MGB Register Forum

Thanks both, to be fair to the engine guy, we were trying to do each other a bit of a favour. He has done lots of A Series engines but not any B series so he didn't charge a lot for the experience. He re built it last year and i ran it over summer and then took it back in January. he has tried to sort the issue but it doesn't seem to have worked. Ill def try the latex glove over the oil cap and dry and wet compression tests at the weekend and see what results we get.

Many Thanks,

So did the latex glove over oil filler cap and it dragged it straight in, so doesnt seem to be an issue with crankcase breathing.

Dry compression test 170psi on all cylinders, wet compression test 220 psi so seems like its rings that need to bed in.

Reckon a long drive tomorrow will hopefully get then bedded in

Thanks all for the advice its been very helpful

Nik

That's some progress I think Nik. I hope that the bores have been honed correctly to help bedding in, and I don't want to be unduly pessimistic, but that is quite a difference in readings and I wouldn't expect that on a newly rebuilt engine.
I have built several A series and B series engines and not had any of them smoking after new pistons and a rebore.
If it doesn't stop smoking soon I think you have a good case to get some redress against the engine builder.
Do you know what make of pistons were put in, and what overbore size they were? I have usually tried to avoid County brand as their quality control can be a bit poor - each piston needing to be hand fitted to each bore due to inconsistent sizes.

Ian F

Hi All,

Did the Daffodil run Sunday which was great, still burning oil so going to get a 2nd opinion.

Any recommendations in the West Yorkshire area for good MG Mechanic/garage

Many Thanks,

Nik