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MG MGA - Smoke from Rocker Cover - Normal?

I have a stupid/embarrassing question...

The other day after driving the car on the highway, after parking, I opened the hood and realised the was a bit of white smoke coming from the engine bay.
The smoking was coming from the rocker lid. I opened it and there is was. It smokes a bit and is not noticeable unless you open the hood.
I checked the oil level and it seems fine.

Is this normal? I guess the oil temp was kind of getting hot but the water temp was normal...

My car has an aftermarket rocket cover without a breather tube (but I understand the breather is incorporated in the lid which allows the smoke to escape.

Just wanted to make sure that is nothing bad before I take it on a 4h drive during the weekend.

Any comments welcome.

Gonzalo Ramos

Gonzalo,
Your rocker cover should be vented, and the forward tappet cover should have a downdraft tube for venting. The tappet cover is on the driver's side of the engine, and the vented cap can give off fumes. I don't know how much venting you are getting from a vented cap, but it may be OK. Somebody else should reply on that. A wisp of smoke from the vent cap is possible if the car is cold and goes for a short run, but shouldn't be there after a highway run, as you should have 'boiled out' the condensation in the oil during the drive. White smoke could indicate a head gasket. Check your coolant level, take it for a drive and check it again. If it looks like trouble, you may want to do a hot compression check on the engine.
Mike Parker

It looks to me as if you are getting some crankcase pressurisation which is indeed venting from the rocker cover. This is caused by wear in the piston rings/cylinder bores and should firstly be checked by a compression or preferrably a leak down test.
Iain MacKintosh

You might want to check out Barney's article on engine smoke

http://www.mgaguru.com/mgtech/engine/be104a.htm
F Valenzano

This thread was discussed between 28/04/2010 and 30/04/2010

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