G5 Oil Leak

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
starfield181
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Re: G5 Oil Leak

Post by starfield181 »

Wow Paul what a comprehensive description. Found the bits on the spares site so will order some anyway. Couple of further questions if I may. Did you use the paper gasket between outer/inner cover or just sealer. I normally use Wellseal.

The Neill book mentions removing the ratchet nut 41340 and ratchet 41283 before removing the cover but I struggle to see how they can be seen let alone undone until the cover is off. Am I missing something here?

Finally (well in this post anyway), Neill also mentions removing a gear indicator bolt but my bike does not have one nor any obvious place for it to affix. The cover does have gears numbers marked though.

Thanks

PeterF
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Janet
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Re: G5 Oil Leak

Post by Janet »

starfield181 wrote:It's beginning to look as though the vast majority of oil that has been leaking from my bike is coming from the kickstart shaft. Having let it stand for nearly 3 days that is the only place I can now detect a leak. My previous confusion about multiple oil leaks is I think caused by the fact that the oil actually runs inside the outer timing cover and then spreads all over the place. With the cover off it drops straight down onto the ex pipe. It such a tiny trickle I cannot believe the mess it created.
I had an enormous engine leak from the gasket behind the housing for the ignition timing thingy. That would fill up the side case and spread it's load everywhere I went. Some people may have read my story about it. Others may have seen the slick. Having fixed that, anything less seems totally oil-tight to me.
The Neill book mentions removing the ratchet nut 41340 and ratchet 41283 before removing the cover but I struggle to see how they can be seen let alone undone until the cover is off. Am I missing something here?
You're right, they can't. He's got things in the wrong order as, if you read on to the next line, he follows up by saying
Remove six screws securing end cover, take off cover and then remove ratchet and nut. The ratchet cannot be removed without taking off the cover.
That's the part where you risk disturbing the gaskets and acquire further leaks if it's stuck solid and requires a bit of tugging.
Finally (well in this post anyway), Neill also mentions removing a gear indicator bolt but my bike does not have one nor any obvious place for it to affix. The cover does have gears numbers marked though.
If you look at the end of the shaft holding the gear lever, you should see a hole in the middle. That's where the bolt fits that holds on the indicator. It's useful when you're working on the bike, as long as you've got it set in the right place, of course, but not necessary for riding.
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Ozmadman
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Re: G5 Oil Leak

Post by Ozmadman »

As far as I remember you don't need to take off the nut and ratchet at all as the cover as in my picture comes off as it is and the selector shaft with the ratchet on stays attached to the centre plate of the gearbox. Actually you don't need to remove it at all even if you strip the box down as that shaft can stay in the centre plate and unless you need to repair anything there it can stay as it is. If it does need to be dismantled then make sure the ratchet goes back on the shaft exactly as it came off in relation to the selector plate
Last edited by Ozmadman on Sun Feb 28, 2016 11:00 pm, edited 1 time in total.
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
starfield181
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Location: WILTSHIRE UK

Re: G5 Oil Leak

Post by starfield181 »

Thanks Janet & Paul. Looks like my excuses to avoid the job are not justified. I will order the bits and get stuck in - could be a while before I can report back as investigating the G5 oil leak has put me behind servicing the other bikes as well as neglecting domestic chores.

Just been told a new hall & stairs carpet is on the essential requirements list - might be able to blag some of the old bits for the garage and move up in the world!

many thanks

PeterF
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Ozmadman
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Re: G5 Oil Leak

Post by Ozmadman »

To add, paper gasket AND Wellseal I don't use Hylomar any more after I rediscovered Wellseal back from my old VW engine rebuilds days in the early 80's.. it is the best, Hylomar is too thick and liable to set in blobs and drop into areas you don't want it to.

Whatever, the manual is not totally correct and if you look at the pictures of the end cover removed you can see the selector shaft/ratchet still in position with the end cover off, you don't need to touch that nut or ratchet to do what you need to do
Last edited by Ozmadman on Mon Feb 29, 2016 7:56 am, edited 1 time in total.
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Ozmadman
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Re: G5 Oil Leak

Post by Ozmadman »

Here are two more pictures, they are of the inside of the box behind the centre plate (the part you WON'T see), they show the actual gear selector gate attached to the selector shaft. What they don't show is the other side of the plate (the part you will see when you take the outer cover off) and the ratchet and nut on the other end of that shaft (haven't got a picture of that) As you can probably see, there is no need to take that shaft assembly out of the casing at all unless the bush is badly worn and therefore no need to remove that nut an ratchet unless the ratchet needs replacing. I have rebuilt two boxes and have never had to take that shaft out of that centre plate.
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Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
starfield181
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Joined: Wed Aug 18, 2010 11:56 am
Location: WILTSHIRE UK

Re: G5 Oil Leak

Post by starfield181 »

Just getting round to ordering the seals and gaskets for my G5 gearbox. Main reason for delay was to check my friends M14 and sure enough, his was leaking from both spindles so I will order two lots of everything. What stopped me placing the order tonight was the fact that the O rings on the ratchet shaft spindle (Part # 040079) are not available. At least I have to ring or email first to make sure they are in stock.

If they prove not to be available from Jampot Spares, does anyone know what size they are as I may well already have something suitable in the workshop or can buy them elsewhere. I want to get the job done but am reluctant to start without all the necessary bits to hand.

Thanks

PeterF
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Stuoyb
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Re: G5 Oil Leak

Post by Stuoyb »

040079 is available - stock level is below the reorder safety threshold.
starfield181
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Re: G5 Oil Leak

Post by starfield181 »

There two in stock which I have ordered. I needed 4 but at least I will have some to measure up.

Peter
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Ozmadman
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Re: G5 Oil Leak

Post by Ozmadman »

starfield181 wrote:There two in stock which I have ordered. I needed 4 but at least I will have some to measure up.

Peter
Think from memory they are a 1/4" or 6mm will do it, just a guess tho
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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