump to the housing.
7) Lock the engine in TDC on the flywheel and rotate the pump until the screw driver is sticking out most (in fact, it may be easier to leave out step 5 and go straight to step 6)
Once you are happy you're as close to this as you can get, then put it all back together, remove the locking pin on the flywheel and hey presto! See how she runs after that. Then you can start to fiddle with the other settings.

[Philhod]

Very well explained there Bandito.

If you can get a second pair of hands to rotate the pump....I use a piece of stainless rod and a 6" rule against the body, to measure the stand out.

The Diesel testing station I mentioned earlier, does this and all the other piston settings inside as well. Locally I was given an estimate of £40 inc vat to do this, plus any new seals needed.

[mat_the_cat]

Thanks for the explanation Mr. Bandit! I *may* be slightly fucked as I am reading this, in conjunction with the BOL, but it mentions a figure of 0.66mm on the DTI or 12.5°....are you reckoning that as mine may well be so far out that simply setting it to 0° is likely to be an improvement? Or am I missing something?
Right, I'm off to hit the sack. I may well go to bed at some point too.

[Bx Bandit]

Which version of the BOL are you reading? I thought that all later BX and therefore assumed that all Xantia's would be timed at 0 deg. i.e. no degree off set, no 0.6mm on the dti. They simply moved the slot in the hp delivery shaft thingy to compensate. I'll have a check to make sure mate.

[mat_the_cat]

It's the one for the Xantia, dated 1999. I do have a DTI now, just need something to mount it on the pump.

[Philhod]

mag base required

[mat_the_cat]

Hmmm, as mentioned elsewhere I still haven't touched the pump, but I am thinking about something Bandit said earlier in the thread. Glowplugs. Especially as the weather has turned that little bit colder,a nd now it needs a couple of goes with the plugs to get in going after say 5 seconds cranking. Gut feeling is something has got worse.
I know speculation isn't going to solve anything, but does this theory make sense? Chris, you reckoned that it sounded advanced, right? And diesels seem to knock more when they're cold - is that purely down to the fact that they usually (always?) have some sort of timing advance? Or is it due to the way the fuel is igniting with a cold engine that makes it sound...erm...knockier?
If it is the latter, and I have some problem with the glowplugs or module, then could that account for the diesel knock being more pronounced when you heard it at Vannys? 'Cos the engine is fine when warm, wouldn't the knock be also noticeable when warm if the timing was out? (I know I do really need to check it, I'm just bouncing ideas around so I understand more). I think it goes pretty well when warm although I will concede that the pump isn't set up optimally. At least not where economy is concerned. That said, the economy didn't noticeably drop off when I upped the boost/fuelling...

[Philhod]

The XUD is an indirect injection system. Although they generally run much quieter than direct systems,
yes they do make as much noise, if not more when first starting, although this fades quite quickly.
They also smoke (blue) as well and it smells paraffiny, but these traits last only for a few minutes, dependent on the age/condition of the engine.
So all that points to the fact that you seem to have timing/ fueling problems.
A fairly cheap job would be to fit new Bosch glowers and another timer relay and see if it makes any improvement.
That said I still think you need to get the pump settings checked first as your just whistling in the dark unless you have a known starting point, and you never know all may be good.

[mat_the_cat]

Agreed Phil. There's so many unknowns that checking the pump timing would at least eliminate one. I don't really suspect the plugs, as I changed them about a year ago (to Bosch ones ) and the problem remained the same. But simply being new doesn't always mean they work...I've been down that road before and the only component I didn't check was the brand new set of HT leads (on a different vehicle). Turned out to be the king lead failing after a few weeks!
I know where there is a Xantia sitting in a quarry, so I could pinch the module off that.

[docchevron132]

Erm, the more pronounced knock when cold is down to several factors really, one being the amount of heat int he combustion chamber, one being the timing, another being the amount of diesel injected on each stroke, another being compression, many many variables really.

In your case, from what I heard that morning it sounded massively advanced as opposed to over fuelled, equally though there was A LOT of unburnt diesel int he exhaust which indicates a lack of a good full burn.
Some of this may be down to the pump over fuelling, some may be down to the timing, some may be down to the glow plugs.
But as Phil says, until you have known parameters to start from it's all a bit shooting at shit in the dark really.
When you took off down the road the amount of over fuelling became obvious, it was horrifick! I thought mine smoked a lot, but fuck me yours must be solely responsible for GW!
But that of course is on boost fuelling as opposed to base fuelling, which is linked but two seperate things.
Hence it all gets a bit complicated if you still dont know where you're starting from in the first place!

[Bx Bandit]

And diesels seem to knock more when they're cold - is that purely down to the fact that they usually (always?) have some sort of timing advance?

The earlier (than yours or mine) versions of Bosch pumps had timing advance devices, to give the fuel that little bit longer to ignite. But, with the development of glow plugs that don't self destruct if left on for more than 15 seconds, things changed. So instead of a timing advance, the relay kept the glow plugs on for up to 3 minutes after starting.

So, to answer your question mate, the later style glowplugs and relay will help your starting, but you'll still have timing issues. I have a mag base which you can use. Either that or fit a knock sensor!

[mat_the_cat]

FUCKING YESSSSSSSSSSS!

It works!

Finally I've got round to checking something rather than procrastinating and I think I've found the problem. I ran a jump lead from the battery to the glowplugs to keep them on once the engine fired, cranking it after the normal 10 seconds or so. It started and ran perfectly (at least to my untrained ears) with no smoke. Now I'm not saying the timing is A1, but it doesn't display any of the symptoms it has done for the last year or so.
So it looks as though perhaps the main problem was the fact (like /\WHS) the pump was setup up for glow plugs that would be on for 3 minutes or so after starting, wheras the BX relay turned them off (I already have the later plugs). Maybe that was exaggerated by other problems, but it feels like I've made a step forward. Thanks to all for the ideas and advice.
Does the Xantia module fit fairly simply (i.e. a drop in replacement)?

[Vanny]

non straight drop in (different plug) but simple cut and paste

[Philhod]

congrats, a nice easy fix then for once.