I would replace the Valve Cover Gasket first.

I would also try tightening the Oil Filter Housing Bolts firs before I tried raplacing the Gasket.

I do not see how you could have enough room to carefully clean the area with the Oil Filter Housing loose but still attached to the Oil Cooler Lines. So, I believe you would have to remove the Oil Cooler Lines where they attach to the Oil Filter Housing.

You need all the room you can get to prevent a piece of Gasket Material or dirt from getting into the Oil Gallery. (Clean and degrease the Engine before starting work.)

You will most likely need to grind a 24mm wrench thinner and use it to keep the fittings between the Oil Cooler Housing and the Oil Cooler Line Nuts (1-1/16inch or 27mm Wrench) from turning.


I would look in the DIY section to see if some one has a write up on it.

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84 300D, 82 Volvo 244Gl Diesel