207 1.4 i 16v 90 KFU head gasket change

[perrye]

Hi all
2006 207 (A7) 1.4 i 16v 90 (KFU) 177000 km.
VIN VF3**************[VIN obfuscated, can be read by forum staff]
Oil leak front right of engine.
I want to change the head gasket (never done one before) and would like to confirm that old instructions I have are correct.
1. Rotating crankshaft backwards (or not)
In documents of setting timing it says to ESSENTIAL : Never turn the crankshaft backwards.
But in Peugeots camshaft-document it says
Turn the engine 1/4 of a revolution in reverse. That is not mentioned in Citroens KFU instructions.
I'm confused, should it rotate back or not? What is the point of that, getting the pistons all in same level, like it's done in Ajusas video?
In most videos I've seen they never do that (only in Ajusa to be exact).
That makes me wonder if that is (again) a mistake in PSA:s documents?
2. Using Liner retaining clamps 0132-A1Z (or Citroen 81132-T.A1)
Again, I've not seen them used in videos, beside that Ajusa. Are they really nessessary? Have you used them when done this?
3. Skimming the head
I know there are old TSB B1AW22Q0 for this car Oil leak (gasket failing of oil channel in front right corner of engine). I think that the leak is exactly that. In your opinion, should I get the head skimmed? Is it nessessary? It is a cost and time issue because it takes time to get it done quite far away from the garage..

I would very much appreciate your knowledge and opinions.

[wheeler]

Has the engine overheated? If not it probably wont need skimmed, I would always check with a straight edge & feeler blades though. I wouldn't skim just for the sake of it. Do you know if it has ever been skimmed previously?
Liner clamps are only needed if rotating the crankshaft when the head is off, if you need to rotate there is a risk of dislodging the liners & damaging the seals.
You can normally improvise with some bolts & big repair washers.

[perrye]

Thank you for your response.
I bought the car for my daughter four years ago, it had then 109 tkm. I have not any info about skimming before that and there has not been any coolant loss for the past four years.
Only reason to change it is the oil leak and since the car is my daughters I can't be watching so often, as it is too near aux- and cambelt.
So if I understand correct if I don't turn the engine there is no reason to clamp it? And I can't see any reason for turning.

[wheeler]

So if I understand correct if I don't turn the engine there is no reason to clamp it? And I can't see any reason for turning.

Correct

[ozvtr]

Only reason to change it is the oil leak and since the car is my daughters I can't be watching so often, as it is too near aux- and cambelt.

Most of these gaskets have a stupid "key hole" shaped metal insert that de-laminates from the fiber portion of the gasket. The next phase of the failure is oil in the coolant. Elring gaskets are all fiber, no insert.

So if I understand correct if I don't turn the engine there is no reason to clamp it? And I can't see any reason for turning.

You shouldn't turn the engine backwards while the cam shafts are installed in the head. Read that any way you like. However there shouldn't be any harm in turning the engine CW to #1 and #4 top dead center, then backwards 1/4 turn, before removing the cam belt and head. This way you won't need the cylinder clamps.
The KFU engine has cam followers and the cam shaft pushes (semi) directly onto the valves. Once the cams are installed, some of the valves will be pushed down and protrude from the cylinder head. If any of the pistons are at TDC AND the camshaft(s) are installed randomly, it's possible that the valves and pistons will contact.
The camshafts need to be removed to gain access to the head bolts. Therefore the camshafts need to be installed AFTER the head is installed. So the pistons CAN NOT be at TDC when the cams are installed! That's why the pistons are moved to the "half way" position. This way the cams can be installed AND rotated without fear of the valves contacting the pistons.
During re-assembly, the camshafts are pinned in position and the cam gear retaining nuts are torqued. Then the crankshaft is turned 1/4 turn CW and pinned.
Engines that have rockers, can have the camshafts installed without worrying about where the pistons are, until the rocker train is installed.

[ozvtr]

One thing wrong with ajusa's video is measuring the top of the "block", you can't do it! At least not with the engine assembled.
The liners need to protrude above the top edge of the block. Typically it's 0.05 to 0.1mm.
It is possible to measure the protrusion with a straight edge and a feeler gauge. But you cant measure the flatness of the top edge of the block (again, not while the engine is assembled).

[perrye]

Only reason to change it is the oil leak and since the car is my daughters I can't be watching so often, as it is too near aux- and cambelt.

Most of these gaskets have a stupid "key hole" shaped metal insert that de-laminates from the fiber portion of the gasket. The next phase of the failure is oil in the coolant. Elring gaskets are all fiber, no insert.

So if I understand correct if I don't turn the engine there is no reason to clamp it? And I can't see any reason for turning.

You shouldn't turn the engine backwards while the cam shafts are installed in the head. Read that any way you like. However there shouldn't be any harm in turning the engine CW to #1 and #4 top dead center, then backwards 1/4 turn, before removing the cam belt and head. This way you won't need the cylinder clamps.
The KFU engine has cam followers and the cam shaft pushes (semi) directly onto the valves. Once the cams are installed, some of the valves will be pushed down and protrude from the cylinder head. If any of the pistons are at TDC AND the camshaft(s) are installed randomly, it's possible that the valves and pistons will contact.
The camshafts need to be removed to gain access to the head bolts. Therefore the camshafts need to be installed AFTER the head is installed. So the pistons CAN NOT be at TDC when the cams are installed! That's why the pistons are moved to the "half way" position. This way the cams can be installed AND rotated without fear of the valves contacting the pistons.
During re-assembly, the camshafts are pinned in position and the cam gear retaining nuts are torqued. Then the crankshaft is turned 1/4 turn CW and pinned.
Engines that have rockers, can have the camshafts installed without worrying about where the pistons are, until the rocker train is installed.

Thank you for clarifying, really took me a while to understand this but now I get it. I would probably done this wrong without your message, big thanks!
And good to know that Elring gasket is proper one since I already ordered full gasket set from them.