Blowing Oil out of breather

[Eder Profile]

Hi, I have a 1963 AJS 14 CSR and it has been blowing a lot of oil out of the breather. I initially thought it was a clogged oil filter but it has a wire mesh filter as opposed to the felt type and it is clear. I have stripped the engine and found a small flat on the oil pump guide pin, which no doubt has contributed to the problem but I was wondering is there anything else I should be looking for?

Thanks in advance,

Eddie

[BigAl350 Profile]

Yes. Is it knackered? Like in excessive blow-by past the piston due to wear?

Al

[Eder Profile]

Thank you, you have confirmed my suspicions. The engine was supposedly 're built' 1200 miles ago but when I took the head off, the piston, although new, had too much movement in the bore, the ring gap being 25 thou as oposed to 8 to 13 thou. It has been re-bored at some stage, not very well it would seem.

Regards,

Eddie