MG - Midget - 1974 1275 Oil leaking out of head.

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Sun 12 Oct 2008 13:35
Midget - 1974 1275 Oil leaking out of head. - Matthews
Hello Every one,

I have just got my self a 1974 MG Midget with the 1275 engine, Which has been converted to run on unleaded petrol.

But the head has an oil leak on the back of the head, There is a hole which looks like there should be a bolt in it, but i cant seem to find the bolt listed any where.

As you look at the front of the car the hole is on the right side of the head and is on at a angle.

Some one else told me that it has a mlf thread, and that it has got a very fine thread i am not sure how much of this is true.

Many thanks for any help or advise.

Matthew
Thinking that looking for a bolt in the middle of a hay stack is easyer then on the web!!!!



Edited by Dynamic Dave on 12/10/2008 at 17:04

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Sun 12 Oct 2008 22:07
Midget - 1974 1275 Oil leaking out of head. - I'm a Pane
Shouldn't worry too much-these engines love a bit of an oil leak! Seriously, if you have a decent old fashioned independent garage/mechanic or ideally an MG specialist in the area ask them - they will know the engine like the back of their hand being the ubiqitous 'A' series.
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Sun 12 Oct 2008 22:23
Midget - 1974 1275 Oil leaking out of head. - Number_Cruncher
>>the hole is on the right side of the head and is on at a angle.

Whereabouts on the head?

Is it quite near the front, just beneath and behind the thermostat housing, near to the front end of the exhaust manifold to head joint?

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Tue 14 Oct 2008 14:12
Midget - 1974 1275 Oil leaking out of head. - The Gingerous One
From my vague recollection of leaking oil from A series engines and rebuilding a couple when I was a youff back in early 90's.....

There's a hole in the face of the cylinder head that exists to allow oil to be pumped up from the block and into the rocker cover to lube the rockers. Similarly there must be a return for it as well, this probably rely on gravity for the return feed.

So the oil leak, if it is coming from the top of the engine must either be coming from the rocker cover & dribbling down or else coming from the head gasket where the oil is being pumped up into the head.
If it's the latter then either the head gasket is stuffed or else maybe the oil feed hole upto the head is blocked and the oil has to go somewhere, in this case out.

Head bolts might not be torqued down evenly or correctly ?

hope that helps ?

cheers
Stu
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Tue 14 Oct 2008 14:27
Midget - 1974 1275 Oil leaking out of head. - Number_Cruncher
to lube the rockers


Yes, this was the drilling I was asking about. The drilling isn't straight up, so, there's a plug - I suspect it is this plug that has come out. As this plug is usually not removed during normal work, I doubt if it has ever been listed as an available part.

I've never taken this particular plug out, but, I wouldn't be at all surprised to find it's a small BSPT thread.

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