HG repair requirements

[MikeT]

Thanks for explaining those details Jim. I'm writing up my own instructions in preparation. Is it necessary to remove the cambelt etc before the manifolds? The former would mean the engine being tilted back, restricting access to the latter. Is it possible to force/wedge the engine forward or will I have to refit the top mount for this?

[CitroJim]

Hi Mike,

You will, after you've done the job, be able to write the difinitive guide

When you remove the cambelt is really not too critical. I cannot think it gets in the way but obviously has to come off at some point. It needs to be removed before the engine mount and the top tensioner comes off. As you are replacing it anyway, it is often just as easy to cut it off.

One tip I will give, in connection with teh cambelts, is to undo the crank bolt as one of the very first jobs you do. Do it with the engine warm and do it whilst you can still easily bring the starter motor into use if you need to in order to shift the bolt.

[MikeT]

Thanks Jim, I jacked the car to begin the work today but an underside visual inspection has got the alarm bells ringing. It's so wet underneath I've spent my time trying to find out why and think it may be leaking from the head gasket.

Although I can't see very well, I have seen oil (or is it diesel?) covering just about everything within the vicinity of the head/block mating surfaces at the rear of the engine and below. The worst of it seems to be where the air inlet pipes and fuel return hose is but access is too limited to see further.

If anyone has any hints, tips or advice for making a better determination I'd appreciate it.

[CitroJim]

Looking at the pictures in your blog thread Mike, the oil around the turbo is nothing much to get excited about. Most are damp there and the oil is normally just oil condensate from the crankcase breather. You'll likely find the jubilee clip a bit loose.

Heads do leak oil sometimes when they go and a new gasket will fix it. Remember, oil is supplied to the cam gallery in the head at full pressure and it does not take much of a gasket weakness to make it weep.

Most Xantias of a certain age look pretty oily around the front subframe from years of little LHM weeps and so on. You try doing an LHM change without spilling any LHM when removing the tank and pulling out the filter head and you're doing well. It all adds up. As long as it's not dripping, nothing to worry about

[MikeT]

Assuming the head gasket is leaking the oil to atmosphere as well as the combustion gases into the coolant - would that indicate or vindicate to any degree the head being warped/cracked/corroded?

[CitroJim]

Assuming the head gasket is leaking the oil to atmosphere as well as the combustion gases into the coolant - would that indicate or vindicate to any degree the head being warped/cracked/corroded?

Lacking in any psychic ability Mike, I cannot answer that one

Only by having the head off will you know the full SP. I'd say it was all part and parcel of a failing gasket. As you've said earlier, Off with the head! You have nothing to loose...

[MikeT]

You're not? Have you got an Xray machine I could borrow then, Jim?

Going through a mental dry-run of the job I fail to imagine what the EGR looks like now. I thought it was just that domed saucer device but Haynes says it is two valves that must be removed as one assembly. Anyone got any pictures as I couldn't locate the bolts feeling around it?

On the subject of working blind, is it easy to locate and undo the manifold bolts? I'm especially thinking of the ability to swing a long lever particularly when it comes to torque setting.

Should I remove the exhaust manifold from the turbo and exhaust or leave it on, as described in Haynes, requiring the removal of the studs? What are the disadvantages?

[CitroJim]

The EGR valve looks like a little lantern sat on top of the exhaust manifold; in fact when you see it you'd expect to find a little candle in it

It can stay attached to the exhaust manifold; just unclip it's concertina pipe from the inlet manifold spigot, remove the inlet manifold and then clip the other end of the concertina pipe off the EGR valve.

It's a moot point about the exhaust manifold, whether or not to leave it on the head and disconnect the exhaust downpipe or unbolt it from the head. I don't know for sure if the head, manifold and turbo will come off in one lump as I've never tried. In any case it'll be a heavy old lump to lift.

Basically, if you plump to leave the manifold in-situ, it helps to remove the manifold studs. If you're lucky, some will come out as you undo the nuts. Those that remain in the head are best removed using the "two nuts" method. That's one nut locked against another that allows the stud to be removed. There is no room down there to use a stud extractor but using the two nuts method is not difficult. You'll hopefully not find any studs badly corroded or seized as is so often the case with a petrol engine; diesels run cooler around the exhaust manifold.

As I've said before, it helps to have little girly hands and a wide selection of different shapes of ring spanners. That little "Lazy C" spanner I've spoken of in the past is a handy little thing, as is a 13mm ratchet spanner if it has a reasonably small head.

When you do remove the manifolds, take note of where the spacers go and where each length of stud goes in the head. Some studs are long and used with long spacers and other are short and not used with spacers.

[MikeT]

Rain stops play.

According to Haynes, you have to remove the EGR before removing the manifold bolts but I think I will prefer your method to leave it attached if that is possible.

Haynes also gives the impression that I can remove the exhaust manifold studs and leave it connected to the turbo/downpipe, as you say. The only other option it says is to remove the turbo first which looks extrememly difficult as far as the inlet/intercooler pipes are concerned.

[CitroJim]

According to Haynes, you have to remove the EGR before removing the manifold bolts but I think I will prefer your method to leave it attached if that is possible..

Take it from one who has done the job Mike. No need to remove the EGR valve from the manifold. You can work around it, as you can the turbo. One nut near the turbo is a puzzle but the secret is to loosen it as much as you can and then, when you're ready, pull the mainifold back whilst still loosening the difficult one. Eventually, the manifiold will move back sufficiently far to slip the nut off. It's all a bit Krypton Factor but it can be done.

Have a trolley jack under the exhaust downpipe to support the mainifold/turbo assembly and all will be fine.

Another little tip: The bolt on the inlet manifold that the BoL tels you not to remove (the one in the centre between cyliners 2 and 3). Do the opposite and remove it. It'll make life easier.

[MikeT]

Whilst there is no apparant need to remove the cam cover when removing the head you'll find you'll need to in order to remove/refit the inlet manifold.

Another omission from Haynes then.

Haynes also says to remove the camshaft sprocket but I fail to imagine why this is necessary and doesn't that make the timing locking bolts redundant? Additionally, if the piston crowns need cleaning and I have to rotate the crank... I'm lost

[CitroJim]

[Another omission from Haynes then.

They don't call it the BoL for nothing you know

One good reason for removing the cam sprocket is that it has incredibly sharp edges on it and will rip your hands to shreds How do I know

You'll loose cam timing anyway Mike, when you prepare the head for skimming. It's a walk in the park to restore the cam timing

[steelcityuk]

Hi Mike,

When I did the head on my 2.5TD XM I found it useful to keep my camera phone in my pocket. I took photos throughout and posted them on Flickr so they didn't take any looking after.

There's some here if your interested showing various stages of progress on the head, turbo, etc. -

http://www.flickr.com/photos/7328220@N02/page3/

I found a large number of clean jam jars and a marker pen useful to keep item's clean and safe. A cheap ultrasonic cleaner is very useful too.

Steve.

[MikeT]

If re-timing is easy, that's good news though does it mean I've just wasted 24p buying three 8MM bolts? Cheers Jim.

Thanks Steve, I would be most interested in seeing those pictures but all I got from your link was "steelcityuk doesn't have anything available to you." Why me, I thought we'd settled our differences?

I do plan on setting the digicam on a tripod and video'ing my progress. That way I won't get the cam so oily taling lots of individual pictures and I can also dictate notes while it's recording. Then, come the evening, I can review it all on the pc and make notes for re-assembly. As Jim says, there's nothing worse than not knowing which part goes where - especially on an engine that already has nuts and bolts missing and wires/cables routed differently

[head-mechanics.co.uk]

well mike i have read your questions and seen the replies and i dont think i can offer anymore advice than what you have been given. the key to a good head repair is CLEAN surfaces. skim and pressure test is a must. The skim will change the compression ratio but this wont be noticed. if you skim to far the valves will touch the pistons and this is usually what actually causes the misfire or stalling of a engine. cam followers must be drained. and the timing cant if i remeber be done wrong. there are slots in the camsprocket, flywheel and injection pump.? A gasket from payen will be as good as any. if the job is done correctly you wont notice any difference from the gasket. nevlock or places like it are great places for engine components. i would advice against GSF as they are at times rip off merchants. i would defianletly change the water pump and camblet you would be stupid not to. Piston/valve polishing isnt really needed unless the pistons are thickly coated. a good brake cleaner will be good enough. take you time is the key. photos and a note book if your not sure.

also think there head bolts and not stretch bolts but i cant remeber you guys are the citroen masters been a while since i done one. but my dispatch is head bolts.

ALL THE BEST.
if you need any help just email.