C4 VTS 180 - Cylinder Head Rebuild after Timing Belt Failure

[Cheeros]

Dear fellow Citroën enthusiasts,

I'm looking forward on some advice on rebuilding the Cylinder Head of my Citroen C4 VTS 180 (EW10J4S / RFK engine).

Unfortunately, the timing belt snapped very prematurely, about 40k after a full replacement by myself of belt, water pump, pulleys, and also the full ancilliary belt kit. This resulted in 14 out of 16 valves bent in somewhat mid position, and just minor 'kiss marks' on the pistons. Quite a lucky outcome in my opinion as I feared broken valves, smashed into the cylinder head.

Currently, I'm stuck in removing the inlet pulley, which is the one with Variable Valve Timing. I just cannot manage to get the E14 Torx bolt removed. Tried to follow the OEM way, with Spanner 23 on the Camshaft and E14 elongated ratchet on the bolt, but no success… Also tried the air wrench, no luck with that and afraid to damage the VVT pulley. Back to breaker bar and spanner, extended with some pipe but no movement at all. All of this while the E14 bolt head isn't getting better.

Some considerations I had:
- It must be right handed thread, just like the exhaust pulley bolt that came loose easily
- There could be Loctite on the tread, placed by previous mechanic. Thinking of heating the bolt while kind of shielding off the rest of the pulley.
- Potentially welding a large nut on the E14 bolt to be able to use even more momentum.

Also Tried:
- Removing the Camshaft plus Pulley altogether, but seemed impossible due to design.

At this stage, I'm looking for advice on how to best continue the disassembly. Anyone of you that have faced the same issues? Any advice is welcome on how to get this bolt loose, or perhaps other tips/tricks that might come in handy in getting this lovely car back on the road.

Best Regards,

Cheeros.

[mickthemaverick]

This video may give you and idea

[Cheeros]

This video may give you and idea

Thanks for the reply Mick, however I'm afraid this method isn't recommended for Camshaft Dephaser Pulleys like the one on the inlet-side.

Don't want to put too much stress on the dephaser mechanism. Method would be fine on the Exhaust Pulley, which also came loose easily with the 'spanner-on-camshaft method'

Already had to put an incredible amount of torque on the Inlet-side bolt, which is quite a challenge with just a large spanner with extension on the cam and an extended breaker bar with E14 on the other side. In this way, no torque is put on the dephaser mechanism, but on Camshaft bolt vs Camshaft only. See picture below for illustration:

[mickthemaverick]

In view of your situation I would try locking the cam with your big flat ended spanner and then use the impact wrench alternating direction of rotation in very short bursts to try and jolt it free. Have you got a powerful impact wrench? I have a big boy for that sort of work which gives 1396 NM torque. https://www.cef.co.uk/catalogue/product ... -batteries It is the sort of gun you may need.

[PaulC5]

If you will need to spend a lot on an impact wrench, as an alternative ask a dealer if they could undo it and pay them, especially as it looks as if the bolt head is chewed up.