Xantia-Cylinder Head Examination

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NewcastleFalcon
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Xantia-Cylinder Head Examination

Post by NewcastleFalcon »

Pretty much a continuation of the aftermath of the camshaft breaking as described in "Crankshaft pulley bolt 1 Newcastle Falcon 0"

The score remains the same on that topic, and it will resurface but currently I have the cylinder head off and am assessing what needs to be done to get the motor working again. There have been some excellent contibutions on the previous thread but I would like to draw on the assembled knowledge of forum members in relation to a camshaft only renewal.

My initial assessment of the head is that it is in good condition with 7 of the 8 valves working normally with the 8th bent. If I can get away with replacing this valve and a camshaft plus caps only replacement I will. Some say the line boring is essential-clearly beyond my capabilities. Don't the performance enhancement brigade install different camshafts in various engines and make them work?

One useful tip I discovered from youtube was how to dismantle valves without the use of a valve compressor.

It is basically a normal socket of the right size to press down on the valve spring ( I pushed down on a lump hammer pressing on the top of the socket to compress the spring. The bit of magic is a small magnet attached to a stub of ballpoint pen resting in the socket hole. When you press down on the socket the collets are sucked up by the magnet and hey presto, job done!

here is the link it is entitled "How to remove/install valves with household tools" if the link fails


http://www.youtube.com/watch?v=es6raocA ... re=related
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Post by RichardW »

It's not the camshaft you need to worry about - it's the caps. They fit the caps then bore out for the bearings - which means that if you fit a new set of caps they will not necessarily line up with bottom parts of the bearings, which will make the cam shaft tight and liable to seizure. If you can get a selection of caps you might find some that are a good fit, and a bit of judicious use of emery paper might get enough clearance for the cam to run. Or it might just seize first time it gets hot.... :cry:
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Post by NewcastleFalcon »

Are the "bottom parts of the bearings" the three machined "semi-circles" (for want of a better description) which appear integral with the head.

Must admit the camshaft just came off in its 3 or 4 bits, together with the broken caps and I didn't even look to see if there was a separate "bottom bearing" which may normally lie in the machined semi circles in the head. Maybe you can put me right on this.

One time I did get a new camshaft installed on a ford sierra diesel head, and utilised caps from a second hand source. Not sure but I think they drilled the holes in the caps where the studs from the head poke through to give them a little extra room, and fitted new shell bearings. I think the ford had bearings top and bottom.

thanks Neil
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Post by RichardW »

I wasn't sure if there were separate shells, hence my vauge statement..... :oops: Anyway looked in the diesel engine book, and it does appear that that there are no shells, the shaft just runs direct in the head / caps. Hence any misalignment between the head and caps will lead to an undersized bearing and hence possible cam shaft running problems.
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Post by Old-Guy »

The reasons why engine (or cylinder head) manufacturers fit bearing caps before machining the assembly is two fold:

- it's one easy operation to machine a round hole really accurately instead of two difficult operations to machine two semi-circles to twice the accuracy.

- the positional tolerance on machining the mating faces can be quite generous without affecting either bearing size or alignment (a lot less scrap).

But modern machining centres produce parts at high speed with amazing accuracy. If you could find a spare set of caps, I suspect that the chances are that they would fit without any problem. But, as you have experienced the most common type of damage to a head, are you likely to find a spare set of caps?

If you do find a set of caps you'll need to check the new camshaft with the valves removed - it must turn freely but without detectable play. You'll probably need to fit a (new) guide for the bent valve.
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Post by NewcastleFalcon »

Thanks for the replies:

Its a while since I had a wander around the scrapyards, but I will give it a go and see if there is a Xantia 1.9TD lying around from which I can extract both the caps and the camshaft itself. I think its worth a look as a means of resurrecting the motor and the car at least cost.

The engine no is CU9M6038511

Could I widen my search to Peugeot (is that how you spell it?) 1.9 diesels of a similar vintage?

I punched the bent valve out through the valve guide, other valves using the same guide slide in an out freely. Replacing the valve guide doesn't sound like a job for the black and decker, so if a replacement valve slides freely in an out and seats properly hopefully I will not have to get this done.

Thanks Neil
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Post by citronut »

dont you have an auto enginer near were you live, as it would be better to get the other valves checked, also the valve guid replaced as it will almost certainly be cracked,

you might also ask the enginer if they can check/line bore the cam bearings with the replacement caps in situ just to be on the safe side,

regards malcolm
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Post by h2ocooler »

If you can find a donor engine for the cam and caps just get the whole head instead, will be far less faffing about in the long run trying to get the caps to fit and I think would work out cheaper.
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Post by NewcastleFalcon »

I am in the process of taking the head of my "spares" xantia 1.9TD, to fix the other one, but still amusing myself in ressurecting the good condition but currently dead head with a valve replacement and replacement camshaft and caps.

I also had a quick look around one scrapyard and found a white "R-reg" Xantia Diesel SX with a clean looking engine and a clock at 125000miles ish. I should have looked closer, but I think it was a 1.9TD.

There was some extra bits at the flywheel end of the camshaft/rockercover/head compared to my M reg 1.9TD and the "L-reg" one I use for spares which at that end of the camshaft just has straightforward end cap for the camshaft which bolts into the side of the head with two bolts.
I think the additional metal appendage at the flywheel end of the camshaft on the R reg had hoses coming out of it.

Should have taken a picture, and apologies for the vagueness but any ideas just for academic interest what the aditional bits are?

I was quite enthused that the first scapyard I happened to look in at did have what appeared to be a suitable source for the camshaft and caps. It is much easier to take out the camshaft and caps that remove a head in the scrapyard environment. The scrapman reckoned on £40 as being the price for taking the camshaft.

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Post by dieseldoggy »

Hi the bits you found on wnd of head are on the later ones for emission system it's a vacuum pump for the EGR valve and cold start mech.your's will have a waxstat.
you can use either leave vac pump onit or remove and use blanking plate.

Anything that uses 1.9 XUD engine should be ok.not sure if SOHC petrol ones are the same cam caps as base circle and bearings might be diff?

If you want to check if the other valves are ok ie seating tight and not bent? turn head with valve heads up so combustion area is flat then gently pour some parafin into them and leave for a while to see if it leaks away ifso they will need doing
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Post by citronut »

dieseldoggy wrote
"If you want to check if the other valves are ok ie seating tight and not bent? turn head with valve heads up so combustion area is flat then gently pour some parafin into them and leave for a while to see if it leaks away ifso they will need doing"


this is easyest done with camshaft removerd, as all the valves will/should be closed,


regards malcolm
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Post by NewcastleFalcon »

My "L-Reg" 1.9TD also has a slightly different anatomy to the "M-Reg" one I have already taken the head off.

The "L-Reg" has clip on timing belt covers, and and a metal "engine front plate" or plates which I may have to remove to get the head off, and work out what other bits have to be undone to ahieve this.

I pinned the flywheel hole at TDC for the cylinder nearest the flywheel (no 1 i presume) but the hole in the camshaft sprocket is way off the hole in the head (i assume this to be the one at 4 oclock roughly). Engine fired up fine last time I did it and cambelt intact, in good nick, and on the sprockets. Camshaft and caps fine.

I should expect the camshaft sprocket hole, and injection pump sprocket holes to line up when the flywheel is pinned shouldn't I?

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Post by NewcastleFalcon »

The head is "nearly" off the "L-reg" spares Xantia. Embarrased to admiit but its been a full day job punctuated by dropped tools and persistant rain, and its not quite done yet. The job was much simpler on the M-reg.

I was hoping that I wouldn't have to take off the metal engine plate but it looks like the head is reluctant to pop off at the timing belt end, and I suspect that Haynes may not have been so inaccurate as I first thought.

The camshaft is off as is the camshaft pulley and the top one of the engine mounting bolts which appeared to screw into the head is also off.
The tensioner adjuster bolt has been removed and the tensioner pivot nut slackened. I have three engine mounting bolts as yet unattacked. The two bottom ones are the ones the "special tool" fits into, and the third appears to combine the function of providing a "head" for the upper cambelt covers to slip over as well as a bolt for the engine mounting.

Clearance between the engine and the bodywork of the car, allows you to get in a ring spanner at best although I did get a socket with my drain plug square ended adapter in to loosen the tensioner pivot nut.

Unless anyone knows different looks like removal of the engine mount in its entirity, the tensioner, and quite possibly the idler pulley just like Haynes says, may well be required just to get the metal engine plate out and free the head at the timing belt end.

Neil
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Post by Old-Guy »

Conventionally cylinders are numbered from the 'front', the camshaft drive end, of an engine - i.e. the opposite end to the flywheel. This is the case with the XUD engines and would explain your problem!

For engines of unconventional design it's wise to check with the manufacturer.
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Post by NewcastleFalcon »

Thanks for the reply.

By No 1 I probably meant No4-the cylinder nearest the flywheel.

Have I currently pinned the flywheel then on the top of the exhaust cycle for no 4 cylinder (both valves closed) and the timing holes in the camshaft and the injection pump would align with one full rotation of the flywheel which would ring cylinder No4 (nearest the flywheel) to the top of the compression stroke?

Neil
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