my wife has an MGB gt and when I was driving it this afternoon (quite high revs) I heard a big pop, lost loads of power, then it seemed to be ok.
I was only 2 mins from mother in laws house so drove it there.............

when I opened bonnet there is a hole in the block!!!

It looks as though there was a sight glass or something there. anyone any idea's?

The hole is in what lookes like a man made circlular depression on the dipstick side in the middle.

I want to know if this depression is a sight hole that can be replaced or is it a new block job or what?

Sounds like a core plug.

is it a pre-69 engine, 3- bearing? The old engines had a small TV fitted tuned into BBC1 so you could watch it should you ever run out of petrol.

or maybe like ^^^^ siad, a core plug.

quote:

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Originally posted by 02GF74
is it a pre-69 engine, 3- bearing? The old engines had a small TV fitted tuned into BBC1 so you could watch it should you ever run out of petrol.

or maybe like ^^^^ siad, a core plug.

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How would a popped core plug cause loss of power? Just curious.

Its interesting that you say it lost lots of Power but was then Ok.

It sounds like one of his core plugs is holed. When all the water came out I bet if he'd looked in his mirror there would have been loads of steam coming out. This would on a motor of that age have caused some temporary misfiring due to the damp on the HT leads and dizzy I suspect.

I hope he doesn't drive it any further!

Buy a core plug of the correct size, clean round the hole with some wet and dry, I use some permanent gasket seal like red foliac on it then knock the new plug in with a drift till it sits level with the block. The last plug I bought was 35p.

thanks for all the help, a new core plug is on its way and will be fixed by the end on the weekend


cheers