XANTIA HDi RUNNING ROUGH

[moizeau]

Before you remove any valves, turn the head upside down and fill the combustion chambers with diesel or heating fuel and leave over night. See if they are all the same height in the morning.

[Skull]

moizeau Cheers, I've already got them soaking in water .... there's no combustion well to speak of except the valve seat gap ...

Skull's - Valves soaking

[moizeau]

The only problem with that is that water will not pass through a gap of, I think, 1mm without pressure whereas diesl is a seeking agent and will

[Skull]

Ah right I’ve got some diesel …the Mrs will love that in her utility room ….

[mickthemaverick]

Still sticking with my initial proposition (see way back in the thread), faulty inlet valve spring not holding the valve shut!!

[CitroJim]

....

That coolant passage blockage looks significant and may answer a lot of questions. The blockage occurred, pressure built and that blew out the core plug.....

Sorry .....False alarm Jim ....That Coolant Port for whatever reason isn't actually cut out of the gasket ....whilst there is fine orange silt in the coolant I drained, corrosion seems to be minimal.

Now that's a good false alarm Gary!!! And it was a good theory whilst it lasted!

Means the head is very likely to be good to go again with just a light skim and attention to the valves... Be worth checking it for cracks though as one in the vicinity of the valve seats or a crack between valves may be the cause...

[Rhothgar]

Only just caught up on this since before Xmas.

Happy New Year to you skull (et al)!

Without going back through, didn't I at one stage question whether part of the broken cam follower may have been preventing a valve from closing fully? I'm sorry if not. Is it even the same cylinder?

I think ekjdm14 suggested replacing the cam follower first and then I backed that up and said get a small mini grabber to replace the lost mirror part.

I think your curiosity got the better of you. In temperatures like this, I really wouldn't have the interest in doing more work than is necessary but at least it has 100% ruled out the holed piston worry and probably some other worries.

Don't forget to make a note or take a photo of your head gasket and the number of notches it has as this will be important in ensuring the correct selection of the new gasket thickness.

Anyway, it's still a positive step forward and luckily you have no immediate need for the car.

Personally, I would just get a engineer to do an inspection on the head for flatness and perhaps crack testing.

EDIT: I see Jim has already suggested crack testing in post right before mine. I hadn't seen that before. Cracks between valve ports at the valve head used to be a real problem on the old BX diesel engines and I once had a repair done to one of mine. Not sure about these later engines but it's worth ruling out for sure.

[Skull]

Hi Rothgear - the head is off and awaiting cleaning, got the valves out eventually, there doesn't appear to be anything visually wrong so I'm going to do a clean up/de-coke and re-assemble, my gasket is a 2 notch (1.35mm thickness).

The mirror falling off was a dumb move - there was no way it was going to come out of the hole it went in and meant the head needed to come off

I'm not planing on engineers but I'll know more once the head and block are prepped....

[Rhothgar]

Hi Rothgear - the head is off and awaiting cleaning, got the valves out eventually, there doesn't appear to be anything visually wrong so I'm going to do a clean up/de-coke and re-assemble, my gasket is a 2 notch (1.35mm thickness).

The mirror falling off was a dumb move - there was no way it was going to come out of the hole it went in and meant the head needed to come off

I'm not planing on engineers but I'll know more once the head and block are prepped....

Yes I read you were thinking of an exchange.

I've got a really good engineer guy down here who is extremely reasonable so I am fortunate. I think it cost me £40 to have the head skimmed. It was ridiculously cheap. Really down to earth bloke that does a lot of work for farmers locally and has a great workshop in a garage at his house. Pretty big setup though.

An exchange seems a lot of money for what it is to me but if that comes with valves and cam and everything then it's definitely worth doing unless you want to lap your own valves in etceteras.

It sounds as though you have the necessary skills to do the work yourself so I guess it's a case of whether you want to do it.

[Skull]

It sounds as though you have the necessary skills to do the work yourself so I guess it's a case of whether you want to do it.

Yes I have fair DIY skills but haven't done a de-coke for 40 years

Valves removed and I also managed to remove the long Exhaust bolt threads from the block with the double nut and a hammer on the spanner, there was no room to do that in situ so that should make the head easier to go back on squarely.

I only looked at the prices of a recon head as I was expecting some damage somewhere but apart from the broken follower and the resulting tiny dink in the camshaft, all seems good

Skull's - HDi head with valves removed

I've been busy cleaning ....

Inlet valves seem the worst for build up but still not bad for the mileage @168K (last 45K on Supermarket grade diesel)

Skull's - HDi Inlet Valve

....and then more cleaning ...

Skull's - HDi Inlet Valve lightly cleaned

Job delayed slightly - My old hand valve lapping tool has done a runner so I've invested £9 into a drill attachment that will hopefully speed up the job when it arrives....I've still got the engine block and pistons to do while I wait for the tool ...ohh more cleaning

Once Valves are lapped and new Valve Stem Oil Seals are fitted assembly will begin ....

[moizeau]

Did you note which cylinders each pair of valves came from?
Also, while they're out it would be worth checking they are straight, dti them on v blocks (or v blocks made from lego). Especially the one from the damaged follower. There is also a 'wobble test' that although isn't fantastic, gives you an idea of valve guide wear.
I can't give you specs for PSA but can for a big old kwak which would be in the right ballpark.

[Stickyfinger]

Put the valves in a drill and spin them......you will notice any slight bend that way

[Skull]

Did you note which cylinders each pair of valves came from?

At great expense I have them numbered in an egg box

Put the valves in a drill and spin them......you will notice any slight bend that way

Yeah that's about my technical limit

To be fair I'm pretty sure they are in 'spec' as they made a lovely 'plonk' noise once the valve springs were removed and I slid them in and out a few times

[moizeau]

To be fair I'm pretty sure they are in 'spec' as they made a lovely 'plonk' noise once the valve springs were removed and I slid them in and out a few times

Hehe car prawn

[CitroJim]

To be fair I'm pretty sure they are in 'spec' as they made a lovely 'plonk' noise once the valve springs were removed and I slid them in and out a few times

Hehe car prawn