Blowing Oil out of breather

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Eder
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Posts: 6
Joined: Wed Mar 30, 2011 10:11 pm
Location: CO ARMAGH UK

Blowing Oil out of breather

Post by Eder »

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
E Frazer
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BigAl350
Posts: 154
Joined: Sat May 22, 2010 4:32 pm
Location: BERKSHIRE UK

Blowing Oil out of breather

Post by BigAl350 »

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

Al
Al Bolton, G4VSQ
1960 Matchless G5 (Off the road for now, maybe for sale?)
1960 AJS Model 8 (Just passed MoT)
1962 AJS Model 8 (Still lurking in a Devon shed in bits)
Eder
Member
Posts: 6
Joined: Wed Mar 30, 2011 10:11 pm
Location: CO ARMAGH UK

Blowing Oil out of breather

Post by Eder »

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
E Frazer
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