QuestionHi Barrie I just purchased a 1979 MGB and have an oil leak...not sure if is the valve cover or the head gasket I would like to clean the engine first but not sure have to go about that? Thanks in advance for your reply.
AnswerHi Dan. I would take the rocker cover off and inspect the cork gasket, and the two rubber seals where the holding bolts go through. If they look in the least bit suspect, just fit new ones. They are quite inexpensive. Glue the gasket to the rocker cover with a thin smear of Hylomar (non-setting gasket cement).
Also the oil filler cap contains a breather filter, so it should be thoroughly washed with gasoline in a metal or glass container. Gas is nasty stuff, so take care of yourself. Do not do this indoors, do not breathe the vapour, avoid naked flames, and wear disposable gloves.
After putting everything back together, clean all traces of oil from the top of the engine with a rag lightly impregnated with the used gasoline, and dry it with more rag or kitchen paper. (I am not guilty if your wife finds out).
Now start the engine, and look to see if oil is still getting out anywhere. It should be obvious where it is coming from. The head gasket is below the head, and typically leaks between cylinders 2 and 3, on the distributor side of the engine. Do not be tempted to tighten the head down some more. It never works and it is just a waste of time. Fitting a new head gasket is a relatively easy job.
