General repair and servicing

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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1923richard
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Location: Hertfordshire UK

General repair and servicing

Post by 1923richard »

Hi Mn757
YES and I was very happy for your offer. I did give you an answer but in your e-mail - not here on the forum. Would you like me to give the answer here on the forum?
Maybe I have the wrong e mail address?
Richard
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1923richard
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Joined: Wed Feb 23, 2011 7:36 pm
Location: Hertfordshire UK

General repair and servicing

Post by 1923richard »

Sorry Martin. I can see now that the answer went to the webmaster. Give me your e mail and I will give you some information please.
Richard
Richard
uncle rod
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Location: MONMOUTHSHIRE UK

General repair and servicing

Post by uncle rod »

!/4 in btdc comp stroke insert flat blade screwdriver through hole of points plate and prise open the bob wieghts turn base plate till points just open. This is for 58 G2.
Regards Rod
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1923richard
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Location: Hertfordshire UK

General repair and servicing

Post by 1923richard »

Hi Uncle Rod
Thats what the instruction book said. I think thats what I have done but maybe I did wrong. I'll try again.
Thanks
Richard
wilko
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General repair and servicing

Post by wilko »

It can still be cam timing.
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Janet
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General repair and servicing

Post by Janet »

Miss, Miss! (Janet waves hand in air.)

I've thought of another possibility. A plug that sparks when out of the cylinder doesn't necessarily work when in it. Don't ask me why because I don't know.
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mn757
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Location: WEST MIDLANDS UK

General repair and servicing

Post by mn757 »

Richard,

I'll be down in Watford / Bushey in the next five weeks or so - If you haven't sorted it by then I can have a look for you.

In the meantime, so long as you have fuel reaching the plug, and a spark at the plug it must be timing, or a severe lack of compression. As Janet says, a plug can spark fine when not fitted but fail when fitted to the head. How are you checking the spark?

In terms of timing, it's been mentioned above by other people but just to re-iterate what I did;

Remove spark plug and remove the cover that allows inspection / adjustment of the pushrods. Place your finger over the plug hole and rotate the engine until you feel pressure on your finger. Bring the engine to the top of it's stroke - you should see both valvles are closed. I used a TDC tool to determine TDC. You can use anything small enough to fit in the plug hole, but don't use anything that's small enough to drop in! Get the engine to TDC. Make a mark on the tool that you have used to correspond to a fixed point on the head, e.g the plug hole. The rotate the engine backwards until the piston moves down 1/4 inch - check using your prevuious measurement. So, now your piston should be 1/4 inch before TDC on the compression stroke.

Loosen the screws that hold the points plate. Look at the small detatchable cam and see where the hightest point is, e.g the peak. You want the points to start opening just prior to this. Insert a small screwdriver into the bobweights and make sure they are fully seperated. Now rotate the plate holding the points until the points are open at the peak of the cam. Tighten the screws.

Incidentally, check the points gap.

This is what I did for my recently rebuilt engine and it started first kick.


Things that could go wrong;

I assume that the camshaft is timed correctly, e.g the small dots line up with the crank gear at the relevant place. Cant remember the details now, but it's in the manual.

Are the points opening and closing correctly?

Is the plug getting a decent spark ?

Has the fuel gone off? Doesn't take long with modern fuel.

Presume you have decent compression ?

Let us know how you get on.

uncle rod
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General repair and servicing

Post by uncle rod »

There you go, backtrack and read the last bit of whot I rit. (until points just open) Not on peak of cam. This is where the fag paper used to come in, I do it with a multi meter now I dont smoke. Havnt smoked since 1976 when I got that red flu, I still smoke in my dreams though.
Regards Rod
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1923richard
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Location: Hertfordshire UK

General repair and servicing

Post by 1923richard »

Thanks for advice again. I feel that I have tried everything and I had it almost worked out yesterday. The engine gave some explosion but out of the carburator enstead out of the exhaust every time i kicked the starter. That must be wrong. So I am continuing to work. I have used a multimeter but not I have bought a pack of cigarette paper and will try the old fasion way.
Camshaft timed correctly? I don´t see any dots??
Yes points are opening correctly!
The plug gets spark - but how can you see that when it is in?
When I take the plug out, it is a little wet - must be petrol!
The petrol is new and there is good compression.
Maybe I shoul buy a TDC tool instead of the wire I use?
Richard
wilko
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Location: victoria AUSTRALIA

General repair and servicing

Post by wilko »

Take your tappet cover off and check for pushrod movement at the right time.I.e both pushrods spinning free at top of stroke.This will give you a rough idea.
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