Conference terri::cars_uk

IMHO.
	I wouldn't even care to try fixing a diesel!  One of the reasons why 
petrol LandRovers are specified for remote desert work is because the Diesel 
versions require such specialised knowledge.

	I realise that this isn't necessarily so to remove and refit a 
cylinder head, but bearing in mind the higher compression ratio (23:1 in the 
XUD engine) the work involved is all to very much tighter tolerances than the
petrol version.

	I have a Citr�en BX TZD, but I'd rather suffer the financial penalty of
putting the car into a garage myself, even though I've changed MANY a head 
gasket on petrol engines and done complete strip and rebuilds too.

				Malcolm.

    Sounds like a valve guide oil seal or a worn guide to me. When the
    engine is standing any oil in the cam/tappet cover will tend to run
    down the shaft of the valve and into the bore. As this only happens on
    start up I would guess that it is an exhaust valve because when this oil 
    has burnt the compresion pressures will ensure no more oil finds its way 
    down the engine. If it was an inlet valve the vacuum will draw oil into
    the bore.
    
    Hope this helps
    
    Simon

    I assisted with the removal and replacement of a Golf diesel cylinder
    head to fit a new gasket. This was an overhead cam engine, and appart
    from locking the cam, getting new cylinder head bolts, (can only use
    the bolts once), and the phenominal torque the heads bolts are tightened to
    it s a fairly straight forward exercise. Also the sequence of the head
    tightening is quite awsome. What it amounts to is to tighten the bolts
    up to the required torque in stages, then when warm turn each bolt
    through 180 degrees. I don't know what the torque was but it required a
    two foot lever on the socket bar.... Its not nice... The general
    thought was that the bolts are actually stretched to ensure the correct
    head loading. So if you are brave enough to tackle such a job make sure
    you have.
     
    	1)the correct type of socket head  (torq-X?)
    	2)suitable torque wrench
    	3)either a Jeff Capes on a 1' tommy bar, or long tommy bar suitable
    	for Joe Public
    	4)new head bolts (expensive)
    	5)plenty of time
    	6)workshop manual (this is a must)
                    

	I'm rapidly going off the idea of taking cylinder head off!

	I was going to check the valve clearances, since a valve which didn't
	have any clearance could cause the problem ( or so I was thinking ).

	Discovered the inlet valve clearance is 0.0006 +/- 0.0003 inch.

	Since my feeler gauges give up at 0.0015 I don't think I'll get
	very far.  I also don't see how an amateur mechanic can cope with
	clearances like 0.6thou!

	From the previous replies I think I need a new head - especially as I
	now think I have two problems:

	1) startup smoke - diesel unburnt - caused by sticking valve (or so
	   the diagnostics engineers say) - until car has warmed up a bit.

	2) worn inlet valve guide and/or inlet valve oil seal and/or exhaust
	   same.  I think this because I do get a little smoke at times which
	   looks more like oil than diesel sourced when I put the car under
	   load.

	All adds up to a new head I think.

	Now, since I don't want to take the head off myself ( well actually,
	its the putting it back on that bothers me ) anyone got any good ideas?

	Exchange and Mart advertise heads and/or getting the head
	reconditioned which is cheaper but takes longer.

	What I really want now is someone near Reading that can do the job
	without me paying Citroen dealer prices.  Any suggestions?	
	
	(I'll also get the cam belt changed while I'm at it)	

	Regards

Tony

    
    Is the car difficult to start?
    
    My brother had a diesel van which was a pain to start. When it did
    eventually start it would smoke like a chimney until it was properly
    warmed up, (the smoke was white btw).
    
    Anyway, it turned out to be flakey 'glow plugs' or whatever they're
    called. These were replaced and the thing started like a dream and the
    white smoke disappeared as well.
    
    Just a thought!
    
    Cheers,
    
    Dave.
    

-0.1

The glow plugs have been checked during diesel diagnostic session, and are
declared ok.  The smoke is white at  startup - but caused by one cylinder
not burning any fuel - due to no compression when cold.

Cheers

Tony

I'm not much of an expert on these things, but I was wondering 
why your compression was so low when cold.  What is it when 
warm?  Is it like the rest of the cylinders?  Generally a sticking
valve will not cause smoke.  If the guides are worn it would tend to
blow smoke all the time (but more when cold).  It sounds like 
something more serious than a stuck valve.

Jeff

>I'm not much of an expert on these things, but I was wondering 
>why your compression was so low when cold.  What is it when 
>warm?  Is it like the rest of the cylinders?  Generally a sticking
>valve will not cause smoke.  If the guides are worn it would tend to
>blow smoke all the time (but more when cold).  It sounds like 
>something more serious than a stuck valve.
>
>Jeff

Interesting question re: what is the pressure when warm;  Don't know. I've been
advised the pressure is 20 PSI when cold, and then when warm pressure is OK.
The performance of the car would indicate that it is running on 4 cylinders
when warm - and when cold you can hear the missing cylinder is not firing.

According to the diagnostics people it is not unusual for a valve to stick
when engine is cold, but they aren't very forthcoming as to possible causes.

The smoke at startup is white which indicates unburnt Diesel rather than Oil.
If it was just valve guides then I would expect more of a blue tint to the
smoke. 

/Tony

    I had the BX19 TGD on the car scheme, and it used to burn oil and smoke 
    when starting from cold.
    What sort of mileage has your motor done?
    
    Tim

Ref -0.1

	Car has done 123000 miles.

	Actually - the smoke in the morning seems to have reduced a bit!
	Wonder what has caused that to occur?

/Tony