850 Mk III Oil Pump survey

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It appears that there is a conflict in most if not all the Commando factory workshop manuals regarding the torque for the oil pump nuts. Section A calls for 15 lbs./ft., but Section C30 calls for 10 -12 lbs./ft. That issue has been resolved, but another issue cropped up.

Are 850 Mk III oil pumps secured via studs and nuts, as older models, or do they use bolts and washers? Or were both methods used?

I'd like to start a survey of Mk III owners and anyone who has removed the timing cover from a Mk III 850 engine. How is the oil pump secured in your engine? Please reply with year and month of manufacture and/or engine number. I need this information to make accurate comments in my edit of the 850 Mk III workshop manual.

This all started at post 75 of the thread linked below:

https://www.accessnorton.com/Norton...manual-parts-catalog-errors-2017.23083/page-4

Thanks in advance for your assistance.
 
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Morning Chas
Both my Mk3s have bolts securing the oil pump (build dates, 3rd month of 75 on Suzi and 7th month of 75 on Mitzi)
 
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Can't / won't pull the t.c. off just to take a look on both my MK 111 's , but will keep this post in mind next time the cover(s) off. I think it's a 2 bolt affair. I remember someone telling me with my 3 750's past to upgrade to bolts from studs for them so I did. I suffer from C.R.S.
 

mean gene

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Not to muddy up you survey, but also if there is a gasket under the oil pump.. I have never found a gasket but they always want you to put one in!
 

L.A.B.

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Not to muddy up you survey, but also if there is a gasket under the oil pump.. I have never found a gasket but they always want you to put one in!

Fitted to engines from serial 150120 (approx. Sept. 71) so a Mk3 should have the gasket (38).
 
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Engine number 328906, build date 3-75. Bolts. It was a low mileage example I bought from Randy Baxter well over 20 years ago. Largely unmolested, by the hands of bodge, but it hadn't run in years. Upon tear down, the bolts bothered me until I saw the pic of the MKIII cases on Dave Comeau's website with bolts.
 
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Engine number 328906, build date 3-75. Bolts. It was a low mileage example I bought from Randy Baxter well over 20 years ago. Largely unmolested, by the hands of bodge, but it hadn't run in years. Upon tear down, the bolts bothered me until I saw the pic of the MKIII cases on Dave Comeau's website with bolts.
Don,
Check your "conversations" [aka private messages] I sent you one back on June 10th. Refer to post #70 in the link below on how to access them.

Finding older [more than 4 days] Conversations
 
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