Pressed steel cover gaskets of all sorts produce sealing problems in abundance, especially when cork gaskets are used. Multi-piece gaskets are used where the designer has saved weight and cost by such innovations as shortening the crankcase and deepening the oil pan and at the same time increased the chances of oil leaks.



The ends of multi-piece gaskets can be sealed with a dab of a high quality rtv silicone sealer or an adhesive sealer such as one of the special Bostik range which has been recommended by so many vehicle manufacturers.

Beware of using an excessive amount of sealer because as much squeezes inwards as outwards and the possibility of future problems are increased.



Cork gaskets should be fitted dry to avoid the problem of a sealer lubricating the surface and the gasket creeping out under clamping force instead of being compressed. Lightweight steel covers and pans always distort around the bolt holes regardless of how gently the bolts are tightened and sometimes even a dry cork gasket will be pushed from the joint and ruined.

The necessary blobs of sealer can be the death of the gasket so it is best to tighten in stages - the first stage is to merely pull the bolts down evenly so the gasket is nipped but not compressed. After about an hour the rtv will have developed a skin but will not have cured so the bolts need another half-turn and then leave the job until the cure has completed before applying the torque wrench or vast experience and finishing the job.



When the steel of a cover is particularly lightweight I find great benefit in gluing the gasket to the steel with a latex/solvent contact adhesive such as Evo-stik.