losing oil

Correct. Do NOT dismantle the upper cylinder head portion without first removing the timing belt, cam pulleys and setting the engine to TDC and locking the cams. Slacken the retaining bolts progressively 1/2 turn each all the way around from the center working outwards diagonally- the haynes manual shows the correct order.

Use some gasket remover or cellulose thinners to remove all traces of old "gasket" from both surfaces, and ensure everything is perfectly clean before you start taking it all apart and before putting it back together.

For re-assembly you will need the cam straps both ends (to hold the cams in the upper portion and in correct position) a small mo-hair roller, the correct Volvo sealant (NOT silicone!!) and 2 pull down tools, which screw into plug holes 2 and 4 with which you pull the upper portion back onto the lower portion and into position before you insert the bolts which hold it on.Be careful and take your time that it is indeed pulling down square and onto the dowels against the valve springs.

All the special tools can be made in a reasonable workshop- again the haynes manual shows these in detail.

Torque the upper cam carrier down to the correct figure.

Use a new cam belt, and turn the engine over twice by hand and re check the timing marks before you attempt to fire it up.

If you dont feel capable of doing this- leave it to an expert- i.e. someone who has stripped the modular engine before- it is not something you can do with a 3/8 spanner and flat blade screwdriver!!

Tim..

Thanks for your help.