8 replies to this topic

[Yams]

Now i don't know if this is possible, but...

 

Had an MOT advisory on another car, apparently its leaking a little oil. I inquired and the MOT man said it was leaking from the back of the cylinder head and it would need a new head gasket soon.

 

Obviously my first reaction was 'thats going to be expensive', as its a modern car, not a classic mini, thus not something i would wish to attempt myself.

My second reaction was more like 'How is that even possible?'. As surely if its leaking oil, the seal between the block and head is gone? It doesn't feel like the head gasket is gone when driving the car.

 

So the question really is.

Is it possible for an oil leak to appear at the head gasket without losing compression, (so the car still drives normal)?

 

Many thanks

Yams

[Carlos W]

It is possible, depending upon the location of oil ways but I'd be checking rocker cover gasket first

[dennismini93]

as above check the rocker gasket first. my head gasket blew between 2 and 3 but didnt affect the oil or water at all so anything is possible 

[CityEPete]

The head Carries water, oil and the combustion gases in one form or another, it's possible for any one or more of those to leak to themselves, to outside the engine or between each other in any combination. Water to water would probably make no difference to anything, same as oil to oil or combustion to combustion if it's slight, any one thing leaking out on it's own could show as an oil leak or water leak or power loss, mixing two or all three can give lots of various results, pressured cooling, mayonnaise in the oil, over heating etc etc. That's why it's the easy option to suggest it at fault for most symptoms.

[cradley-heathen]

i think the mot guy just said that off the cuff, assuming you wouldnt think anymore about it, either that or hoping you would pay them lots of money to do it!

 

either way its a stupid think to say really as without doing some serious investigating it would be very hard to tell where the oil was coming from!

[The Matt]

Depends on the car. On some engines it's blatantly obvious when there's an oil leak from the head gasket. What car/engine is it?

[The Matt]

And yes, perfectly feasible to lose oil through a head gasket and not lose compression. The question is though, what caused the gasket to fail?

[Yams]

And yes, perfectly feasible to lose oil through a head gasket and not lose compression. The question is though, what caused the gasket to fail?

 

Probably something to do with it having just over 100,000 miles on the clock now. Its a MkII clio

[se_juggles]

Its easy to change mate. Pretty much the same as a classic mini still lol.