Socket set

Information relating to the Matchless G9 or AJS Model 20 500cc twin
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Re: Socket set

Postby Yves.Astein » Sun Jun 07, 2020 6:15 am

Oggers wrote:
Incidentally, I think (pray more like) the dreaded dynamo seal has abated a little, but I'm still getting a drip from the lower part of the frame below the dynamo. Anything else it could be - apart from badly assembled crankcase halves?....Chaincase is a separate issue...

You do have the small paper seal (015034) around the Oil filter channel installed ?

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Re: Socket set

Postby Groily » Sun Jun 07, 2020 8:33 am

The dimension of the nuts is 0.525" Across the Flats. That is 13.3mm in round numbers.

The correct tool is the socket you referred to if it's slim enough, or one from the Club who keep them especially for this task. Or a 1/4 whit box spanner as Mick said if you really don't want to be the proud possessor of a very inexpensive 3/8 extension bar, such as is available from any number of places, eg here: ... B000LFS0DS

No good ever came of using the wrong thing. A rounded nut down there would be a complete pig to get undone. And as I think I said before, tightening up willy-nilly to try to eliminate a weep at the head or base gasket is a poor plan if the problem isn't simply under-tightening by the PO.
On which point, you'll need a torque wrench if you want to be spot-on, or you need to have a good 'feel' for what is about right, and get things even across the 4 nuts on each head.

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Re: Socket set

Postby 56G80S » Sun Jun 07, 2020 11:37 am

On Groilly's point about torque wrenches, I use them more than I used to. I think, particularly in cases like head bolts, it is less about the absolute tightness figure but more about getting the corresponding level of tighness across all nuts / bolts; evenly tight. I've developed carpal tunnel and some varying levels of pins and needles / numbness (different from between the ears) in my right thumb, forefinger and middle finger.

I now have a 3/8" torque wrench as well as the 1/2" as the latter does not go down to the lower figures. With a couple of adaptors (3/8" to 1/4" and 1/2" to 3/8") that does the trick for me.

Johnny B

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Re: Socket set

Postby Mick D » Sun Jun 07, 2020 11:46 am


A breaker bar, spring balance and some maths are a torque wrench for the thrifty :) ;)

Regards Mick

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Re: Socket set

Postby Oggers » Sun Jun 07, 2020 3:37 pm

1/4 ww Apollo box spanner bought off Fleabay for 3 quid. We'll see if it fits down the 'ole!

Paper seal - well that is an engine strip if it is absent, and I am not doing that just now! I do think at some stage the whole thing needs to come apart and reassembled - properly! One for Winter.....


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