To much oil pressure on 1957 M30 twin

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REW
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Re: To much oil pressure on 1957 M30 twin

Post by REW »

Where is it leaking from John?
Ron

1951 Matchless G3L thumping round the Durham Dales.
SPRIDDLER
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Re: To much oil pressure on 1957 M30 twin

Post by SPRIDDLER »

1608 wrote:Hope you are keeping well, don't seem to hear from you so much of late. My point being, extra breathers may ease the leakage of oil, but not correct the cause.
Yes, very well John. Back yesterday from riding the 'Mutchless' to our section's 5 days camping rally in France - aka the annual 'Day Centre Rally'.

John Grew wrote:Ok so sit there and feel smug , you have made your point ,but have you got any idea what might be causing it?
Apologies John; I know absolutely nothing about twins but my off-topic point was that one can spend much time and suffer frustration with fixes and modifications when the cause is a fundamental assembly fault. But it would help to know where the leak is.

(Ah, do I hear the 'All clear' siren?)
'There is a tide in the affairs of men
Which taken at the flood............'
petert120r
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Re: To much oil pressure on 1957 M30 twin

Post by petert120r »

Check your crankshaft breather - see recent post "Model 31 oiling problem"
John Grew
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Re: To much oil pressure on 1957 M30 twin

Post by John Grew »

I have just spoken to Steve at AMC Classics and he came up with a few suggestions most of which have so far checked out but due to the amount of oil that it is chucking out of the rocker box Steve suggested that the metering valves in the heads might be missing so it is heads off time , but not for a bit as I am away to Normandy on the G3L in the next day or so. Keep you posted
John
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1608
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Re: To much oil pressure on 1957 M30 twin

Post by 1608 »

Metering plugs were discontinued for a few years and then re-introduced, in I believe 1962. They were not present in my G12 when I first took it apart. I fitted the plugs and it stopped over-oiling of the top end.
Richard Mills
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Re: To much oil pressure on 1957 M30 twin

Post by Richard Mills »

I also don't know anything about the twins, but.....
If you vent the rocker box and cause crankcase air to travel up to the rocker box, will this result in problems for the oil that had been fed to the top end trying to drain down to the sump? Suppose that it will depend on the anatomy of the pushrod tunnel etc..
John Grew
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Re: To much oil pressure on 1957 M30 twin

Post by John Grew »

Now back from Normandy and will see what I can find by putting it back as it was and starting again . I do have some checks to do as the result of speaking to Steve so my fingers are crossed.
John G
56G80S
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Re: To much oil pressure on 1957 M30 twin

Post by 56G80S »

John Grew not listed as a member but surely John Grew was one of the Club's earliest members - unless it's a coincidence.

Johnny B
MikeM.
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Re: To much oil pressure on 1957 M30 twin

Post by MikeM. »

There are two John Grews would you believe. I thought the John Grew I knewhad moved to Sussex when I first saw the posts.
John Grew
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Re: To much oil pressure on 1957 M30 twin

Post by John Grew »

This John Grew is the hansom one but I cant speak for the one up norf but he might be as well
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