G2 CRANKCASE BREATHER

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Janet
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Re: G2 CRANKCASE BREATHER

Post by Janet »

Owing to my previous effort being totally off the mark I won't offer any kind of suggestion except that this link may be useful in future for finding what goes where.

http://archives.jampot.dk/book/Spares_l ... e_View.pdf

Some of the later models are a little bit different and you need to know what they are when replacing them, but this drawing has helped me enormously.
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Ozmadman
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Re: G2 CRANKCASE BREATHER

Post by Ozmadman »

rob99 wrote:Thanks guys the white stick hole definitely has thread in it and the witness on the casing is for the bolt to fasten flat to, we could see the alloy stator and inform my dad about it needing to keyed to the shaft and that he should check.

The other hole is there something that's supposed to go in there of is it just left like that.

Most appreciated help guys
The bolt when fitted will screw into the alloy stator to stop it from turning as that is the fixed part. Rotating inside of that is the rotor, this is the part Colin mentioned that is keyed onto the crank. The rotor and stator and the crank itself have a hole in them so once every revolution of the crank the holes in the rotor and stator line up allowing the engine pressure to vent through that other hole which has nothing in it. It is important that you do have the rotor fitted to the crank (mine BTW was missing!!!) as this also acts as a spacer between the two crank bearings that side as you tighten the crank nut after assembling the primary(timing chain gear) and alternator rotor. You should have at least .020" (20 thou) of free play (pushing and pulling the crank) when you assemble the engine BEFORE putting on those parts and tightening that crank nut fully, once it is tightened there should be no free play.
Last edited by Ozmadman on Fri Feb 12, 2016 12:21 am, edited 1 time in total.
Paul
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rob99
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Re: G2 CRANKCASE BREATHER

Post by rob99 »

That's brilliant thanks guys great response a big thanks from myself and my dad.
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