XUD Cylinder Head Issues and mysterious Evolution Document

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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by white exec »

I have ground shims down (in Rover 2000 days), but it's hard going, and not easy to get the ground surface dead flat and parallel. Best to do your correcting calculations, and buy new ones where needed. Some swapping-around might be possible, if the maths permits.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

white exec wrote:
06 Sep 2021, 19:55
I have ground shims down (in Rover 2000 days), but it's hard going, and not easy to get the ground surface dead flat and parallel. Best to do your correcting calculations, and buy new ones where needed.
I think I have two matching... :cry:

I read somewhere that they are £11 a pair? :shock:

Wonder how old the part numbers are on Jim's spreadsheet?

0906 52 = 2.875
0906 82 = 2.900
0906 53 = 2.9
0906 84 = 2.975
0906 54 = 3.025
0907 07 = 3.05
Last edited by myglaren on 06 Sep 2021, 21:25, edited 1 time in total.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by white exec »

Those pt.nos. all coming up, and lots of others too. All still shown as available.
Have edited in thicknesses above.
Marc might have access to prices.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

white exec wrote:
06 Sep 2021, 22:05
Those pt.nos. all coming up, and lots of others too. All still shown as available.
Have edited in thicknesses above.
Marc might have access to prices.
Thanks Chris.

They do indeed still match Jim's spreadsheet.

Not sure whether to bite the bullet and just call Citroen for prices.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

Well. Citroen only have ONE shim in stock and NO head gaskets.

Will take a look at MisterAuto
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

So whilst the car is stripped down I am certainly thinking of doing the heater matrix.

When I last bought one for Sylv's ZX, it cost £40 and lasted 18 months and was either Valeo or Behr I thought. Citroen wanted £100.

On Autodoc, they now vary from £14- £21!!!

This seems outrageously cheap (sort of offsets the pain and anguish of doing the job).

It's surely worth going for the Mahle one at £21? Any thoughts, objections and/or recommendations greatly appreciated>

Also, what other tasks are worth doing whilst dash is out and cylinder head off?

Isn't there a transistor or something on the blower motor that needs replacing?

And I must say I look at the brake doseur valve looking all innocent and dry on the engine side. Is that worth fiddling with whilst it's all stripped?

So far, I intend to do heater matrix, hose to it, head gasket, timing kit and all tensioners now (changed my mind from just the belt), water pump and offside engine mount which looks cracked and might do the one at the bottom to the rear around the sump area.

Any other suggestions for what I should do, I've wiped all the metal pipes down and intend to inspect them thoroughly. Must inspect turbo which I have yet to do.

Thanks for your continued support and interest.

EDIT: The offside brake sensor loom is broken. The one which is clipped to the subframe. Is this still available I wonder?
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by white exec »

Rhothgar wrote:
07 Sep 2021, 10:02
Well. Citroen only have ONE shim in stock and NO head gaskets.
Will take a look at MisterAuto
None of those shims are showing NFP at Citroen, so presume all are still available.
Your dealer may well have none (one?) in stock, but that's to be expected.

On the heater matrix, Nissens have a very good reputation, as have Mahle (Behr-Hella).
I would avoid the very cheap ones.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

white exec wrote:
07 Sep 2021, 13:45
Rhothgar wrote:
07 Sep 2021, 10:02
Well. Citroen only have ONE shim in stock and NO head gaskets.
Will take a look at MisterAuto
None of those shims are showing NFP at Citroen, so presume all are still available.
Your dealer may well have none (one?) in stock, but that's to be expected.

On the heater matrix, Nissens have a very good reputation, as have Mahle (Behr-Hella).
I would avoid the very cheap ones.
I will try the local dealer. I tried one up the road to avoid embarrassment over coughing and spluttering at the price.

I nearly asked about Nissens because I have heard that name somewhere before.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

Just got the cylinder head back from engineer.

He had to take off 0.014” (0.356mm) which is quite a lot!

It’s still not perfect where the corrosion had eaten the steel away by some areas of the water jacket but I will check their position against the new gasket and use a bit of Reinz gasket sealant in this areas if necessary. I think that should be fine but the clearances do concern me.

Existing gasket was 2 notch and 5 notch is only 0.15mm thicker.

Should I be worried about valve to piston clearance?

And the heater matrix - is mine a Behr system or Valeo from the Citroen info please? May as well order the correct one rather than guessing / assuming they are the same.
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Re: XUD Cylinder Head Issues and mysterious Evolution Document

Post by Rhothgar »

Reinz, the original gasket manufacturer, do a 1.7 mm thick gasket.

Can anyone tell me whether the tolerances are that tight on this engine that 0.11mm makes a difference. I know the engine is an interference fit as far as valves are concerned.

I have not measured height of pistons above the block.

Can I risk a 5 notch at 1.59mm when the 2 notch was only 1.40mm and 0.356mm has been skimmed off. Surely the valve to piston clearance doesn't get down to tolerances of 1/10ths of a millimetre?

All things being equal then using the 1.7mm. gasket will mean valves sit 0.056mm lower than they did when the 2 notch gasket was on.

I also think 1.7mm. is the thickest available and there is nowhere else to go after that if it goes again at some point in the future. I suppose the real answer here is deal with any leaks as soon as they develop.

Need to get a gasket and all ancillary kits ordered today ideally.