Citroen XM Forum

Alasdair. Your attention to work level dooing this is far higher then I've ever done. Maybe I've been lucky. I think I've only had a head off one once to do a head gasket that popped rather then over heated.. Then three times dooing rocker fingers. Which didn't need heads off.

Hats off to you for your very detailed rebuild...

Stickfinger wrote: Sat May 29, 2021 1:24 pm what a ball ache....the space at the side of the springs greatly restricted my available tools !.....I had to modify my spring compressor and use a large nut to be able to manipulate the valve stem collets into place.

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What pillock thought 12valves engines were a good idea

Weld some, say 20mm, downward facing legs onto the compressor clamp foot, to give rigid points and more space to access the collets.

Just as a matter of interest, how much time do you think you have put into this head job, so far?

Iirc, I gave book time as 17.5 Hrs and probably 30 Hrs, Diy on the floor, complete job.

Time, imposable to say really as I send 1/2 to 1hr segments...

Rockers, hydraulic tappets etc all on.....should have done more but a good friend is here and this weekend is the first I have had anyone here since the end of September 2019.
....and this lot have been messing about all day

Nice new Cam shaft seal.

Moving on.

Now that lower shot of the rear assembly is brill. It shows me fairly clearly that if I get the inlet off and remove the air intake pipe to the turbo and possibly outlet I can get at the wastegate. Stupidly when I had the lump out on one I've got here which needed an autobox at 262k miles the wastegate has always been partly stuck open so it's never had full turbo wack into the engine. Making it an lpt sort of setup.. I looked at it when ut was out and the waste gate had jammed. I freed it up and stuck it back in the car after box swap. After a few revs again it stuck partly open again. So I'm hoping it's the pressure actuator and not something inside the turbo holding it open..

You can just...and I mean just, reach the actuator mechanism with the upper intake removed.
My experience is that the wastegate linkage is set so the spring pressure is too light when the wastegate is closed, the linkage has reached the end of it's travel, so a turn or two of the link holds it closed better.

Muuuummm, interesting.

Talk to be about adjusting/checking the Turbo linkage --before-- I put it all back in the car.

As simple as this ?

Just pull on the wastegate arm.. Ie pull it into the vaccum housing and make sure it's free to move.

Move was stuck but when I pulled on it it freed up and was OK then till I put it all back in ran it revved it and it stuck again..

Will should know better then me if its lengthen the waste arm or shorten it to allow more. Boost.. I'm not 100 percent certain.

I did not think you could generate more Boost with an EPIC (fail) pump